Service 3120728 06-14
Service and Maintenance Manual
Model
10VP
15VP
20VP
3120728
June 14 2001
ANSI
FOREWORD
The purpose of this manual is to provide users with the operating procedures essential for the promotion of
proper machine operation for its intended purpose. It is important to over-stress proper machine usage. All
information in this manual should be READ and UNDERSTOOD before any attempt is made to operate the
machine. YOUR OPERATING MANUAL IS YOUR MOST IMPORTANT TOOL - Keep it with the machine.
REMEMBER ANY EQUIPMENT IS ONLY AS SAFE AS THE OPERATOR.
BECAUSE THE MANUFACTURER HAS NO DIRECT CONTROL OVER MACHINE APPLICATION AND
OPERATION, PROPER SAFETY PRACTICES ARE THE RESPONSIBILITY OF THE USER AND HIS OPERATING PERSONNEL.
ALL INSTRUCTIONS IN THIS MANUAL ARE BASED ON THE USE OF THE MACHINE UNDER PROPER
OPERATING CONDITIONS, WITH NO DEVIATIONS FROM THE ORIGINAL DESIGN. ALTERATION AND/
OR MODIFICATION OF THE MACHINE IS STRICTLY FORBIDDEN, WITHOUT WRITTEN APPROVAL
FROM JLG INDUSTRIES, PER OSHA REGULATIONS.
THIS "SAFETY ALERT SYMBOL" IS USED TO CALL ATTENTION TO POTENTIAL HAZARDS
WHICH MAY LEAD TO SERIOUS INJURY OR DEATH IF IGNORED.
Safety of personnel and proper use of the machine are of primary concern, DANGER, WARNING, CAUTION,
IMPORTANT, INSTRUCTIONS and NOTE are inserted throughout this manual to emphasize these areas.
They are defined as follows:
DANGER INDICATES AN IMMINENTLY HAZARDOUS SITUATION WHICH, IF NOT AVOIDED WILL RESULT IN SERIOUS
INJURY OR DEATH.
WARNING INDICATES A POTENTIALLY HAZARDOUS SITUATION WHICH, IF NOT AVOIDED COULD RESULT IN SERIOUS INJURY OR DEATH.
CAUTION INDICATES A POTENTIALLY HAZARDOUS SITUATION WHICH, IF NOT AVOIDED, MAY RESULT IN MINOR OR
MODERATE INJURY. IT MAY ALSO BE USED TO ALERT
AGAINST UNSAFE PRACTICES.
IMPORTANT OR INSTRUCTIONS PROCEDURES ESSENTIAL
FOR SAFE OPERATION AND WHICH, IF NOT FOLLOWED
MAY RESULT IN A MALFUNCTION OR DAMAGE TO THE
MACHINE.
Also in this Manual "Notes:" are used to provide information of special interest.
JLG INDUSTRIES, INC. MAY HAVE ISSUED SAFETY RELATED BULLETINS FOR YOUR JLG PRODUCT. CONTACT JLG INDUSTRIES, INC. OR THE LOCAL AUTHORIZED JLG DISTRIBUTOR FOR INFORMATION CONCERNING SAFETY RELATED BULLETINS WHICH MAY HAVE BEEN ISSUED FOR YOUR JLG PRODUCT. ALL ITEMS REQUIRED BY THE SAFETY RELATED
BULLETINS MUST BE COMPLETED ON THE AFFECTED JLG PRODUCT.
Due to the continuous product improvements, JLG Industries, Inc. reserves the right to make specification changes without
prior notification. Contact JLG Industries, Inc. for updated information.
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INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS
INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS
A. GENERAL
C. MAINTENANCE
This section contains the general safety precautions
which must be observed during maintenance of the aerial
platform. It is of utmost importance that maintenance personnel pay strict attention to these warnings and precautions to avoid possible injury to themselves or others or
damage to the equipment. A maintenance program must
be established by a qualified person and must be followed
to ensure that the machine is safe to operate.
MODIFICATION OF THE MACHINE WITHOUT CERTIFICATION BY
A RESPONSIBLE AUTHORITY THAT THE MACHINE IS AT LEAST
AS SAFE AS ORIGINALLY MANUFACTURED IS A SAFETY VIOLATION.
The specific precautions to be observed during machine
maintenance are inserted at the appropriate point in the
manual. These precautions are, for the most part, those
that apply when servicing hydraulic and larger machine
component parts.
Your safety, and that of others, is the first consideration
when engaging in the maintenance of equipment. Always
be conscious of component weight and never attempt to
move heavy parts without the aid of a mechanical device.
Do not allow heavy objects to rest in an unstable position.
When raising a portion of the equipment, ensure that adequate support is provided.
FAILURE TO COMPLY WITH SAFETY PRECAUTIONS LISTED IN
THIS SECTION COULD RESULT IN MACHINE DAMAGE, PERSONNEL INJURY OR DEATH AND IS A SAFETY VIOLATION.
• REMOVE ALL RINGS, WATCHES, AND JEWELRY
WHEN PERFORMING ANY MAINTENANCE.
• DO NOT WEAR LONG HAIR UNRESTRAINED, OR
LOOSE FITTING CLOTHING AND NECKTIES WHICH
ARE APT TO BECOME CAUGHT ON OR ENTANGLED
IN EQUIPMENT.
• OBSERVE AND OBEY ALL DANGER, WARNING, CAUTION AND OTHER INSTRUCTIONS ON MACHINE
AND IN SERVICE MANUAL.
• KEEP STANDING SURFACES AND HAND HOLDS
FREE OF OIL, GREASE, WATER, ETC.
• NEVER WORK UNDER AN ELEVATED PLATFORM
UNTIL PLATFORM HAS BEEN SAFELY RESTRAINED
FROM ANY MOVEMENT BY BLOCKING OR OVERHEAD SLING.
• BEFORE MAKING ADJUSTMENTS, LUBRICATING OR
PERFORMING ANY OTHER MAINTENANCE, SHUT
OFF ALL POWER CONTROLS.
• BATTERY SHOULD ALWAYS BE DISCONNECTED
DURING REPLACEMENT OF ELECTRICAL COMPONENTS.
• KEEP ALL SUPPORT EQUIPMENT AND ATTACHMENTS STOWED IN THEIR PROPER PLACE.
SINCE THE MACHINE MANUFACTURER HAS NO DIRECT CONTROL OVER THE FIELD INSPECTION AND MAINTENANCE,
SAFETY IN THIS AREA IS THE RESPONSIBILITY OF THE OWNER/
OPERATOR.
• USE ONLY APPROVED, NONFLAMMABLE CLEANING
SOLVENTS.
B. HYDRAULIC SYSTEM SAFETY
1. It should be particularly noted that the machines
hydraulic systems operate at extremely high and
potentially dangerous pressures. Every effort should
be made to relieve any system pressure prior to disconnecting or removing any portion of the system.
2. Relieve system pressure by activating the lift DOWN
control with the platform completely lowered to
direct any line pressure back into the return line to
the reservoir. Pressure feed lines to system components can then be disconnected with minimal fluid
loss.
3120728
– JLG Lift –
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INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS
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b
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3120728
EFFECTIVITY PAGE
EFFECTIVITY CHANGES
September 15, 1997 – Original Issue of Manual
January 10, 1998 – Change 1– Pages Affected:
Revision Log - Page c
Table of Contents - Page ii
Section 3 - Pages 3-8 & 3-9
February 7, 2000 – Revised – Pages Affected: Section-1, Page 1-5, Table 1-5.
Section-2, Page 2-18, Table 2-3.
(removed lube check requirement for drive wheel gear box)
March 22, 2000–
Revised – Added 20VP UL-EE Option.
September 8, 2000 – Revised Complete Manual
October 19, 2000 – Revised – Pages Affected:Section-2, Pages 2-20 thru 2-22 also 2-32 and 2-33.
Section-3, Page 3-16, added Table 3-3.
November 15, 2000 – Revised – Pages Affected:Section-1, Page 1-1
Section-2, Pages 2-33 & 2-34.
June 14, 2001 – Revised – Pages Affected:Section-2, Pages 2-23 thru 2-25
3120728
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EFFECTIVITY PAGE
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d
– JLG Lift –
3120728
TABLE OF CONTENTS
SUBJECT - SECTION, PARAGRAPH
PAGE NO.
SECTION INTRODUCTION - - MAINTENANCE SAFETY PRECAUTIONS
A
B
C
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .a
Hydraulic System Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .a
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .a
Effectivity Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .c
SECTION 1 - SPECIFICATIONS
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Component Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Performance Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Torque Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Lubrication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Hydraulic Pressure Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Cylinder Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Serial Number Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
SECTION 2 - SERVICE PROCEDURES
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
2.10
2.11
2.12
2.13
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Servicing And Maintenance Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Lubrication Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
Positioning Lift For Access To Components Located Under The Base Frame . . . . . . . . . . . . . . .2-4
Drive Motor Component Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Platform Control Box Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-15
Battery Charger Assembly And Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-20
Hydraulic Lift Cylinder - Removal, Inspection And Rebuild . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-23
Mast Assembly And Disassembly Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-26
Mast To Base Frame Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-35
Mast Chains/cables And Sequencing Cables Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-36
Sequence Cable Replacement Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-38
Preventive Maintenance And Inspection Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-40
SECTION 3 - TROUBLESHOOTING
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
3.10
3.11
3120728
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Troubleshooting Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Hydraulic Circuit Checks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Electrical Circuit Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Troubleshooting Section - Table Of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-15
Ohm Ratings For Various Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-16
Main Power Circuit Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-17
Drive Train Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-20
Mast Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-30
Hydraulic Leak Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-41
Base Frame Components Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-42
– JLG Lift –
i
TABLE OF CONTENTS
LIST OF FIGURES
FIGURE NO.
1-1.
1-2.
1-3.
1-4.
2-1.
2-2.
2-3.
2-4.
2-5.
2-6.
2-7.
2-8.
2-9.
2-10.
2-11.
2-12.
2-13.
2-14.
2-15.
2-16.
2-17.
2-18.
2-19.
2-20.
2-21.
2-22.
3-1.
3-2.
3-3.
3-4.
3-5.
3-6.
TITLE
PAGE NO.
Hydraulic Pressure Setting - Adjustment Screw Located at Base of Pump Motor . . . . . . . . . . . .1-3
Hydraulic Pressure Gauge Installation.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Torque Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Lubrication Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Accessing Machine Underside Components by Lifting with a Fork Truck. . . . . . . . . . . . . . . . . . .2-4
Check Torque Limit Clutch - Torque Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Torque Limit Clutch - Adjustment Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
Brake Assembly Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
Brake Armature Plate & Brake Disk Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
Manual Release Brake Cable Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Drive Motor Assembly Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9
Drive Motor Gear Box Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10
Gear/Pinion Shaft Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-11
Drive Shaft Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12
Drive Motor Brush Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-13
Drive Motor Brush Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-13
Correct/Incorrect Brush Spring Bracket Positions.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-14
Platform Control Box Assembly (Exploded View). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-15
Platform Control - Circuit Board Component Wiring Connections. . . . . . . . . . . . . . . . . . . . . . . . .2-17
Machine Positioned for Cylinder Removal.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-23
Lift Cylinder Internal Component Assembly Cross-Section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-25
Mast Section - Assembly Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-26
10VP Mast Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-28
15VP Mast Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-29
20VP Mast Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-30
Mast Chain/Cable/Sequence Cable Adjustment Components. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-37
LED Battery/Fault Code Indicator Strip on Platform Controller Box. . . . . . . . . . . . . . . . . . . . . . . .3-2
Overview of Standard Electrical System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6
VP Electrical Diagram. (VP Series - Standard) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-8
Overview of VP UL-EE Approved Optional Electrical System. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10
VP Electrical Diagram. (with UL-EE Approved Option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-12
Hydraulic Diagram. (VP Series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-14
LIST OF TABLES
TABLE NO.
1-1.
1-2.
1-3.
1-4
1-5.
1-6
2-1
2-2
2-3
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
ii
TITLE
PAGE NO.
Machine GVW and Wheel Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Hydraulic Oil Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Lubrication Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Machine Interlock Switch Operating Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Cylinder Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Lubrication Intervals for Various Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Chain Stretch Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
VP Series Mast Component Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-26
Preventive Maintenance & Inspection Schedule. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-41
MC-1 WARNING CODES (Indicated by 3 beeps, then slow flashing LED’s). . . . . . . . . . . . . . . . .3-3
MC-1 ERROR CODES (Indicated by rapid LED flashing and periodic beep) . . . . . . . . . . . . . . . .3-4
Ohm Ratings for Various Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-16
Unit will not Power Up From Ground Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-17
No Power At Platform Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-18
Won’t Drive. (Platform Lowered or Elevated) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-20
Elevation Switch Circuit Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-20
Brake Limit Switch Circuit Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-21
– JLG Lift –
3120728
TABLE OF CONTENTS
3-9
3-10
3-11
3-12
3-13
3-14
3-15
3-16
3-17
3-18
3-19
3-20
3-21
3-22
3-23
3-24
3-25
3-26
3-27
3-28
3-29
3-30
3-31
3-32
3-33
3120728
Drive Motor/Circuit Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-21
Brake Switch/Circuit Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-21
Won’t Drive with Platform Elevated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-22
Tilt Sensor Circuit Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-22
PHP Limit Switch Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-23
Won’t Climb Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-24
Drives In Opposite Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-25
Only Drives A Short Distance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-26
E-Stop and Key Switch Circuit Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-27
Won’t Drive Straight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-28
Noise from Drive Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-29
Platform Will Not Lift Up Using Platform Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-30
Pump Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-31
Pump Valves Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-32
Platform Will Not Lower Using Platform Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-33
Unit Will Not Lift Up From Ground Control Toggle Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-34
Unit Will Not Lower From Ground Control Toggle Switch.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-35
Platform Will Not Lower Manually. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-36
Platform Lift Up and Down Jerky. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-37
Mast Noisy when Lifting and Lowering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-38
Platform (Mast) Won’t Stay Elevated. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-39
Platform (Mast) Descends Too Slowly.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-40
Hydraulic Leak Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-41
Caster Wheels Not Operating Freely. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-42
Pot Hole Protection (PHP) Bars Will Not Set. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-42
– JLG Lift –
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TABLE OF CONTENTS
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iv
– JLG Lift –
3120728
SECTION 1 - SPECIFICATIONS
SECTION 1. SPECIFICATIONS
1.1
Batteries/Battery Charger
CAPACITIES
Batteries (2) – 12 Volt / 80 Amp Hour –
System Voltage
Deep CycleMarine - RV
All VP Models –24 Volt DC (2 - 12 volt DC batteries)
Battery Charger –
U.S.A./CAN. –120 Volt A.C. / 60 Hz input
Hydraulic Oil Reservoir
Brazil - 220 Volt A.C./ 60 Hz input
All VP Models – 5 qts. U.S. (4.7 ltr.)
24 volt, 10 amp output with 2 amp finish
1.2
Reset Circuit Breaker
COMPONENT DATA
Automatic Charge Circuit
Hydraulic Pump/Pump Motor Assembly
Plug Interlock Circuit
Pump Motor - 24 Volt DC motor
Pump Displacement –
1.3
10 & 15VP – .098 cu. in./rev. (1.6cc/rev.)
PERFORMANCE DATA
Platform Capacity(All Platforms except
Extendible)
20VP – .049 cu. in./rev. (0.8cc/rev )
Pump Output (Max.) –
10 & 15VP - 1.20 gpm @ 2200 psi
10VP –350 lbs. (160 kg)
20VP – 0.65 gpm @ 2200 psi
15VP –350 lbs. (160 kg)
Hydraulic System Pressure Setting –
20VP –350 lbs. (160 kg)
10 & 15VP - 1000 psi (68.95 bar)
Extendible Platform Capacity
20VP - 2500 psi (172.3 bar)
ANSI (U.S.) – 300 lbs. (136 kg)
Rear Wheel Drive Motors
CSA (CAN.) – 250 lbs. (114 kg)
DriveMotors -
Platform Size
24 Volt DC w/perm. magnet
Standard Platform – 26 in. x 26 in.
(66cm) x (66cm)
Right angle gear
Maintenance free sealed gear
Brake shaft and drive shaft,Integral to Motor
Machine Height (In Stowed Position)
Parking Brake (must be released for pushing)
VP Series - 79 in. (201cm) height
Table 1-1.
Machine GVW and Wheel Loads
VP MODEL
CONFIG.
GVW (no load)
DRIVE WHEEL
(ea) w/rated load
CASTER
(ea) w/rated load
PSI
(Drive)
PSI
(Caster)
10VP
ANSI (U.S.)
930 lb. (422 kg)
424 lb.
216 lb.
76 psi
102 psi
CSA (CAN.)
930 lb. (422 kg)
424 lb.
216 lb.
76 psi
102 psi
ANSI (U.S.)
1,355 lb. (615 kg)
604 lb.
249 lb.
108 psi
117 psi
CSA (CAN.)
1,425 lb. (647 kg)
630 lb.
257 lb.
113 psi
121 psi
ANSI (U.S.)
1,910 lb. (867 kg)
750 lb.
400 lb.
134 psi
188 psi
CSA (CAN.)
2,100 lb. (953 kg)
774 lb.
470 lb.
140 psi
220 psi
15VP
20VP
3120728
– JLG Lift –
1-1
SECTION 1 - SPECIFICATIONS
Base Footprint
1.5
VP Series - 32 in. (81cm) width 56 in. (1.42m) length
LUBRICATION
Hydraulic Oil
Max. Platform Height (mast extended)
Hydraulic oils must have anti-wear qualities at least to API
Service Classification GL-3, and sufficient chemical stability for mobile hydraulic system service. JLG Industries,
recommends Mobilfluid 424 hydraulic oil, which has an
SAE viscosity of 10W-30 and a viscosity index of 152.
10VP – 10 ft. 6 in.(3.2m)
15VP – 15 ft.(4.5m)
20VP – 19 ft. 9 in.(5.9m)
For cold weather applications, i.e. when temperatures
remain consistently below +20°F (–7°C) JLG recommends using Mobil DTE 13 hydraulic oil.
Platform Working Height (average)
10VP –16 ft. 6 in.(4.8m)
Aside from JLG recommendations, it is not advisable to
mix oils of different brands or types, as they may not contain the same required additives or be of comparable viscosities. If use of hydraulic oil other than Mobilfluid 424 is
desired, contact JLG Industries for proper recommendations.
15VP –21 ft.(6.4m)
20VP –25 ft. 9 in.(7.6m)
Machine Drive Speed (max.)*
Platform Lowered - 2 mph (3.22 kph)
Platform Elevated - 0.5 mph (.81 kph)
Table 1-2. Hydraulic Oil Operating Range
(reduced by limit switch)
* Variable to maximum with speed cut back.
HYDRAULIC SYSTEM OPERATING
TEMPERATURE RANGE
SAE VISCOSITY
GRADE
0° F to +23° F
(-18° C to -5° C)
10W
0° F to +210° F
(-18° C to +99° C)
10W-20, 10W-30
50° F to 210° F
(+10° C to +210° C)
20W-20
Amperage Draw (average)
Lift - 12 amps.Drive - 20 amps.
Interlock Switch Operating Conditions
Table 1-4. shown, lists machine response to various interlock switch positions.
Lubrication Specifications
1.4
TORQUE REQUIREMENTS
Table 1-3. Lubrication Specifications
When maintenance becomes necessary or a fastener has
loosened, refer to the Torque Chart, Figure 1-3., Torque
Chart. to determine proper torque value.
KEY
SPECIFICATIONS
MPG -
Multipurpose Grease having a minimum dripping point
of 350° F. Excellent water resistance and adhesive qualities, and being of extreme pressure type. (Timken OK
40 pounds minimum.)
EPGL -
Extreme Pressure Gear Lube (oil) meeting API service
classification GL-5 or MIL-Spec MIL-L-2105.
HO
Hydraulic Oil. ISO-Vg grade 32, 46.
-
Table 1-4. Machine Interlock Switch Operating Conditions.
Mast Elevation
mast retracted
mast retracted
mast extended
mast extended
mast extended
mast retracted
mast retracted
1-2
Drive Cutout
(PHP System)
bars raised
bars raised
bars lowered
bars raised (blocked)
bars lowered
bars raised
bars raised/battery charger
plugged-in
Tilt Status
Brake Status
(not tilted)
(not tilted)
(not tilted)
(not tilted)
(tilt)
(tilt)
engaged
disengaged
engaged
engaged
engaged
engaged
(not tilted)
engaged
– JLG Lift –
Controller Response
Full Drive and Lift
Drive and Lift Disabled
Drive 25% maximum
Drive Disabled
Drive and Lift disabled
Lift Disabled
Drive Disabled
3120728
SECTION 1 - SPECIFICATIONS
1.6
HYDRAULIC PRESSURE ADJUSTMENT
Adjust system pressure so that platform will raise with
rated capacity in platform.
The following are recommended factory pressure settings;
VP10,VP15 –1000 psi
VP20 – 2500 psi
Turning adjustment screw clockwise increases system
pressure, turning screw counterclockwise decreases
system pressure.
RETURN
LINE
REPLACE ELBOW
WITH A T-FITTING
TO CONNECT
PRESSURE GAUGE
HERE
EXTEND
LINE
PRESSURE
GAUGE
Make pressure adjustment with oil at normal operating
temperature. If pressure is set when oil is cold, platform
may not raise rated load after oil has warmed.
PRESSURE
ADJUSTMENT
SCREW
Figure 1-2. Hydraulic Pressure Gauge Installation.
1.7
ADJUSTMENT
SCREW CAP
CYLINDER SPECIFICATIONS
NOTE: All dimensions are given in inches (in), with the metric equivalent, centimeters (cm), given in parentheses.
Table 1-5. Cylinder Specifications
BORE
in./(cm)
STROKE
in./(cm)
ROD DIA.
in./(cm)
Lift Cylinder 10VP
1.50
(3.81)
54.50
(138.43)
1.125
(2.86)
Lift Cylinder 15VP
1.50
(3.81)
54.50
(138.43)
1.125
(2.86)
Lift Cylinder 20VP
1.50
(3.81)
54.50
(138.43)
1.125
(2.86)
DESCRIPTION
Figure 1-1. Hydraulic Pressure Setting - Adjustment
Screw Located at Base of Pump Motor
(Remove Hex Head Cap as Shown)
ONLY OPEN HYDRAULIC SYSTEM LINES WITH THE MAST LOWERED TO RELIEVE PRESSURE IN THE SYSTEM. CAREFULLY
LOOSEN REQUIRED FITTINGS, WEAR SAFETY PROTECTION
EQUIPMENT WHEN WORKING WITH HYDRAULIC SYSTEMS.
Connect pressure gauge as shown in Figure 1-2., Hydraulic Pressure Gauge Installation.
Select a T-Fitting to exactly match the thread size of the
pump (.562 x 18 THD), pressure line (.562 x 18 THD) and
gauge fitting as required.
3120728
1.8
SERIAL NUMBER LOCATION
For machine identification, a serial number plate is affixed
to the machine. The plate is located on the back of the
mast, just above the mast support bracket.
– JLG Lift –
1-3
SECTION 1 - SPECIFICATIONS
Figure 1-3. Torque Chart.
1-4
– JLG Lift –
3120728
SECTION 1 - SPECIFICATIONS
6
1
2
3
4, 5
Figure 1-4. Lubrication Chart.
Table 1-6.Lubrication Intervals for Various Components
INTERVAL HOURS
ITEM
COMPONTENT
NO/TYPE
LUBE POINTS
LUBE/METHOD
3
6
MONTHS MONTHS
150 Hrs. 300 Hrs.
1
Hydraulic Oil
Fill To Line on
Reservoir
5 Qt. Reservoir
2
Drive Wheel
Bearings
4 - Grease Fittings MPG- Pressure Gun
3
Drive Wheel
Gear Box
2 - Gear Box
Gear Oil
4
Caster Axles
2 - Grease Fitting
MPG - Pressure Gun
5
Swivel Raceways 2 - Front Casters
MPG - Pressure Gun
✔
✔
6
Mast Chains *
Chain Lube - Brush or
Spray
✔
2 - Per Section
1
2
YEAR
YEARS
600 Hrs. 1200 Hrs.
HO - Check Hyd. Oil
Level
HO - Change Hyd. Oil
✔
COMMENTS
Check Hydraulic Oil every 10 hrs.
Change Hydraulic Oil every 1200
hrs.
✔
Change only when serviced
requires 6 oz. (175 cc’s) to fill.
Inspect, lubricate if dry or rusting.
* Applies Only to Mast Sections with Chains.
Key to Lubricants: MPG - Multipurpose Grease
HO - Hydraulic Oil - See Section 1.5, "Lubrication" in Service Manual.
GEAR OIL - Good Quality Worm Gear Oil - SAE 90 - AGMA#5 - EP Compounded
Notes: 1. Be certain to lubricate like items on each side of the machine.
2. Recommended lubricating intervals are based on normal use. If machine is subjected to severe operating conditions,
such as a high number of cycles, location, corrosive/dirty environment, etc., user must adjust lubricating requirements accordingly.
3. Prior to checking hydraulic oil level, operate machine through one complete cycle of lift function (full up and down). Failure to do so will
result in incorrect oil level reading on the hydraulic reservoir.
3120728
– JLG Lift –
1-5
SECTION 1 - SPECIFICATIONS
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1-6
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
SECTION 2. SERVICE PROCEDURES
2.1
GENERAL
This section provides general information to assist in the
performance of maintenance on the personnel lift.
Descriptions, techniques and specific procedures are
designed to provide the safest and most efficient maintenance for use by personnel responsible for ensuring the
correct installation and operation of machine components
and systems.
selves. As soon as a line or component is disconnected,
cap or cover all openings to prevent entry of foreign matter.
Clean and inspect all parts during servicing or maintenance, and assure that all passages and openings are
unobstructed. Cover all parts to keep them clean. Be sure
all parts are clean before they are installed. New parts
should remain in their containers until they are ready to be
used.
Components Removal and Installation
WHEN AN ABNORMAL CONDITION IS NOTED AND PROCEDURES
CONTAINED HEREIN DO NOT SPECIFICALLY RELATE TO THE
NOTED IRREGULARITY, WORK SHOULD BE STOPPED AND
TECHNICALLY QUALIFIED GUIDANCE OBTAINED BEFORE WORK
IS RESUMED.
2.2
SERVICING AND MAINTENANCE
GUIDELINES
General
The following information is provided to assist you in the
use and application of servicing and maintenance procedures contained in this chapter.
Safety and Workmanship
Your safety, and that of others, is the first consideration
when engaging in the maintenance of equipment. Always
be conscious of component weight. Never attempt to
move heavy parts without the aid of a mechanical device.
Do not allow heavy objects to rest in an unstable position.
When raising a portion of the equipment, ensure that adequate support is provided.
NEVER WORK UNDER AN ELEVATED PLATFORM UNTIL PLATFORM HAS BEEN SAFELY RESTRAINED FROM ANY MOVEMENT
BY BLOCKING OR OVERHEAD SLING.
Cleanliness
The most important single item in preserving the long service life of a machine is to keep dirt and foreign materials
out of the vital components. Precautions have been taken
to safeguard against this. Shields, covers, seals, and filters are provided to keep the wheel bearings, mast sections and oil supply clean; however, these items must be
maintained on a scheduled basis in order to function
properly.
At any time when oil lines are disconnected, clear adjacent areas as well as the openings and fittings them-
3120728
Use adjustable lifting devices, whenever possible, if
mechanical assistance is required. All slings (chains,
cables, etc.) should be parallel to each other and as near
perpendicular as possible to top of part being lifted.
Should it be necessary to remove a component on an
angle, keep in mind that the capacity of an eyebolt or similar bracket lessens, as the angle between the supporting
structure and the component becomes less than 90
degrees.
If a part resists removal, check to see whether all nuts,
bolts, cables, brackets, wiring, etc., have been removed
and that no adjacent parts are interfering.
Component Disassembly and Reassembly
When disassembling or reassembling a component, complete the procedural steps in sequence. Do not partially
disassemble or assemble one part, then start on another.
Always recheck your work to assure that nothing has been
overlooked. Do not make any adjustments, other than
those recommended, without obtaining proper approval.
Pressure-Fit Parts
When assembling pressure-fit parts, use an “anti-seize” or
molybdenum disulfide base compound to lubricate the
mating surface.
Bearings
When a bearing is removed, cover it to keep out dirt and
abrasives. Clean bearings in nonflammable cleaning solvent and allow to drip dry. Compressed air can be used
but do not spin the bearing.
Discard bearings if the races and balls (or rollers) are pitted, scored, or burned.
If bearing is found to be serviceable, apply a light coat of
oil and wrap it in clean (waxed) paper. Do not unwrap
reusable or new bearings until they are ready to install.
Lubricate new or used serviceable bearings before installation. When pressing a bearing into a retainer or bore,
– JLG Lift –
2-1
SECTION 2 - SERVICE PROCEDURES
apply pressure to the outer race. If the bearing is to be
installed on a shaft, apply pressure to the inner race.
Gaskets
Check that holes in gaskets align with openings in the
mating parts. If it becomes necessary to hand-fabricate a
gasket, use gasket material or stock of equivalent material
and thickness. Be sure to cut holes in the right location, as
blank gaskets can cause serious system damage.
Bolt Usage and Torque Application
Use bolts of proper length. A bolt which is too long will
bottom before the head is tight against its related part. If a
bolt is too short, there will not be enough thread area to
engage and hold the part properly. When replacing bolts,
use only those having the same specifications of the original, or one which is equivalent.
Unless specific torque requirements are given within the
text, standard torque values should be used on heattreated bolts, studs, and steel nuts, in accordance with
recommended shop practices. (See Figure 1-1.)
Hydraulic Lines and Electrical Wiring
Clearly mark or tag hydraulic lines and electrical wiring, as
well as their receptacles, when disconnecting or removing
them from the unit. This will assure that they are correctly
reinstalled.
Hydraulic System
Keep the system clean. If evidence of metal or rubber particles is found in the hydraulic system, drain and flush the
entire system.
Disassemble and reassemble parts on clean work surface. Clean all metal parts with non-flammable cleaning
solvent. Lubricate components, as required, to aid assembly.
Mast Chain Inspection Procedure
MAST CHAINS TO BE INSPECTED AND LUBRICATED EVERY
THREE MONTHS.
Inspect mast chains for the following conditions:
Wear: Always inspect that segment of chain that operates
over a sheave. As the chain flexes over the sheaves, joints
and plate edges very gradually wear. Chain “stretch” can
be measured using a manufacturers wear scale or steel
tape. When chains have elongated 3% they must be
removed and replaced. Refer to Table 2-1 for proper chain
specifications and allowable stretch tolerances. Peening
and wear of chain plate edges are caused by sliding over
a chain worn contact face of a sheave, or unusually heavy
loads. All of the above require replacement of the chain
and correction of the cause. Chain side wear, noticeable
when pin heads and outside plates show a definite wear
pattern, is caused by misalignment of the sheave/chain
anchors and must be corrected promptly. Do not repair
chains; if a section of chain is damaged, replace the entire
chain set.
Rust and Corrosion: Rust and corrosion will cause a
major reduction in the load carrying capacity of the chain,
because these are primary reasons for side plate cracking. The initial lubrication at the factory is applied in a hot
dip tank to assure full penetration into the joint. Do not
steam clean or degrease chains. At time of chain installation, factory lube must be supplemented by a maintenance program to provide a film of oil on the chains at all
times. If chains are corroded, they must be inspected,
especially the outside plates, for cracks in-line with the
pins. If cracks are found, replace the chain; if no cracks
are discovered, lubricate the chains by dipping in heated
oil, and reinstall on the machine. Keep chains lubricated.
Table 2-1. Chain Stretch Tolerance
Lubrication and Servicing
Components and assemblies requiring lubrication and
servicing are shown in the Lubrication Chart, (See Figure
1-2.). Service applicable components with the amount,
type, and grade of lubricant recommended in this manual,
at the specified intervals. When recommended lubricants
are not available, consult your local supplier for an equivalent that meets or exceeds the specifications listed.
Batteries
Clean batteries, using a non-metallic brush and a solution
of baking soda and water. Rinse with clean water. After
cleaning, thoroughly dry batteries and coat terminals with
an anti-corrosion compound.
2-2
Chain Size
Pin to Pin
Measurement
Allowable Stretch
.50" pitch
12" or 24 pitches
.24 in./12 in. span
.625 pitch
15" or 24 pitches
.30 in./15 in. span
Fatigue Cracks: Fatigue is a phenomenon that affects
most metals, and is the most common cause of chain
plate failures. Fatigue cracks are found through the link
holes, perpendicular (90 degrees) from the pin in-line
position. Inspect chains carefully after long time use and
heavy loading for this type of crack. If any cracks are discovered, replace all chains, as seemingly sound plates
are on the verge of cracking. Fatigue and ultimate
strength failures on JLG Lifts are incurred as a result of
severe abuse as design specs are well within the rated lifting capacity of these chains.
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Tight Joints: All joints in the leaf chain should flex freely.
On leaf chain, tight joints are usually caused by rust/corrosion, or the inside plates “walking” off the bushing. Limber
up rusty/corroded chains (after inspecting care fully) with
a heavy application of oil (preferably a hot oil dip). Tap
inside “walking” plates inward; if “walking” persists,
replace the chain. This type of problem is accelerated by
poor lubrication maintenance practice, and most tight
joint chains have been operated with little or no lubrication. Tight joints on leaf chain are generally caused by:
a. Bent pins or plates.
Inspection should be more frequent as cables approach
the end of their useful lives.
Only the surface wires of the cable require inspection, do
not attempt to open the cable. Any deterioration resulting
in any loss of original strength, such as described below,
shall be noted, and then a determination made if further
use would constitute a hazard.
Mast cables must be replaced after machine has been in
service for five (5) years, regardless of cable condition, or
sooner if conditions dictate.
Conditions such as the following shall be sufficient reason
for questioning continual use of the [cable] or increasing
the frequency of inspection:
b. Rusty joints.
c. Peened plate edges.
Oil rusty chains, and replace chains with bent or peened
chain components. Keep chains lubricated.
1. In running ropes, six randomly distributed broken
wires in one lay or three broken wires in one strand
in one lay.
Protruding or Turned Pins: Chains operating with inadequate lube generate tremendous friction between the pin
and plates (pin and bushing on leaf chain). In extreme
cases, this frictional torque can actually turn the pins in
the outside press-fit plates. Inspect for turned pins, which
can be easily spotted as the “V” flats on the pin heads are
no longer in line. Replace all chains showing evidence of
turned or protruding pins. Keep chains lubricated.
2. One outer wire broken at the point of contact with
the core of the rope which has worked its way out of
the rope structure and protrudes or loops out from
the rope structure. Additional inspection of this section is required.
3. Wear of one-third the original diameter of outside
individual wires.
Chain Anchors and Sheaves: An inspection of the chain
must include a close examination of chain anchors and
sheaves. Check chain anchors for wear breakage and
misalignment. Anchors with worn or broken fingers should
be replaced. They should also be adjusted to eliminate
twisting the chain for an even load distribution.
Inspect the sheaves, sheave bearings, sheave grooves
and pins for extreme wear, replace as necessary. A worn
sheave can mean several problems, as follows:
a. Chains too tight.
b. Sheave bearings/pin bad.
c. Bent/misaligned chains.
4. Kinking, crushing, birdcaging or any other damage
resulting in distortion of the rope structure.
5. Evidence of any heat damage from any cause.
6. Reductions from nominal diameter of more than;
a. 1/64th in. (0.4mm) for diameters up to and
including 5/16th in. (8mm);
NOTE: A good indicator of a stretched extend/retract cable
is if the adjusting nuts are bottomed out. If no adjustment remains the cables have stretched and need
replacement.
Also check for cracked, bent, worn, severely corroded, or
improperly installed cable ends.
Mast Cable Inspection Procedure
Inspect sheaves, sheave grooves, and sheave pins for
excessive wear, replace as necessary.
MAST CABLES ARE TO BE INSPECTED EVERY THREE MONTHS
OR MORE FREQUENTLY AS DESCRIBED FOLLOWING.
2.3
LUBRICATION INFORMATION
Hydraulic System
WEAR PROTECTIVE GLOVES TO PROTECT HANDS WHEN HANDLING CABLE.
The periodic inspection shall cover the entire length of the
cable. The inspection frequency shall be based on such
factors as expected cable life as determined by experience on the particular application or similar installations,
severity of environment, percentage of capacity lifts, frequency rates of operation, and exposure to shock loads.
3120728
The primary enemy of a hydraulic system is contamination. Contaminants enter the system by various means,
e.g., using inadequate hydraulic oil, allowing moisture,
grease, filings, sealing components, sand, etc., to enter
when performing maintenance, or by permitting the pump
to cavitate due to insufficient system warm-up or leaks in
the pump supply.
The design and manufacturing tolerances of the component working parts are very close, therefore, even the
smallest amount of dirt or foreign matter entering a system
– JLG Lift –
2-3
SECTION 2 - SERVICE PROCEDURES
can cause wear or damage to the components and generally results in faulty operation. Every precaution must be
taken to keep hydraulic oil clean, including reserve oil in
storage.
2.4
POSITIONING LIFT FOR ACCESS TO
COMPONENTS LOCATED UNDER THE
BASE FRAME
Cloudy oils indicate a high moisture content which permits organic growth, resulting in oxidation or corrosion. If
this condition occurs, the system must be drained,
flushed, and refilled with clean oil.
Access to the underside of the VP lift can be obtained by
lifting the machine with a fork lift truck, using the fork lift
pockets in the base frame.
It is not advisable to mix oils of different brands or types,
as they may not contain the same required additives or be
of comparable viscosities. Good grade mineral oils, with
viscosities suited to the ambient temperatures in which
the machine is operating, are recommended for use.
Lifting with a Fork Truck (See Figure 2-1.)
NOTE: Metal particles may appear in the oil of new
machines due to the wear-in of meshing components.
Hydraulic Oil
1. Choose a fork lift truck capable of safely handling
the full weight of the machine.
2. Locate work area on a firm, level surface.
KEEP MACHINE LEVEL OR SLIGHTLY TILTED TOWARD FORKLIFT
TRUCK WHEN LIFTING TO PREVENT MACHINE FROM SLIDING
OFF LIFTING TINES.
For best performance, JLG recommends the use of ISOVg grade 32, 46 oil with a viscosity range between 15-250
SUS at 100 degrees F (32-54 cST at 40 degrees C). Refer
to Section 1-5 of this Service Manual for recommended
hydraulic oils.
Changing Hydraulic Oil
Use of any of the recommended hydraulic oils eliminates
the need for changing the oil on a regular basis. If it is necessary to change the oil, use only those oils meeting or
exceeding the specifications appearing in this manual. If
unable to obtain the same type of oil supplied with the
machine, consult local supplier for assistance in selecting
the proper equivalent. Avoid mixing petroleum and synthetic base oils. JLG Industries recommends changing the
hydraulic oil annually.
3. When lifting with a fork truck, lift only using the fork
lift-truck pockets running the length of the machine’s
base frame from rear to front.
4. After lifting machine to desired work height, place
support stands under the machine. The support
stands must reach from the floor to the bottom of the
machine and be capable of safely handling the
weight of the machine.
Use every precaution to keep the hydraulic oil clean. If the
oil must be poured from the original container into
another, be sure to clean all possible contaminants from
the service container.
While the unit is shut down, a good preventive maintenance measure is to make a thorough inspection of all
hydraulic components, lines, fittings, etc., as well as a
functional check of each system, before placing the
machine back in service.
Lubrication Specifications
Specified lubricants, as recommended by the component
manufacturers, are always the best choice, however,
multi-purpose greases usually have the qualities which
meet a variety of single purpose grease requirements.
Should any question arise regarding the use of greases in
maintenance stock, consult your local supplier for evaluation. Refer to Table 1-3 in this Service Manual for an explanation of the lubricant key designations appearing in the
Lubrication Chart.
2-4
– JLG Lift –
LIFT USING ONLY THE
FORK LIFT POCKETS
RUNNING THE LENGTH
OF THE BASE FRAME
PLACE
SUPPORT
STAND
BETWEEN
MACHINE
AND
FLOOR
Figure 2-1. Accessing Machine Underside
Components by Lifting with a Fork Truck.
3120728
SECTION 2 - SERVICE PROCEDURES
2.5
DRIVE MOTOR COMPONENT SERVICE
PROCEDURES
Torque Limiting Clutch Maintenance
Checking Clutch - Torque Setting (ft. lb.)
NOTE: Check that the machines brakes are engaged before
applying torque to the rear drive wheels.
1. Remove the drive wheels from the drive axles.
VP Series machines are equipped with a torque limiting
clutch coupling on each drive axle. The clutch is mounted
inline on the drive axle between the drive wheel and the
drive motor gear box. The clutch is designed to slip at a
pre-set torque if the machines rear wheels are over-driven
while the machine is being towed, pushed or forklifted,
thus preventing damage to the drive gear box. Although
factory pre-set, the clutch assembly and torque should be
checked at the following interval:
2. Select a torque wrench capable of setting a torque
of at least 185 ft. lb. Insert special tool (P/N0080229) into a 3/4" socket on the torque wrench.
3. Slide the tool onto the end of the drive axle aligning
the key on the axle shaft (install key on axle, if necessary), with key slot in the tool. (See Figure 2-2.)
4. Turn the torque wrench and note the torque setting
when the torque limiting clutch releases. The torque
(slip) setting should be set at 185 ft. lb. Check both
rear drive axles.
• Every 3 months.
Visual Inspection and Limiting Torque
Checking Procedure
NOTE: The allowable breaking torque for the torque limiting
clutch can be set as much as 35 ft. lb. less than the
factory setting of 185 ft. lb., but never more than the
185 ft. lb. factory setting.
1. Locate the machine on a firm level surface.
KEEP MACHINE LEVEL OR SLIGHTLY TILTED TOWARD FORKLIFT
TRUCK WHEN LIFTING TO PREVENT MACHINE FROM SLIDING
OFF LIFTING TINES.
2. Carefully raise the lift to gain access to the underside of the base frame. Refer to Section 2.4, "Positioning Lift For Access to Components Located
Under the Base Frame".
3. Locate the clutch assembly on each rear drive axle
and check for the following;
5. If torque setting is OK, re-install the wheels and
lower machine, IF NOT, see the following note.
NOTE: If torque setting is outside the allowable range of
specifications, the torque limiting clutch will need
adjustment. See Torque Limiting Clutch Adjustment
following.
SERVICE TOOL
P/N-0080229
(REQUIRES A 1-3/4” SOCKET)
a. Check the coupling chains for any loose or missing parts, i.e. pins, links, etc., replace if necessary.
b. Check that the allen-head set screws on the
(large) clutch adjusting nut are in place and
secure. Tighten or replace if necessary.
c. Check for any debris wedged in or wrapped
around the clutch coupling chains and axle
shafts. Remove debris and clean area if necessary.
TORQUE
LIMITING
CLUTCH
LOCATION
Figure 2-2. Check Torque Limit Clutch Torque Setting.
3120728
– JLG Lift –
2-5
SECTION 2 - SERVICE PROCEDURES
Torque Limiting Clutch Adjustment
Drive Motor Brake Adjustment/Removal
NOTE: The large adjusting nut on the side of the clutch
assembly is a standard type thread.
If the torque (slip) setting of the clutch assembly is
under spec (by more than 35 ft. lb.), the large adjusting nut must be (tightened) turned clockwise to
increase the torque setting.
If the torque (slip) setting is over spec (over 185 ft.
lb.) the large adjusting nut must be (loosened),
turned counter-clockwise to decrease the torque setting.
1. Loosen the two (2) adjusting nut setscrews located
on the large adjusting nut on the clutch assembly.
(See Figure 2-3.)
2. Hold the drive axle steady using service tool (P/N0080229) and the torque wrench used to check the
torque setting.
3. Depending on how far off the original torque setting
was (see note at beginning of this procedure),
tighten or loosen the adjusting nut accordingly, then
recheck the (slip) torque setting.
(See Figure 2-4. & Figure 2-5.)
Mounted onto the front of each drive motor housing is a
brake assembly. The brakes are normally ENGAGED
(brakes on) when the machine is parked and are
RELEASED electrically (brakes off) under normal driving
conditions, when the joystick is enabled and pushed in
any direction. The brakes can also be RELEASED manually using the manual brake release lever mounted on the
side of the mast.
NOTE: The brakes are intended only as parking brakes to
keep the machine from moving while at rest. The
brakes are not used to stop the machine during driving operations, this braking is controlled by the drive
motors themselves. Under normal driving conditions,
once released the brakes are not engaged again
until the machine comes to a complete stop.
MANUAL
BRAKE
RELEASE
ARM
MAGNETIC
COIL
HOUSING
4. When proper torque setting is achieved, re-tighten
the two (2) adjusting nut, setscrews.
5. Re-install the drive wheels, remove the jack stand
and lower the machine to ground.
LIMIT
(MICRO)
SWITCH
MOUNTING
PLATE
ARMATURE
PLATE
ADJUSTING NUT
SET SCREWS
FRICTION
BRAKE
DISK
TORQUE LIMIT
CLUTCH
ADJUSTING NUT
SPRINGS
SHIM WASHERS
(AS REQUIRED)
SPACER
Figure 2-3. Torque Limit Clutch Adjustment Components.
2-6
Figure 2-4. Brake Assembly Components
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
FRICTION BRAKE DISK
FRICTION BRAKE DISK
MOUNTING PLATE
ARMATURE PLATE
MAGNETIC COIL
(Not Energized)
MANUAL
RELEASE ARM/
ADJUSTMENT
SCREW
MOUNTING PLATE
ARMATURE PLATE
0.006” GAP
BETWEEN
ARMATURE
PLATE AND
MAGNETIC COIL
MAGNETIC COIL
(Energized)
MANUAL
RELEASE ARM/
ADJUSTMENT
SCREW
0.020” GAP
UNDER
SCREW HEAD
BETWEEN
ARMATURE
PLATE
0.006” GAP
BETWEEN
FRICTION
DISK AND
ARMATURE
PLATE
0.026” GAP
UNDER
SCREW HEAD
BETWEEN
ARMATURE
PLATE
GAP SETTINGS - BRAKE RELEASED
(Magnet Energized)
GAP SETTINGS - BRAKE ON
(Magnet Not Energized)
Figure 2-5. Brake Armature Plate & Brake Disk Adjustment.
Operation (See Figure 2-4. & Figure 2-5.)
3. With the brakes ENGAGED measure the air gap
between the armature plate and the magnetic coil
housing. The correct setting should be .006", however the brakes will operate properly if the measurement is a minimum of .004" and a maximum of .010".
(See Figure 2-5.)
When the magnetic coil is not energized (brake on), the
armature plate is pushed away from the magnetic coil surface by heavy springs internally mounted in the magnetic
coil housing. This pressure forces the armature plate
against the friction brake disk holding it tight between the
armature plate and the mounting plate. The brake is not
released until either the magnetic coil is energized pulling
the armature plate away from the friction brake disk or the
brake is manually released using the manual brake
release handle.
4. If the air gap falls outside the maximum allowable
setting of .010" the friction disk has worn. To correct
this replace the disk with a new one.
5. It the air gap is below the minimum allowable setting
of .004", recheck the areas between the magnetic
coil housing, armature plate, friction disk and
mounting plate for debris. Clean as neccessary. Also
check that the manual release arm screws are not
tightened to tight.
A correctly adjusted brake will ideally have a measurment
of approximately .006" (but will operate normally at .004" to
.010") between the armature plate and magnetic coil
housing surface when the brakes are ENGAGED (brakes
on).
Never allow any type of lubricant (oil, grease, hydraulic
fluid, etc.) to come in contact with the brake friction disk or
it’s contacting surfaces. Also if the brake becomes
clogged with debris or dirt the brake may not release
properly.
Manual Release Arm - Screw Adjustment
NOTE: Always check the armature plate gap setting is within
spec before attempting to adjust the manual release
arm screw adjustment.
Checking/Adjusting Armature Plate Gap Setting
1. First inspect that all parts of the brake assembly are
tight and secure. Tighten as necessary.
2. Inspect the brake for any debris which may be
lodged in the air gap between the armature plate
and magnetic coil when the brakes are ENGAGED
(brakes on); on either side of the friction disk when
the brake is RELEASED (brakes off); or any dirt or
debris lodged between the manual release arm and
the magnetic coil housing. Clean and remove debris
as necessary.
3120728
– JLG Lift –
1. With the brakes ENGAGED (brakes on) the air gap
under the head of the manual release arm screw to
the surface of the armature plate should be set at
.020". Adjust using the locknut on the release arm
end of the screw.
2. With the brakes electrically RELEASED (brakes off)
the air gap under the screw head increases to
approximately .026" due to the armature plate movement towards the magnetic coil, releasing the friction brake disk. When the brakes are RELEASED
(brakes off) manually the screw head pulls in against
the armature plate releasing the friction brake disk.
2-7
SECTION 2 - SERVICE PROCEDURES
Brake Assembly Removal
6. Reconnect the manual release brake cable to the
manual release lever (Y shaped lever) and adjust
cable so brakes are released when manual release
lever is in the down position. (See Figure 2-6.)
1. Lift the machine to gain access to the underside
(See Section 2-4., "Positioning Lift For Access To
Components Located Under The Base Frame").
2. Disconnect the brake magnetic coil wiring connector
and the brake limit (micro) switch wiring connector
from their wiring harness connectors.
3. Disconnect the manual brake release cable from the
manual brake release arm attached to the brake
assembly.
MANUAL
RELEASE
BRAKE
CABLE
4. Lower machine back down to ground level.
TO MANUAL
RELEASE
BRAKE
HANDLE
MOUNTED
ON SIDE OF
MAST
PLACE MACHINE ON A LEVEL SURFACE BEFORE BEFORE
REMOVING THE BRAKE ASSEMBLIES. MACHINE MAY ROLL
AWAY IF NOT SETTING ON A LEVEL SURFACE.
5. Using the Ground Control Switch, raise the platform
to gain access to the brake assemblies mounted on
the end of the drive motors located at the base of the
mast.
NEVER WORK UNDER AN ELEVATED PLATFORM UNTIL PLATFORM HAS BEEN SAFELY RESTRAINED FROM ANY MOVEMENT
BY BLOCKING OR OVERHEAD SLING.
6. Remove the four (4) hex cap screws securing the
brake assembly to the end of the drive motor and
remove the brake assembly from the end of the
drive motor.
SET MANUAL
BRAKE RELEASE
HANDLE TO
FREE WHEELING
AND ADJUST HERE
UNTIL BRAKE DISK
IS COMPLETELY
RELEASED
BRAKES
ARE RELEASED
WHEN CABLE
PULLS LEVER
IN THIS DIRECTION
Figure 2-6. Manual Release Brake Cable Adjustment.
Brake Assembly Installation
1. Guide the manual release lever, brake coil and brake
limit switch wiring connectors through the opening
in the drive motor cover and base frame while sliding the brake assembly onto the front of the drive
motor. Engage the teeth of the disk brake with the
teeth on the drive motor brake gear.
2. If necessary, manually release the brake disk using
the manual release lever to allow the brake assembly to turn and align the four holes in the brake
mounting plate with the mating holes in the drive
motor end plate.
3. Secure the brake assembly to the drive motor using
four (4) hex cap screws with washers. Torque evenly
to 44 in. lbs.
4. Lift the machine to gain access to the underside
(See Section 2-4., "Positioning Lift For Access To
Components Located Under The Base Frame").
5. Reconnect the brake coil and brake limit switch wiring connectors to their respective wiring harness
connectors.
2-8
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Drive Motor Removal
5. Disconnect the wiring connectors to the drive motor
and the brake assembly on either or both sides,
depending on which drive assembly(ies) is being
removed.
(See Figure 2-7.)
The VP drive motors consist of three sections, the gear
box atttached to the rear of the drive motor, the electric
drive motor itself, and the brake assembly mounded at the
front of the drive motor. Each drive motor is mounted independently of the other on a completely removable drive
assembly weldment at the back of the machine.
1. Disconnect the positive battery terminal from the left
side battery.
6. Disconnect the manual release brake cable from the
brake assembly arm on either or both drive motors if
removing the complete drive assembly.
NOTE: If removing each drive motor seperately continue to
Step 7. If removing the complete drive assembly
with both motors attached go to Step 11.
2. Remove the rear plate weldment from the machine,
(plate with the tie down lug) and set aside. Three (3)
bolts hold the top of the rear plate weldment to the
base frame, four (4) bolts attach it to the motor cover
weldment (located under machine) at the back and
on the sides.
7. Remove the one (1) bolt, nut, and two (2) washers
from the front of the drive motor mounting plate.
3. Carefully raise the lift to gain access to the underside of the base frame. Refer to Section 2.4, "Positioning Lift For Access to Components Located
Under the Base Frame".
9. Slide the drive motor and torque limiting clutch
assembly towards the center of the machine, sliding
the torque limiting clutch off the outer drive shaft.
4. Remove the remaining two (2) bolts attaching the
motor cover to the base frame and set it aside.
8. While holding the drive motor in place, remove the
remaining two (2) bolts with washers holding the
drive motor mounting plate to the drive motor
assembly weldment.
10. Move drive motor assembly and torque limiting
clutch to a suitable work bench for disassembly.
DRIVE MOTOR
ASSEMBLY
WELDMENT
ATTACH BOLTS
DRIVE MOTOR/
DRIVE MOTOR
BRAKE WIRING
ASSEMBLY WELDMENT
CONNECTORS
(2 EACH INSIDE FORK LIFT POCKET)
MANUAL
RELEASE
BRAKE
CABLE
DRIVE MOTOR MOUNT
PLATE FASTENERS
(THREE ON EACH MOUNT
ALSO SEE INSET)
DRIVE MOTOR
COVER
DRIVE MOTOR MOUNT
PLATE
REAR PLATE
WELDMENT
Figure 2-7. Drive Motor Assembly Removal.
3120728
– JLG Lift –
2-9
SECTION 2 - SERVICE PROCEDURES
Gear Box Disassembly/Assembly
IF REMOVING THE COMPLETE DRIVE ASSEMBLY, IT WEIGHS
APPROXIMATELY XX LB. AND WILL REQUIRE ASSISTANCE TO
LOWER. PREFERABLY USE A MOVABLE TRANSMISSSION OR
OTHER HYDRAULIC JACK TO CAREFULLY LOWER ASSEMBLY
FROM UNDER MACHINE.
11. Carefully remove the four (4) nuts and washers
(outer most holes on the drive assembly weldment)
from the carriage bolts attaching the drive motor
assembly to the base frame. Be aware of the weight
of the assembly before completely removing the fasteners, see the CAUTION above.
12. Lower the drive assembly and place on a suitable
work surface.
(See Figure 2-8.)
The drive motor gear box is mounted on the rear of each
drive motor transferring power from the electric drive
motor to the rear drive wheels. It is a right angle worm
gear type box with a 50:1 reduction drive ratio. The internal gears and bearings of the gear box are lubricated by
175cc’s of gear oil in an unvented aluminum alloy housing. Early VP machines included a oil drain plug on the
rear surface of the gear box housing, later model
machines do not. The following procedures disassemble
and assemble the gear box housing internal components.
Gear Box Disassembly (See Figure 2-8.)
1. Remove the drive motor/gear box/brake assembly
from the machine using the procedure outlined previously in this section of the manual.
Figure 2-8. Drive Motor Gear Box Assembly.
2-10
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
NOTE: The gear oil can be drained out when the side cover
is removed in the next step. Remove the side cover
from the gear box with the drive shaft side pointing
down, then tilt drive motor/gear box assembly to
drain the oil into a suitable container.
2. Remove the four (4) hex cap screws securing the
side cover to the gear box housing, and remove the
side cover and rubber seal ring. (Note: Early model
machines did not have the rubber seal ring and were
sealed with sealant only.) Be careful not to scratch or
gouge the mating surfaces between the cover and
the gear box housing. This area is sealed by the rubber ring/sealant and may leak oil if damaged.
Gear/Pinion Shaft Assembly (See Figure 2-9.)
1. Locate the pinion gear/shaft, place the key for the
(brass) worm gear into the slot on the gear shaft.
2. Press the (brass) worm gear onto the pinion shaft
and align the keyway in the (brass) worm gear with
the key on the pinion shaft. Press the (brass) worm
gear onto the shaft until it bottoms out against the
pinion gear teeth.
NOTE: Press bearings onto the shaft pressing only against
the bearing inner race. Do not press against the
outer race or damage could occur to the bearing.
3. Press the small (32mm) bearings onto the ends of
the pinion shaft. The inner race of the bearing on the
pinion gear side can be bottomed out against the
pinion gear. Do not press the bearing on the (brass)
worm gear side of the shaft in tight against the
(brass) worm gear. This bearing must be flush with
the end of the shaft on the outside, yet have clearance from the (brass) worm gear on the inside, so it
can rotate freely.
3. Remove the wave washers from atop the large and
small bearings and lay inside their respective holes
in the side cover.
4. Using a suitable catch container, drain the gear oil
from the gear box housing.
5. Remove the drive shaft assembly from the housing.
Place the drive motor/gear box assembly on a
hydraulic press with the open side of the gear box
housing facing down. Support the gear box housing
surface but do not block the free travel of the drive
gear and bearings, on the drive shaft or the pinion
gear assembly.
Drive Shaft Assembly (See Figure 2-10.)
6. With the open surface of the housing properly supported, carefully press the drive shaft down through
until it is free of the housing. When the drive shaft
assembly is free, slide it completely out of the housing.
7. To remove the large (47mm) (cover side) bearing
and (housing side) bearing from the drive shaft, use
a suitable hydraulic press and press the bearing(s)
off the shaft. Keep the spacer from between the
cover side bearing and the drive shaft gear for reuse
during assembly.
1. Slide the (housing side), 42mm x 25mm x 12mm
(thinner) bearing onto the long end of the drive shaft.
Press the bearing inner race until it bottoms against
the shaft shoulder between the drive gear and the
bearing.
2. Slide the narrow spacer onto the drive gear end of
the shaft and press the (cover side) 42mm x 20mm x
14mm (wider) bearing onto the drive shaft until it
bottoms against the spacer. This bearing should be
flush with the end of the drive shaft.
SIDE PROFILE
8. To remove the small (32mm) bearing(s) from the
gear (brass) and pinion assembly, use a suitable
hydrauic press and press the bearing(s) off the gear
and pinion shaft.
9. To remove the (brass) worm gear from the pinion
assembly, use a suitable hydraulic press and press
the gear off the pinion shaft. Keep the (brass) gear
key for reuse during assembly.
WORM
GEAR
(BRASS)
32mm
BEARING
PINION GEAR/
SHAFT
LEAVE
GAP HERE
32mm
BEARING
10. Inspect the drive shaft seal for cuts, cracks and
wear, or if showing signs of leakage. Replace if necessary.
WORM GEAR
KEY
Figure 2-9. Gear/Pinion Shaft Assembly.
3120728
– JLG Lift –
2-11
SECTION 2 - SERVICE PROCEDURES
Final Gear Box Assembly
that gear set align the drive shaft bearing and wiggle
it into it’s seat. When both are seated continue to
next step.
1. If necessary, install a new drive shaft lip seal into the
drive shaft hole in the gear box housing before
assembling the drive shaft gear set into the gear
box. Install the seal so it is even with the bottom of
the chamfer in the drive shaft hole on the outside of
the housing and flush with the bearing seat on the
inside of the housing.
6. With the gear box still positoned with the open cover
side up, fill the gear box with six (6) ounces (U.S.)
(175cc’s) of good quality worm gear oil (Specification - SAE 90 weight - AGMA#5 - EP Compounded).
When pouring the gear oil, wet the gears and bearings with the oil.
2. Lube the drive shaft seal with a thin film of oil before
sliding the drive shaft over the seal.
7. Wet with gear oil and place the large wave washer
on the end of the drive shaft bearing and the small
wave washer on the end of the gear and pinion bearing.
3. Position the gear box with open cover side up, allow
space under the gear box for the drive shaft to
extend through without obstruction.
8. Clean the mating surfaces of the side cover and the
gear box and check that the cover dow guide pins
are properly installed in the cover.
4. Hold the gear and pinion, and drive shaft assembies
together with the pinion gear and the ring gear on
the drive shaft meshing. Now carefully slide these
assemblies into the gear box housing sliding the
drive shaft through the drive shaft lip seal.
NOTE: While assembling the gear assemblies into the gear
box housing, be careful with the drive shaft seal and
the softer brass worm gear and brass drive worm
gear from the drive motor.
5. Continue to drop the gear assemblies into the gear
box, align the bearings with the bearing seats in the
housing on both assemblies. Drop the gear and pinion (smaller) bearing into it’s seat first, while wiggling
PINION
GEAR
9. On older model gear boxes apply sealant to the
cover mating surface on the gear box. On newer
model gear boxes insert the rubber seal into the
groove in the cover.
10. Using the cover dow guide pins, place the cover
onto the gear box housing.
11. Secure using the four (4) hex cap screws, torque
screws evenly to 90 in. lbs.
12. Install the drive motor back onto the machine.
PINION GEAR KEY
SPACER
42mm x 25mm x 12mm
BEARING
DRIVE SHAFT
SIDE PROFILE
42mm x 20mm x 14mm
BEARING
Figure 2-10. Drive Shaft Assembly.
2-12
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Brush Removal (See Figure 2-12.)
Drive Motor Brush Replacement
Each drive motor contains two (2) brushes, the brushes
are located under the two (2) large round slotted brush
caps on the front end of each drive motor.
BRUSH CAP
Removal of the brushes also requires the removal of the
drive motor(s) from the machine, see procedure
described earlier in this section for instructions to remove
the drive motors. If not already done, disconnect the positive (+) battery cable from the left side battery before proceding.
1. Unscrew the large round brush caps from each side
of the drive motor, use as large a screw driver as
possible.
DRIVE MOTOR
2. The brushes are retained by constant-force, roll-type
springs. To remove the springs, press inward on the
end of the spring retaining bracket using the tip of a
pair of long nose pliers or other appropriate tool.
The brushes should pop out, if not, they can be
removed by pulling outward on the spring brackets
with a pair of long nose pliers after the inside ends
are unhooked.
BRUSH
ASSEMBLIES
LOCATED
INSIDE
HERE
3. Now pull the brush out of the brush box by it’s wire
(pig-tail).
NOTE: If only inspecting the brushes, it is not necessary to
remove the pig-tail terminal from it’s connection to
the brush box.
BRUSH CAP
BRAKE
ASSEMBLY
4. Loosen the the screw securing the pig-tail terminal
end to the brush box and slide the terminal end out
from under the screw completely removing the
brush from the drive motor.
Figure 2-11. Drive Motor Brush Location.
DISCONNECT THE POWER LEADS FROM THE POWER SOURCE
BEFORE INSPECTING OR REPLACING BRUSHES.
Brush Cleaning and Inspection
Brush wear rate varies depending on the individual application’s duty cycle, and should be inspected at frequent
intervals to determine an appropriate inspection schedule.
Brushes should be replaced before they are less than .375
in. (9.5mm) in length. Carbon dust accumulation should
be removed periodically. If the end shield has been
removed from the drive, a clean, dry, non-linting cloth can
be used for cleaning. DO NOT use solvents as they my
damage non-metallic parts and adversely affect subsequent brush commutation.
SPRING BRACKET
BRUSH BOX
SPRING
BRACKET
HOOKS
BRUSH BOX
INSULATOR
BRUSH
PIGTAIL WIRE
SPRING BRACKET
Figure 2-12. Drive Motor Brush Installation.
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SECTION 2 - SERVICE PROCEDURES
Brush Reassembly (See Figure 2-12.)
MAKE CERTAIN THAT THE GROUND WIRE IS SECURELY RECONNECTED TO THE GROUND TERMINAL IF REMOVED. LEADS,
INTERNAL TO THE SHEILD, MUST BE ROUTED AWAY FROM THE
ARMATURE, (E.G.: BE CLOSE TO THE INSIDE WALL OF THE
ALUMINUM SHIELD) TO PREVENT A SAFETY HAZARD AND/OR
DAMAGE TO THE MOTOR.
1. Install the brush (pig-tail) terminal end under the
screw on the brush box in the same manner as the
old brush that was removed and tighten the screw.
2. Slide the body of the brush into the brush box, be
certain that the wire (pig-tail) is aligned with the slot
in the base of the brush box so that it can "feed" into
the brush box slot as the brush wears down.
NOTE: The pig-tail wire should be formed to rest against the
nonmetallic insulator. It must be spaced from any
metallic surfaces other than the brush box by a minimum of .125 in. (3mm).
CORRECT
INCORRECT
Figure 2-13. Correct/Incorrect Brush Spring Bracket
Positions.
THE SPRING BRACKET MUST BE ALSO LIE COMPLETELY INSIDE
THE BRUSH BOX AND NOT OUT OVER THE EDGE. THE ROLL
END OF THE SPRING MUST BE CENTERED ON THE TOP OF THE
BRUSH. (SEE FIGURE 2-13.)
3. Now install the brush retaining spring bracket. Grasp
the tip of the spring bracket such that the roll-type
spring will be on the "brush side" of the brush box,
and resting on top of the brush when the brush
spring is completely installed.
4. Push the spring bracket slowly into it’s slot while letting it’s two attaching hooks slide on the wall of the
brush box.
5. Stop, but do not release the spring bracket when it’s
hooks slip around the edge of the brush box.
6. While still grasping the spring bracket with the pliers,
slowly bring the spring back out of the brush box
until the hooks latch around the edge of the brush
box.
8. Also apply slight pressure by pulling up on the
spring bracket to be certain it is hooked securely
around the brush box wall at the bottom of the brush
box.
9. Screw the brush caps back into the end shield using
the largest possible screwdriver.
10. Reinstall the drive motor(s) to the machine and
reconnect the power source.
NEW BRUSHES MAY BE SEATED BY RUNNING THE DRIVE
MOTOR AT NO LOAD. PROPER SEATING IS REQUIRED FOR
LOWEST BRUSH NOISE LEVEL.
7. Now release the spring bracket and check that it is
lying flat against the brush box wall. If it is "cocked" it
is improperly seated and will have to be reinstalled.
2-14
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
2.6
3. Turn on power to the platform control, nine (9) LED’s
will flash rapidly on the platform control touch pad.
PLATFORM CONTROL BOX SERVICE
PROCEDURES
4. Depress the horn switch pad, the alarm will sound
for about one (1) second, then release the horn pad.
Joystick Calibration Procedure
5. Now release the joystick to the neutral position.
1. Turn off all power to the platform control.
6. Turn off system power.
2. Move the joystick to the maximum forward position
and hold it there.
The joystick calibration is now complete.
NOTE: Joystick will be held in the maximum forward position
until asked to release it in Step 5.
JOYSTICK ASSEMBLY
S/N- 02996 TO PRESENT
(INCLUDES DRIVE ENABLE BUTTON)
UPPER
HOUSING
TOUCH PAD
SWITCH
JOYSTICK
ASSEMBLY
PRIOR TO
S/N- 02996
(USED THE
TOUCH PAD
ENABLE
SWITCH)
INTREGRATED
CIRCUIT
BOARD
LOWER
HOUSING
SPEED
CONTROL
KNOB
EMERGENCY
STOP SWITCH
BUTTON
SPEED
CONTROL
SWITCH
EMERGENCY
STOP SWITCH
Figure 2-14. Platform Control Box Assembly (Exploded View)
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SECTION 2 - SERVICE PROCEDURES
Lower Half Of Housing Removal
Platform Control Box Disassembly
1. Position the control box upside down and remove
the six (6) screws attaching the lower half of the
housing to the upper half of the control box housing.
DO NOT ATTEMPT TO DISASSEMBLE THE PLATFORM CONTROL
BOX IF MACHINE IS STILL UNDER WARRANTY. OPENING THE
PLATFORM CONTROL BOX WHILE THE MACHINE IS UNDER
WARRANTY WILL VOID THE WARRANTY. IF UNDER WARRANTY
REQUEST A REPLACEMENT BOX FROM THE FACTORY.
2. Lay screws and lower housing aside.
The VP Series platform control box allows for replacement
of five (5) components internal to the box.
• Controller Integrated Circuit Board
• Joystick Assembly
• Emergency Stop Switch
• Speed Control Switch
• Touch Pad Switch Assembly
Except for the touch pad switch assembly, which plugs
into the circuit board, replacement of each component
requires unsoldering, then soldering each replacement
components’ wiring to the controller’s integrated circuit
board. Due to the small contact area when connecting
each wire to the circuit board this soldering requires precise temperatures and neatness of the soldered point
itself so as not to destroy the circuit board or cross any of
the circuit paths on the board.
Joystick Assembly Removal
NOTE: To completely remove the joystick assembly, its wiring will need to be unsoldered from the intregrated
circuit board.
ELECTROSTATIC DISCHARGE CAN DAMAGE COMPONENTS ON
THE INTEGRATED CIRCUIT BOARD. PLACE THE PLATFORM
CONTROL BOX ON A NON-CONDUCTIVE SURFACE WHEN OPENING THE BOX AND WORKING DIRECTLY WITH THE CIRCUIT
BOARD.
1. Remove the four (4) screws from the top of the bezel
around the base of the joystick and slide the joystick
assembly out of the upper housing.
2. Unplug the touchpad switch ribbon connector from
the circuit board connector socket.
Removing Control Box From Platform
1. Turn off all power to the platfom control box.
2. Unhook the wiring harness cable at the quick-disconnect coupling. (Early VP models were not
equipped with the quick-disconnect coupling, skip to
Step 4.)
3. Remove the platform control box and box mount to
a suitable work surface.
4. Remove the control box from the control box mount
by removing the four (4) nuts from the studs on the
bottom of the control box.
5. Unplug the wiring harness cable connector on the
back of the lower housing half.
6. Lay control box mount and wiring harness assembly
aside.
2-16
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
3. Remove the four (4) screws attaching the circuit
board to the upper housing.
Emergency Stop Switch Removal
1. Remove the switch part of the emergency stop
switch by carefully prying upward at the corner of
the switch using a straight blade screwdriver. This
will seperate the switch from the reset button part of
the emergency stop button assembly.
NOTE: If reusing the circuit board be careful when unsoldering component wires DO NOT OVERHEAT BOARD.
4. Position the circuit board and unsolder the wires
from the joystick assembly at the J2, J3 and J7 locations on the circuit board. (See Figure 2-15.)
NOTE: (VP model joystick assemblies prior to S/N- 02996
did not have the drive enable button on the joystick
knob. Wires from this design were attached in the J3
location on the circuit board only.)
2. Position the circuit board and locate the emergency
stop switch wires connected at locations J8, J9, J10
and J11. Unsolder the four (4) wires to the switch to
remove the switch from the board. (See Figure 2-15.)
5. With all the joystick wiring unsoldered remove joystick assembly from the control box.
J8 - J9
J10 - J11
EMERGENCY
STOP
SWITCH
(4 WIRES)
J2 - J7
JOYSTICK
WIRING
(2 WIRES)
(Later Models With
Enable Button On
Knob Only)
J3
JOYSTICK
WIRING
(5 WIRES)
TOUCHPAD
SWITCH
CONNECTOR
SOCKET
J5
SPEED
CONTROL
SWITCH
(3 WIRES)
Figure 2-15. Platform Control - Circuit Board Component Wiring Connections.
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2-17
SECTION 2 - SERVICE PROCEDURES
3. Remove the reset button part of the emergency stop
switch by unscrewing the collar on the inside end of
the reset button assembly.
Touch Pad Switch Removal
1. Unplug the touch pad ribbon cable connector from
the circuit board connector socket. (See Figure 215.)
2. Using a thin tool, start by lifting an edge of the touch
pad switch and slowly peel away it from the face of
the upper housing until completely free.
Speed Control Switch Removal
1. Remove the speed control knob by pulling up on the
knob until it is free of the switch shaft.
2. Loosen and remove the retaining nut and lock
washer from the switch collar and pull the switch out
of the housing.
Platform Control Box Assembly
To assemble the components back into the control box
follow the previously outlined disassembly procedure and
reverse the steps for the component being installed. The
following are additional guidelines for assembling each
component.
NOTE: Be careful when soldering component wires to the
circuit board DO NOT OVERHEAT BOARD.
Joystick Installation
1. Use the following illustrations to reattach the wires
from the joystick to the circuit board.
3. Position the circuit board and locate the speed control switch wires connected at location J5. (See Figure 2-15.) Unsolder the three (3) wires to the switch
to remove the switch from the platform box.
J3
CIRCUIT BOARD
COMPONENT SIDE
YELLOW
BLUE
BLACK
RED
WHITE
WIRES FROM JOYSTICK
CONTROL
2-18
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Speed Control Switch Installation
1. Use the following illustrations to reattach the wires
from the speed control switch to the circuit board.
WIRES
FROM
JOYSTICK
CONTROL
(Later Model
Joystick
w/Drive
Enable
on Knob)
WHITE (light gauge)
YELLOW (light guage)
CIRCUIT BOARD
COMPONENT SIDE
CIRCUIT BOARD
COMPONENT SIDE
ORANGE
WHITE W/ORG
GREEN
2. If damaged replace the gasket between upper housing surface and the joystick mounting surface before
assembling.
J5
WIRES FROM SPEED
CONTROL SWITCH
Emergency Stop Switch Installation
1. Use the following illustration to reattach the wires
from the emergency stop switch to the circuit board.
Touch Pad Switch Installation
1. Thoroughly clean the surface of the upper housing
where the touch pad switch adheres to the upper
housing.
2. Remove all traces of silicone sealant from around
the slot where the ribbon cable connector passes
through the housing.
CIRCUIT
BOARD
COMPONENT
SIDE
RED (PIN 21)
BLACK (PIN 13)
BLACK (PIN 14)
RED (PIN 22)
WIRES FROM
EMERGENCY
STOP SWITCH
2. If damaged replace the gasket between the stop
switch base plate and the upper housing mounting
surface.
APPLY SILICONE
SEALANT HERE
IN THIS SLOT
3. Remove the adhesive backing off the new touch pad
switch, keep this surface clean and free of debris
during assembly.
4. Assemble the new touch pad switch to the upper
housing surface by first sliding the ribbon cable con-
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– JLG Lift –
2-19
SECTION 2 - SERVICE PROCEDURES
nector from the touch pad switch through the slot at
the top of the housing. Before pressing the touch
pad adhesive side to the upper housing mounting
surface, visually align the touch pad edges with the
edges of the recess in the housing mounting surface.
5. Once the touch pad is installed, on the underside of
the housing apply just enough silicone sealant to fill
the small slot around the ribbon cable to help seal
the slot and also strengthen the ribbon cable connection at the touch pad surface.
6. Re-install the circuit board and plug the ribbon cable
connector into the circuit board cable socket.
Lower Half Housing Installation
1. Before installing the lower half housing apply a nonconductive grease to the square holes of the wiring
harness connector socket on the inside of the housing socket. This will help keep out dirt and moisture.
2.7
BATTERY CHARGER ASSEMBLY AND
DISASSEMBLY
General Information
DO NOT ATTEMPT TO DISASSEMBLE THE BATTERY CHARGER
IF MACHINE IS STILL UNDER WARRANTY. OPENING THE BATTERY CHARGER WHILE THE MACHINE IS UNDER WARRANTY
WILL VOID THE CHARGER WARRANTY. IF UNDER WARRANTY
REQUEST A REPLACEMENT CHARGER FROM THE FACTORY.
ALSO BE FORE REPL AC ING ANY COMPO NENT, USE TH E
CHARGER MANUFACTURERS TROUBLESHOOTING GUIDE
INCLUDED WITH THE MACHINE FOR CHECKING THE INTERNAL
AC AND DC CIRCUITS TO DETERMINE WHICH COMPONENT HAS
FAILED. COMPLETE WIRING DIAGRAMS PERTAINING TO YOUR
MODEL CHARGER ARE ALSO INCLUDED IN THE MANUFACTURERS CHARGER MANUAL.
The VP Series battery charger allows for replacement of
the following internal components. Consult your Illustrated
Parts Manual for part numbers of these components
which are available from the JLG Parts Department:
WIRING HARNESS
CONNECTOR SOCKET
• Transformer
• Printed Circuit Board
• Shunt Assembly
• Interlock Relay
• SCR Rectifier
• AC Circuit Breaker
• DC Circuit Breaker
Replacement and troubleshooting of these components
requires removal of the battery charger from it’s mounting
position on the machine.
Battery Charger Removal
1. Remove the rear cover from the machine.
2. Carefully slide the lower housing onto the upper half
of the platform control box assembly until seated
completely against the upper housing edges.
3. Secure lower half housing to the upper half housing
using the six (6) screws removed during dissassembly.
2. Unbolt and lower the MC-1 Controller Box.
3. Remove the four (4) capscrews securing the charger
to it’s mounting plate.
4. Disconnect the DC wiring from the positive/negative
battery terminals and interlock connector from the
wiring harness.
5. Remove the charger from the machine.
2-20
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Printed Circuit Board Replacement
Battery Charger Part Replacement
1. Disconnect the wide wiring connector from the end
of the circuit board.
Cover Removal
1. Remove the eight (8) screws on the sides of the
charger cover and remove cover.
2. Remove the four (4) screw attaching the card to the
front face of the charger chassis.
3. Remove the circuit board.
Shunt Assembly Replacement
Transformer Replacement
1. Disconnect the wiring connecting the the transformer to other components within the charger
assembly.
1. Carefully remove the screw from each end of the
shunt assembly. The white insulator may need to be
restrained to keep it from turning while removing the
shunt assembly fasteners. Also make note of the
position of each washer, nut and wire connector
when removing for later assembly.
2. Remove the four nuts from the cap screws securing
the transfromer brackets to the base of the charger
chassis.
3. Remove transformer.
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SECTION 2 - SERVICE PROCEDURES
AC Circuit Breaker Replacement
Interlock Relay Replacement
1. Disconnect the wiring connected to the relay.
1. Disconnect wiring connected to the breaker poles.
2. Remove the two (2) nuts securing the interlock relay
to the chassis base.
2. Remove the two (2) nuts securing the AC breaker to
the chassis screws.
3. Remove the relay.
3. Remove the breaker from the chassis.
SCR Rectifier Replacement (Either Side)
1. Remove the wiring from the SCR Rectifier.
2. Remove the nut securing the rectifier to the insulated
aluminum chassis bracket.
DC Circuit Breaker Replacement
3. Remove the SCR Rectifier.
1. Remove the wiring from the DC breaker terminals.
2. To remove the breaker from the front face of the
charger, on the inside of the charger front face, push
in on the tabs located on the sides of the breaker
assembly and remove the breaker out the front of
the charger.
LOCKING
TABS
2-22
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
2.8
HYDRAULIC LIFT CYLINDER REMOVAL, INSPECTION AND REBUILD
HYDRAULIC CYLINDERS ARE DESIGNED TO HOLD HYDRAULIC
FLUID UNDER HIGH PRESSURE. BE SURE ALL APPROPRIATE
MEASURES ARE TAKEN TO RELIEVE RESIDUAL PRESSURE IN
THE CYLINDER BEFORE DISCONNECTING LINES.
Lift Cylinder Removal
Removal of the hydraulic lift cylinder without removing the
mast from the machine requires laying the machine on it’s
back (hood side) with the platform end on top.
1. Remove the hood from the rear of the machine.
2. Disconnect and remove the batteries from the
machine, to prevent acid leakage.
AVOID DAMAGE TO
CONTROLS IN
THIS AREA
3. Seal the vented cap on the hydraulic fluid reservoir
by removing the cap, covering the hole with a few
layers of plastic wrap or equivalent, then install and
tighten the cap over the plastic wrap.
NOTE: If a quick-change platform is attached to the machine
remove the platform to help reduce the weight of the
machine during machine lay back.
4. Use a forklift truck or overhead crane and carefully
lay the machine on it’s back, place a support under
the mast end. (See Figure 2-16.)
5. Manually extend the mast assembly approximately
two (2) feet, to allow access to the sheave wheelanchor block at the top of mast section-2.
Figure 2-16. Machine Positioned for Cylinder
Removal.
Cylinder Disassembly
1. Before disassembling the cylinder, clean away all
dirt and foreign substances from openings, particularly the head area.
NOTE: Always protect the chrome surface of the cylinder
rod during assembly and disassembly. Any damage
to this surface will require replacement of the rod.
2. Extend the rod until the piston bottoms out against
the cylinder head.
6. Remove the set screw securing the lift cylinder rod
to the sheave wheel anchor block at the top of mast
section-2.
3. Compress the head retraining ring enough to allow
the the cylinder head to be removed.
7. Under the base assembly remove the four (4) bolts
attaching the PHP bar actuator assembly to the lift
cylinder mount. Secure the assembly out of the way.
4. Carefully slide the head/rod/piston assembly out of
the cylinder tube. A gentle tap on the head assembly
may be required to remove the head from the cylinder tube.
8. Carefully disconnect and cap the extend and return
lines and fittings from the lift cylinder, drain any
hydraulic fluid into a container.
5. Place the head/rod/piston assembly on a surface
that will not damage the chrome.
9. Remove the bolt securing the lift cylinder to the cylinder mount.
10. Remove the four (4) bolts, washers and nuts attaching the cylinder mount to the base frame. Remove
the mount and lay aside.
11. At the bottom of mast section 2, slide the lift cylinder
assembly out and place on a suitable work surface.
SUPPORT
MAST
6. Remove the piston locknut and separate the piston
from the rod.
7. Slide the head off the rod from the piston end.
NOTE: When removing the old seals use only blunt tools, be
sure there are no sharp edges that may damage the
seal grooves during removal. Scratching the groove
may cause by-pass.
8. Remove and discard all old seals.
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2-23
SECTION 2 - SERVICE PROCEDURES
Lift Cylinder Component Inspection
Cylinder Assembly
Cylinder Rod
(See Figure 2-17.)
There should be no scratches or pits deep enough to
catch the fingernail. Pits that go to the base metal are
unacceptable. Scratches that catch the fingernail but are
not to the base metal, less than 0.5 inch long and primarily
in the circumferential direction are acceptable provided
they cannot cut the rod seal. Chrome should be present
over the entire surface of the rod and the lack thereof is
unacceptable. In the event that an unacceptable condition
occurs, the rod should be repaired or replaced.
1. Rinse the inside of the tube with hydraulic fluid and
allow to drain. A high-pressure rinse followed by a
wipe with a lint-free rag is preferable. Clean all internal components of any foreign material.
2. Lubricate the head and all seals with hydraulic fluid
prior to installation. Install the seal, wiper, o-ring,
back-up ring, and retraining ring to the cylinder
head.
3. Lubricate the piston and all components with
hydraulic fluid. Install the seal and wear ring to the
piston.
Cylinder Head
Visually inspect the inside bore for scratches or polishing.
Deep scratches are unacceptable. Polishing indicates
uneven loading and when this occurs, the bore should be
checked for out-of-roundness. If out-of-roundness exceed
0.007", this is unacceptable. Check the condition of the
dynamic seals (wiper, rod seals) looking particulary for
metallic particles embedded in the seal surface. It is normal to cut the static seal on the retaining ring groove upon
disassembly. Remove the rod seal, static o-ring and
backup and rod wiper. Damage to the seal grooves, particularly on the sealing surfaces, is unacceptable. In the
event that an unacceptable condition occurs, the head
should be replaced.
NOTE: Re-check that seals are not twisted or pinched and
are properly seated.
4. Place the rod on a clean table. Install the static oring seal into the groove on the piston end of the
rod.
5. Install the head followed by the piston onto the rod
noting the proper orientation of each component.
Torque the piston nut to 175-200 ft. lbs.
6. When the rod assembly is ready to be installed into
the tube, liberally apply an anti-seize lubricant to the
head outer surface, especially the static seal.
7. Next dip the entire rod assembly into hydraulic fluid
and stuff this assembly into the tube. Watch the
seals as they pass over the rod port (if visible) to be
sure they are not nicked or cut.
Piston
Visually inspect the outside surface for scratches or polishing. Deep scratches are unacceptable. Polishing indicates uneven loading and when this occurs, the diameter
should be checked for out-of-roundness. If out-of-roundness exceeds 0.007", this is unacceptable. Check the condition of the dynamic seals and bearings looking
particularly for metallic particles embedded in the bearing
and in the piston seal surface. Remove the seals and
bearings. Damage to the seal grooves, particularly on the
sealing surfaces, is unacceptable. In the event that an
unacceptable condition occurs, the piston should be
replaced.
8. Install the head until the retaining ring seats in it’s
groove.
Cylinder Installation
To install the lift cylinder reverse the Lift Cylinder Removal
instructions at the start of this section, however perform
the following additional steps during re-assembly.
Tube Assembly
Visually inspect the inside bore for scratches and pits.
There should be no scratches or pits deep enough to
catch the fingernail. Scratches that catch the fingernail but
are less than 0.5 inch long and primarily in the circumferential direction are acceptable provided they cannot cut
the piston seal. The roughness of the bore should be
between 10 and 20 µ inches RMS. Significant variation
(greater than 8 µ inches difference) are unacceptable. In
the event that an unacceptable condition occurs, the tube
assembly should be repaired or replaced.
2-24
– JLG Lift –
1. Apply Loctite #222 (purple) to the setscrew securing
the lift cylinder rod to the sheave wheel anchor block
at the top of mast section-2.
2. Torque the four (4) cylinder lift mounting bolts to 34
ft. lb.
3120728
SECTION 2 - SERVICE PROCEDURES
RETAINING RING
GROOVE
WEAR
RING
PISTON
SEAL
O-RING
O-RING
CYLINDER
HEAD
RETAINING
RING
BACKUP
RING
ROD
SEAL
ROD
WIPER
CYLINDER
TUBE
ASSEMBLY
LOCKNUT
(Torque
175-200 Ft. Lb.)
PISTON
WHEN ASSEMBLING
CYLINDER
APPLY ANTI-SEIZE
COMPOUND
AROUND THE HEAD
IN THIS AREA ONLY
CYLINDER
HEAD
CYLINDER
ROD
Figure 2-17. Lift Cylinder Internal Component Assembly Cross-Section.
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– JLG Lift –
2-25
SECTION 2 - SERVICE PROCEDURES
2.9
MAST ASSEMBLY AND DISASSEMBLY
PROCEDURES
The VP Series personnel lift mast sections are contructed
of extruded aluminum, protected with an anodized surface
finish. The mast sections are interlocked into each other
when assembled, by internally mounted slide pads at the
top and bottom of each mast section. These slide pads
run up and down in slide pad channels on each side of
the mast.
tions even). Applying silicone spray onto the slide pads
and slide pad channels before assembly will help mast
sections slide easier after slide pads have been properly
shimmed.
Mast Disassembly Procedure
NOTE: Reference to mast sections-3/-4/-5 (platform mounting section) depends on which VP model lift you are
working on.
Each VP model mast assembly contains a different number of mast sections as shown following;
1. After the mast assembly has been removed from the
machine, lay the mast assembly down on a suitable
work table with the platform mounting section on
top, facing up.
Table 2-2. VP Series Mast Component Features
Model
No. of Mast
Sections
Extend/Retract
Device
10VP
3
Cable
15VP
4
Cable
20VP
5
Chain & Cable
2. Remove the sequencing cables and hardware from
the sides of the mast assembly. Also remove the
cover from the top of the mast assembly.
Assembly procedures for all mast sections is basically the
same, carefully slide the mast sections together from bottom until mast ends are even. (When sliding the mast sections together, be careful not to scratch the anodized
surface). Assemble the hardware to the bottom of mast
section first, slide this section out the top of previous section and assemble hardware to the top of mast, (See Figure 2-1.). Always install slide pad shims with slide pads
inserted into the slide pad channels, (ends of mast sec-
3. Remove cable adjust nuts from threaded ends of
cable attached to the cable anchor plate on BOTTOM end of mast section-3/-4/-5 (platform mounting
section). Push threaded ends of cable through
anchor plate.
4. At the TOP of mast section—3/-4/-5, pull cables out
and allow to hang loose.
NOTE: When sliding mast sections apart, be careful not to
scratch or score the anodized surface in the slide
pad channels.
OPEN RAIL
(REFERS TO OPEN RAIL
FRONT OF MAST SECTION)
TOP
(REFERS TO TOP END
OF MAST SECTION
WHERE COVER AND
SHEAVE WHEELS
ARE ATTACHED)
BOTTOM
CLOSED RAIL
(REFERS TO BOTTOM END OF
MAST SECTION WHICH SETS IN
MACHINE’S BASE FRAME)
(REFERS TO CLOSED RAIL
BACK OF MAST SECTION)
Figure 2-18. Mast Section - Assembly Reference.
2-26
– JLG Lift –
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SECTION 2 - SERVICE PROCEDURES
5. Carefully slide mast section-3/-4/-5 out BOTTOM of
mast section-2/-3/-4 rails. Disassemble slide pads,
shims and cable anchor plate from mast section-3/4/-5, if necessary.
15. While mast section-3 is still extended from section-2
remove the bolts attaching the two (2) cable assembly anchor eyelets to the TOP of mast section-3.
Remove cables.
NOTE: Steps 6 through 10 apply to removal of mast section4 on model 20VP lifts which have five (5) mast sections. If servicing a 15VP mast, go to step 11, or a
10VP go to step 17.
NOTE: When sliding mast sections apart, be careful not to
scratch or score the anodized finish in the slide pad
channels.
6. Remove cable adjust nuts from threaded ends of
cables attached to the cable anchor plate on bottom
end of mast section-4. Push threaded ends of
cables through anchor plate.
7. At top of mast section-4, pull cables out and allow to
hang loose.
8. Slide mast section-4 out the TOP of mast section-3
far enough to allow access to the cable sheave
wheel assembly.
9. Remove countersunk-flathead screws securing
cable sheave wheel assembly attach bars on both
side rails at top of mast section-4 and remove
sheave wheel assembly.
NOTE: When sliding mast sections apart, be careful not to
scratch or score the anodized finish in the slide pad
channels.
10. Carefully slide mast section-4 out BOTTOM of section-3. Remove slide pads, shims and cable anchor
plate, if necessary.
NOTE: Steps 11 through 16 apply to removal of mast section-3 on 15VP (cable actuated) & 20VP (cable/chain
actuated) lifts. If servicing a 10VP mast, go to step
17.
11. Remove cable/chain adjust nuts from threaded ends
of cable/chain attached to the cable/chain anchor
plate on BOTTOM end of mast section-3. Push
threaded ends of cable/chain through anchor plate.
12. At TOP of mast section-3, pull cables/chains out and
allow to hang loose, (be certain floor surface is clean
and free of any metal chips or debris which may stick
to lubricated chains).
13. Slide mast section-3 out TOP of mast section-2 far
enough to allow access to the cable/chain sheave
wheel assembly.
14. Remove countersunk-flathead screws securing
cable/chain sheave wheel assembly attach bars on
both side rails at TOP of mast section-3 and remove
the sheave wheel assembly.
16. Carefully slide mast section-3 out BOTTOM of section-2. Remove slide pads, shims and chain anchor
plate, if necessary.
NOTE: Removal of mast section-2 (cylinder attach section)
is basically the same for all VP model lifts except
where noted.
17. Slide mast section-2 out TOP of mast section-1 far
enough to allow access to the cable/chain assembly
anchor block/sheave wheel assembly.
18. Remove countersunk-flathead screws securing
cable/chain anchor block/sheave wheel assembly
attach bars on both side rails at TOP of mast section-2.
19. Slide the cable/chain anchor block/sheave wheel
assembly and hydraulic cylinder out the TOP of
mast section-2 far enough to allow removal of the
sheave wheel attach bars, sheave wheels and
sheave pin from cable/chain assembly anchor
block.
20. Remove the setscrew holding the hydraulic cylinder
rod into the chain assembly #444 anchor block. Lay
chain assembly #444 to side.
21. Remove the hydraulic cylinder through BOTTOM of
mast section-2, be careful not to nick or score cylinder rod surface while removing.
NOTE: When sliding mast sections apart, be careful not to
scratch or score the anodized finish in the slide pad
channels.
22. Carefully slide mast section-2 out BOTTOM of section-1. Remove slide pads and shims, if necessary.
23. Slide the TOP of remaining mast section-1 out over
edge of work surface and remove the bolts attaching
the cable/chain anchor blocks to mast section-1.
Remove cable/chain assemblies from mast and lay
aside.
24. Remove slide pads and shims from mast section-1.
Mast disassembly should now be complete.
NOTE: Step 15 applies only to 20VP lift models which have
five (5) mast sections. If servicing a 15VP mast, go
to step 16.
3120728
– JLG Lift –
2-27
SECTION 2 - SERVICE PROCEDURES
Figure 2-19. 10VP Mast Assembly.
2-28
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Figure 2-20. 15VP Mast Assembly.
3120728
– JLG Lift –
2-29
SECTION 2 - SERVICE PROCEDURES
Figure 2-21. 20VP Mast Assembly.
2-30
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Mast Assembly
sure there are no air gaps (on flat side of slide
pad) between shims, shim and mast or shim and
slide pad when tightened.
(See Figure 2-18., 2-19., 2-20. & 2-21.)
1. Place mast section-1, rail (open) side up on a clean,
flat surface (preferably a table or work bench capable of supporting the weight of the entire mast
assembly). Slide mast out over end of work surface
far enough to allow access to the chain anchor
attach holes at top of mast.
c. All mast sections are to be shimmed to provide a
measurable gap between the slide pad (beveled
side) and mast channel of 0.012" to 0.025" per
side.
d. When mast slide pads are shimmed properly,
the mast sections should be able to slide in
channel by hand.
2. Locate the two (2) single cable/chain assemblies.
Lay out each cable/chain assembly with anchor
block end towards mast, and threaded end away
from mast, (be certain floor surface is clean and free
of any metal chips or debris which may stick to lubricated chains).
8. Insert slide pads into the slide pad channels (top of
mast) between section-1 and -2, (one on each side
of the mast), with beveled surface facing in towards
section-2.
9. Thread slide pad attaching bolts, (two (2) 1/4"20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt), through holes in
mast section-1 outside rail (top of mast) and into the
slide pad inserts. Thread in enough to hold pad in
place.
3. Insert the block anchor end into the top of mast section-1 and secure using two (2) 3/8"-16UNC x 2-1/2"
(chain) 1-1/4" (cable) long hex head bolts, flatwashers and nuts for each attach block. Place a flatwasher under bolt head and nut.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
10. Shim per instructions in step 7.
4. Locate mast section-2, carefully slide mast section-2
closed rail into section-1 open rail. Slide sections
together until ends are even.
NOTE: If hydraulic cylinder needs to be extended, the protective caps on the extend and return ports will need
to be removed. Be careful not to nick or scour rod
surface when extending, also catch any oil draining
out of cylinder to avoid spillage onto work area.
NOTE: Do not attach mast slide pads and shims to mast
sections before assembling sections. If assembled in
this manner, due to the tight fit of the slide pads in
the slide pad channels, the anodized finish could be
removed from the receiving mast’s slide pad channels.
11. Locate the hydraulic lift cylinder, slide the lift cylinder
into the closed rail side of mast section-2 with rod
end to top and port end to bottom of mast. Cylinder
should extend out of mast on both ends. Return
tube should be on right side when facing bottom of
mast assembly.
5. Insert slide pads into the slide pad channels at bottom end of mast between section-1 and -2, (one on
each side of the mast), with beveled surface facing
out towards section-1.
NOTE: Top of cylinder assembly steps 12 and 13 applies to
20VP only. For 10VP & 15VP continue to step 14.
6. Thread slide pad attaching bolts, (two (2) 1/4"20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt), through holes in
mast section-2 inside rail, into the slide pad inserts.
Thread in enough to hold pad in place.
7. Shim slide pads using the following steps:
NOTE: Always use the an even amount of shim material
behind slide pads on both sides of the mast rails.
This will keep mast sections centered in rail channels and prevent any distortion of the mast section.
a. Use two shim pieces per slide pad, a thick one
and a thin one.
12. Locate chain assembly #444 (single anchor block
with two narrow chains). Lay out chain assembly
with anchor block end towards mast, (be certain
floor surface is clean and free of any metal chip or
debris which may stick to lubricated chains).
13. Insert hydraulic cylinder rod end into chain assembly #444, anchor block. Secure cylinder rod to
anchor block with a 1/4"-28UNF x .50" long - Type C
setscrew. Coat threads with blue Loctite # 242
before assembly.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad rails.
b. Start with a total thickness of approximately a
.025" thick shim and a .055" thick shim.Slide
shims into place between slide pad and mast
rail. Tighten the slide pad mounting bolts, be
3120728
– JLG Lift –
a. Locate mast section-3, carefully slide section-3
closed rail into section-2 open rail. Slide sections together until ends are even. Locate one
(1) of the chain/cable anchor plates (one with
threaded holes horizontally aligned to outside of
2-31
SECTION 2 - SERVICE PROCEDURES
bracket). Attach using outer set of holes in bottom of mast section-3 with two (2) 1/4"-20UNC x
3/4" long bolts, place a flatwasher under head of
each bolt.
f. On outside of spacer tubes place a sheave pin
attach bar, (rectangular plate with threaded holes
on each side of pin bore hole).
g. Before sliding this assembly into the top of mast
section two, locate two (2) mast extension cable
assemblies and lay their anchor ends into the
slots of the cable mounting tube.
14. Slide mast section-3, approximately two feet out of
the top of mast section-2.
15. Insert threaded ends of cable/chain-assembly #466
(attached to top of mast section-1), through holes in
anchor plate attached to bottom of mast section-3.
Loosely thread two (2) 3/8"-16UNC nuts onto stud
threads on each chain. Cables/chains will be
adjusted later in assembly.
16. Slide mast section-2 out of mast section-1 approximately one foot.
10VP Top of Cylinder Assembly
19. Assemble cable sheave wheels to cylinder rod end
and attach to mast section-2 using following steps;
h. Slide the assembly with sheave pin, wheels and
pin attach bars into top of mast section-2.
i. Attach to top of mast section-2 using two (2) 3/
8"-16UNC x 1/2" long socket head-countersunkflathead cap screws each side. Coat threads
with Loctite #171 and tighten.
20VP Top of Cylinder Assembly
19. Assemble chain sheaves on chain assembly #444
anchor block (attached to cylinder rod end) and
attach to mast section-2 using following steps;
a. Insert sheave pin through anchor block on cylinder rod end.
a. Attach cable mounting tube to top of hydraulic
cylinder using one (1) 1/4"-28NF x 5/8" capscrew.
b. Place sheave wheels (for wide chain) on sheave
pin, one each side of anchor block.
b. Insert sheave pin through cylinder cable mounting tube on cylinder rod end.
c. On outside of each sheave wheel, place a
sheave pin attach bar, (rectangular plate with
threaded holes on each side of pin bore hole).
c. Place a spacer tube on each side of mounting
tube.
d. Slide the whole anchor block assembly with
sheave pin, wheels and pin attach bars into top
of mast section-2. (Position anchor block with
narrow chains facing mast section-3).
d. Next slide sheave wheels on onto sheave pin
against spacer, on each side of mounting tube.
e. On outside of each sheave wheel, place another
spacer tube.
e. Attach to top of mast section-2 using two (2) 3/
8"-16UNC x 1/2" long socket head-countersunkflathead cap screws each side. Coat threads
with Loctite #171 and tighten.
f. On outside of spacer tubes place a sheave pin
attach bar, (rectangular plate with threaded holes
on each side of pin bore hole).
g. Slide the assembly with sheave pin, wheels and
pin attach bars into top of mast section-2.
h. Attach to top of mast section-2 using two (2) 3/
8"-16UNC x 1/2" long socket head-countersunkflathead cap screws each side. Coat threads
with Loctite #171 and tighten.
15VP Top of Cylinder Assembly
19. Assemble cable sheave wheels to cylinder rod end
and attach to mast section-2 using following steps;
a. Attach cable mounting tube to top of hydraulic
cylinder using one (1) 1/4"-28NF x 5/8" capscrew.
b. Insert sheave pin through cylinder cable mounting tube on cylinder rod end.
NOTE: Step 23 and 24 applies to 20VP mast assembly only.
10VP and 15VP mast assembly continue at step 25.
21. Locate two mast extension cable assemblies. Attach
the eyelet anchor end of each cable to the outside
holes near top of mast section-3 using 3/8"-16UNC x
1-1/4" long hex head bolts, nuts and flatwashers.
Place a flatwasher under bolt head and nut.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
d. Next slide sheave wheels on onto sheave pin
against spacer, on each side of mounting tube.
22. Carefully slide mast section-3 into section-2 until
ends are even. Check to make sure chain assembly
#466 (wide chains) are seating properly in chain
#444 anchor block chain sheave wheels attached to
mast section-2.
e. On outside of each sheave wheel, place another
spacer tube.
NOTE: Do not attach mast slide pads and shims to mast
sections before assembling sections. If assembled in
c. Place a spacer tube on each side of mounting
tube.
2-32
20. Slide mast section-2 back into section-1 until end
are even.
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
this manner, due to the tight fit of the slide pads in
the slide pad channels, the anodized finish could be
removed from the receiving mast’s slide pad channels.
23. Insert slide pads into the top end mast rails between
section-2 and -3, (one on each side of the mast),
with beveled surface facing inward towards section3.
24. Thread slide pad attaching bolts, (two (2) 1/4"20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt), through holes in
outside rail, on top of mast section-2 and into the
slide pad inserts. Thread in enough to hold pad in
place.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
33. Slide mast section-4 back into mast section-3 except
for about a foot or more. Allow enough slack in
cables/chains to mount sheave wheels to top of
mast section-3.
34. Extend mast section-3 out far enough from section-2
mast to gain access to top of section-3.
35. Assemble cable/chain sheaves to top of mast section-3 as follows;
a. Locate the two cable/chain sheave wheels and
slide onto sheave pin.
b. Slide two (2) short spacer tubes onto sheave
pin, one each end of sheave pin to outside of
sheave wheels.
25. Shim per instructions in step 7.
26. Insert slide pads into the bottom end mast rails
between section-2 and -3, (one on each side of the
mast), with beveled surface facing out towards section-2.
c. Place two (2) sheave pin attach bars, one each
end of sheave pin to outside of space tubes.
d. Holding complete sheave wheel assembly, slide
assembly into top of mast section-3 and align
threaded holes in sheave pin attach bars with
holes in mast rails.
27. Thread slide pad attaching bolts, (two (2) 1/4"20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt), through holes on
inside rail, on bottom end of mast section-3 and into
the slide pad inserts. Thread in enough to hold pad
in place.
e. Attach to top of mast section-3 using two (2) 3/
8"-16UNC x 1/2" long socket head-countersunkflathead cap screws, each side. Coat threads
with Loctite #171 and tighten.
28. Shim per instructions in step 7.
NOTE: Assembly of 10VP mast should now be complete. To
continue with 15VP assembly go to step 48. 20VP
assembly continues following.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
36. Slide mast section-3 back into section-2 until ends
are even. (Mast section-2 may need to be restrained
to keep its slide pads from pushing out the bottom
of mast section-1).
29. Locate mast section-4, carefully slide section-4
closed rail into section-3 open rail. Slide sections
together until ends are even.
30. Locate one (1) of the chain/cable anchor plates (one
with two threaded holes vertically aligned in center of
bracket). Attach through inner (vertical) set of holes
at bottom of mast section-4 using two (2) 1/4"20UNC x 3/4" long bolts, place a flatwashers under
head of each bolt.
31. Slide mast section-4 out the top of mast section-3 so
the chain/cable anchor plate on bottom of mast section-4 is easily accessible at top end of mast section3. Rest the top end of mast section-4 on a support
while performing next step.
37. While mast section-4 is still extended from section-3;
locate two cable assemblies. Attach the eyelet
anchor end of each cable to the inside set of holes
near top of mast section-4 using 3/8"-16UNC x 1-1/4"
long hex head bolts, nuts and flatwashers. Place a
flatwasher under bolt head and nut.
38. While mast section-4 is still extended from section-3,
assemble cable sheaves to top of mast section-4 as
follows;
32. Insert threaded ends of cable/chain assembly
(attached to anchor block on top mast section-2)
through the chain/cable anchor plate located on bottom of extended mast section-4. Loosely thread two
(2) 3/8"-16UNC nuts onto stud threads on each
chain. Chains will be adjusted later in assembly.
3120728
– JLG Lift –
a. Locate the wide tube spacer and slide onto
sheave pin.
b. Slide two (2) cable sheave wheels onto sheave
pin, one each end of sheave pin to outside of
tube spacer.
c. Place two (2) large flat washers, one each end of
sheave pin to outside of cable sheave wheels.
d. Place two (2) sheave pin attach bars, one each
end of sheave pin to outside of large flatwashers.
2-33
SECTION 2 - SERVICE PROCEDURES
e. Holding complete cable sheave wheel assembly, slide assembly into top of mast section-4
and align threaded holes in sheave pin attach
bars with holes in mast rails.
f. Attach to top of mast section-4 using two (2) 3/
8"-16UNC x 1/2" long socket head-countersunkflathead cap screws, each side. Coat threads
with Loctite #171 and tighten.
46. Locate the remaining mast section-4/-5 (platform
mounting- mast section). Lay mast section on flat
stable surface.
47. Attach the remaining chain/cable anchor plate (one
with threaded holes vertically aligned in center of
bracket). Attach through inner (vertical) set of holes
in bottom of mast section-4/-5 with two (2) 1/4"20UNC x 3/4" long bolts, place a flatwasher under
head of each bolt.
NOTE: When sliding mast sections together, be careful not
to scratch or score the anodized finish in the slide
pad channels.
48. Complete the following steps to determine shim
stock thickness required for section-4/-5;
39. Carefully slide mast section-4 back into section-3
until ends are even. Check to make sure cable/chain
assemblies are seating properly in cable/chain
sheave wheels attached to top of mast section-3.
NOTE: Always use the an even amount of shim material
behind slide pads on both sides of the mast rails.
This will keep mast sections centered in rail channels and prevent any distortion of the section.
NOTE: Do not attach mast slide pads and shims to mast
sections before assembling sections. If assembled in
this manner, due to the tight fit of the slide pads in
the slide pad rails, the anodized finish could be
removed from the receiving mast’s slide pad channels.
a. Use two shim pieces per slide pad, a thick one
and a thin one.
40. Insert slide pads into the top end mast rails between
section-3 and -4, (one on each side of the mast),
with beveled surface facing inward towards section4.
b. Start with a total thickness of approximately
.035" and .075" thick shim stock.
NOTE: To protect the anodized finish when sliding the
assembled mast section-4/-5 into section-3/-4, grind
top and bottom edges of slide pads to approximately
a 1/4" radius.
c. Attach shim stock and slide pads to both sides
of mast section-4/-5 using five (5) 1/4"-20UNC x
1-1/4" long, hex head cap screws per side, with
flatwasher under each bolt head. (Assemble
shim stock and slide pad to mast section rail with
shim stock against rail and slide pad with beveled side out).
41. Thread slide pad attaching bolts, (two (2) 1/4"20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt), through holes in
outside rail, on top of mast section-3 and into the
slide pad inserts. Thread in enough to hold pad in
place.
d. Carefully thread the slide pad mounting bolts
with flatwashers through slide pads and shim
stock into threads in mast section-4/-5. Be certain there are no air gaps between shims, shim
and mast or shim and slide pad when tightened.
42. Shim per instructions in step 7.
43. Insert slide pads into the bottom end mast rails
between section-3 and -4, (one on each side of the
mast), with beveled surface facing out towards section-3.
44. Thread slide pad attaching bolts, (two (2) 1/4"20UNC x 3/8" long hex head bolts, place a flat
washer under head of each bolt), through holes on
inside rail, on bottom end of mast section-4 and into
the slide pad inserts. Thread in enough to hold pad
in place.
45. Shim per instructions in step 7.
NOTE: When sliding mast section-4/-5 into section-3/-4 note
amount of force required to push sections together.
Fit should be very snug but still be able to be pushed
together by hand. If too tight, remove section-4/-5,
disassemble slide pad from section-4/-5 and reduce
thickness of shim stock. Open rails of section-3/-4
may be sprayed with silicone spray to help section-4/
-5 slide easier.
NOTE: The platform mounting section (section—4 on 15VP
and section-5 20VP machines) slide pads, are
assembled differently than the slide pads for the
other mast sections. Mast section-4/-5 slide pads
may need to be assembled/disassembled several
times in order to determine the correct shim stock
required for proper fit.
2-34
– JLG Lift –
e. Begin sliding top of mast section-4/-5 with
closed rail down engaging the slide pads into
slide pad channels at bottom of mast section-3/4’s open rail. Continue to push section-4/-5 into
section-3/-4 until BOTTOM ends of mast sections are even.
f. Check mast section for side play. If play exists
use thicker shims dividing thickness equally
between both sides of mast.
3120728
SECTION 2 - SERVICE PROCEDURES
g. When mast slide pads are shimmed properly,
there should be no side to side movement of
slide pad in rail channel. Mast sections should
be very snug in channels but still be able to slide
in channel by hand.
49. Slide mast section-4/-5 to top of section-3/-4.
50. Insert threaded ends of cable assembly (attached to
top of mast section—2/3) through the chain/cable
anchor plate located on bottom of extended mast
section-4/-5. Loosely thread two (2) 3/8"-16UNC
nuts onto stud threads on each chain. Chains will be
adjusted later in assembly.
2.10 MAST TO BASE FRAME INSTALLATION
IF BATTERIES ARE STILL MOUNTED, REMOVE BATTERIES FROM
THEIR TRAYS BEFORE LAYING THE BASE FRAME IN A HORIZONTAL POSITION.
1. Using an overhead crane or suitable lifting device
capable of supporting the weight of the base frame,
attach a sling strap or chain to the front crossmember of the base frame. Carefully tilt the base frame
back until the front is pointing up and the back is
resting on the counterweight/battery trays. Be sure
base is very stable and at a 90° angle to work surface before proceeding.
51. Slide mast section-4/-5 back into mast section-3/-4
until bottom ends of masts are even. Check to make
sure cable set attached to top of section-2/-3 is seating properly in cable sheave wheels attached to top
of mast section-3/-4. (Mast sections-2, -3 and -4 may
need to be restrained to keep their slide pads from
pushing out the bottom of mast sections-1, -2 and 3).
2. Using a sling and suitable lifting equipment (i.e.
overhead crane) lift the mast assembly (balanced in
middle) into position in front of the base frame.
3. Extend hydraulic cylinder out from bottom of mast
assembly approximately one (1) foot. (Caps on
extend and return ports will need to be removed to
extend cylinder. Catch any hydraulic fluid expelled
from return port in a container to prevent spillage
onto work area).
52. At bottom of mast assembly, thread all chain/ cable
adjusting nuts on threaded ends until they are snug
against the anchor plates and all slack is removed
from chains and cables. Check that chains and
cables are seated in their sheave wheels at top of
mast assembly. Also, ends of mast sections should
be even with each other.
4. Carefully position the mast into base frame assembly, (base frame and mast assembly must be held at
90° angle to each other).
Mast assembly should now be complete.
5. Slide port end of hydraulic cylinder through hole in
base frame cylinder mounting channel. (Return port
(tube side) of cylinder must be on right side facing
bottom of base and mast).
6. Align threaded hole in side of hydraulic cylinder
head with hole in tab on bottom side of cylinder
mounting channel. Secure hydraulic cylinder to cylinder mounting channel tab using a 5/16"-18UNC x
5/8" long hex head bolt and flat washer.
7. Carefully push mast assembly and base assembly
together until the four (4) holes on bottom rear of
mast align with holes in the base frame mast support
crossmember.
8. Attach mast to base using four (4) 3/8"-16UNC x 1"
long hex head bolts, locknuts and flatwashers,
(place a flatwasher under bolt head and nut and
mount with nuts on inside of frame).
9. Locate the two (2) mast support braces, attach to
sides of base frame using a 3/8"-16UNC x 1" long
hex head bolt, nut and flatwashers each brace,
(place a flatwasher under bolt head and nut and
mount with nuts on inside of frame. Use access hole
in bottom of frame to attach nut inside frame).
10. Before setting machine upright on base, install a
short 90° elbow fitting, flow control valve and
another short 90° elbow fitting on the end of the flow
3120728
– JLG Lift –
2-35
SECTION 2 - SERVICE PROCEDURES
control valve in the extend (left) port on bottom of
hydraulic cylinder. Install a long 90° elbow fitting on
return (right) port. Use sealant tape on fitting
threads. Cap ports until hydraulic lines are installed.
11. Carefully set machine in an upright position on its
base frame wheels.
12. Locate the mast support bracket. Attach mast support bracket to mounting holes halfway up back of
mast using four (4) 3/8"-16UNC x 2-3/4" long hex
head bolts, locknuts and flatwashers. (Place a flatwasher under bolt head and nut and mount with nuts
on inside of frame).
2.11 MAST CHAINS/CABLES AND
SEQUENCING CABLES ADJUSTMENT
Mast Chain/Cable Adjustment
The intention of this procedure is to assure equal load distribution between the individual chains/cables of a mast
section chain/cable set.
Adjust using the following procedure;
1. With mast retracted, step into the platform and
bounce your weight up and down a few times to be
certain platform is at the bottom of travel. Be certain
all chain/cable sets are seated in their sheaves properly at the top of each mast section.
13. Using a 4 ft. level, ensure the mast is set to vertical
(plumb) on the base frame.
14. When mast is vertical (plumb), attach support
braces, (bolted to base), to the mast support
bracket, (bolted to mast), using 3/8"-16UNC x 2-3/4"
long hex head bolts, nuts and flatwashers. (Place a
flatwasher under bolt head and nut and mount with
nuts on inside of bracket).
15. After securing mast to base frame, using 4 ft. level
again check that mast is vertical (plumb) on base
frame.
2. Then with no load in the platform check the side profile of the top of the mast for the amount of adjustment necessary to make the mast sections even for
mast sections-3 and up. (See Figure 2-22.)
NOTE: Mast section-1 is fixed to the base and mast section2 is attached to the lift cylinder, these sections
require no adjustment.
3. Adjust one mast section at a time starting from the
back (section-3, section-4, etc.) of the mast and
work forward. (i.e.. if three is OK, then jump to four,
etc.)
16. Continue installing remaining components to mast
assembly, (i.e. hydraulic pump/motor/reservoir, battery charger, etc.) until machine is complete.
4. Elevate the platform until the chain/cable anchor
adjust nuts are accessible at the front and bottom of
each mast section.
NEVER WORK UNDER AN ELEVATED PLATFORM UNTIL PLATFORM HAS BEEN SAFELY RESTRAINED FROM ANY MOVEMENT
BY BLOCKING OR OVERHEAD SLING.
5. Start with the mast section which needs adjustment
and loosen the bottom (jam) nut on each chain/
cable.
6. Tighten (to raise mast section), or loosen (to lower
mast section) the adjusting nut against the anchor
plate on each chain/cable. Adjust the nut the
amount required to raise or lower the top of the mast
section so it is even with the previous mast section
when the mast is retracted. Be certain each chain/
cable pair is adjusted to equal tension. (The
threaded end of the chain/cable will need to be
restrained while tightening the adjust nut to keep the
chain/cable from twisting.)
7. Retract the mast all the way and check if the top of
the mast sections appear as shown in Figure 2-22.
8. Repeat steps (1) through (7) for remaining mast sections. ENSURE THAT ALL CHAIN/CABLE PAIRS
HAVE EQUAL TENSION.
2-36
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
MAST SIDE PROFILE
ADJUST UNTIL TOPS OF MAST
SECTIONS ARE EVEN
MAST CHAIN/CABLE ADJUSTERS
MAST COVER
SHOWN REMOVED
SEQUENCE CABLE
ADJUST NUT
SECTION-1
FIXED
TO BASE
SECTION-2
EXTENDED BY
CYLINDER
SECTION-3
EXTENDED BY
CHAIN
SECTION-4
EXTENDED BY
CHAIN/CABLE
SECTION-5
(PLATFORM
HEADER SECTION)
EXTENDED BY
CHAIN/CABLE
CHAIN/CABLE
ANCHOR PLATE
ADJUST NUT
Note: When chain adjustment
is complete, before
tightening the jam nut
against the adjust nut,
apply Loctite #242 to the
threads under the jam nut.
.
JAM NUT
THREADED
CHAIN/CABLE
END
Figure 2-22. Mast Chain/Cable/Sequence Cable Adjustment Components.
9. Once mast section adjustment is completed, apply
loctite #242 to the threads under the (jam) nuts that
were loosened. Then re-tighten the loosened (jam)
nuts until tight against the top (adjust) nut. Chain/
cable should have slight tension but should not be
taut.
2. Tighten nylock-nut just enough to remove excessive
slack from sequencing cable. The springs should
not be compressed more than 25% after adjusting.
3. Run mast through several cycles to verify cable/
chain adjustments and ensure no interference exists
between chain anchor brackets and mast.
Sequencing Cable Adjustment
1. Retract mast completely, and check each sequencing cable on outside of masts for excessive slack.
Adjust only to remove slack from cable.
3120728
– JLG Lift –
2-37
SECTION 2 - SERVICE PROCEDURES
2.12 SEQUENCE CABLE REPLACEMENT KIT
A sequence cable replacement kit is available from the
JLG Parts Department to service broken or worn
sequence cables. This kit consists of a replacement
sequence cable with the threaded (top) end attached
same as the top end of the factory cable. Also included is
a clamp (drum/socket type) to secure the bottom end of
the cable. Use the following procedure to install the
replacement cable and clamp kit.
Remove Old Cable
1. Remove the locking nut from the threaded end of
the cable at the top of the mast and then remove the
spring cap, spring, and spacer washers if installed.
2. Slide the threaded top end out of the upper anchor
bracket, then at the bottom end pull the cable out
though the sheave pulley/anchor bracket until it is
completely clear of the machine.
Clamp Installation (Drum/Socket Type)
THE MANUFACTURER OF THE DRUM/SOCKET CLAMP RECOMMENDS THE USE OF THEIR CABLE CLAMP ASSEMBLY KIT (JLG
P/N - 7023275) TO ASSEMBLE THE CLAMP TO THE WIRE ROPE.
THE KIT CONSISTS OF VISE JAWS TO HOLD THE WIRE ROPE IN
A VISE PROPERLY WITHOUT DAMAGING ANY ROPE STRANDS
AND A PLUG DRIVER TO DRIVE THE PLUG INTO THE CENTER OF
THE WIRE ROPE AND IS ALSO USED TO FORM THE STRANDS OF
THE ROPE DURING ASSEMBLY.
NOTE: The tools in the clamp assembly kit may be frabricated if necessary. The vise clamp consists of vise
jaws with a hole drilled 1/32 in. smaller than the
diameter of the wire rope you are working with (i.e.
1/8 in. rope - 3/32 in. hole.)
The plug driver is a metal tube with a hole in the bottom to allow the strands of the wire rope to be
shaped after the plug has been tapped into the center of the wire rope.
Replacement Cable Installation
1. Be certain the mast is completely retacted and at the
bottom of travel. Check the mast "Side Profile" at the
top of the mast as shown in Figure 2-22., adjust
mast sections to proper height if necessary.
1. Using the recommended vise jaws, clamp the wire
rope into a vise with the bottom edge of the black
mark made on the wire rope resting just above the
vise jaws.
2. To determine where the clamp will be installed at the
bottom of the replacement cable, temporarily
assemble the new replacement cable to the top
cable anchor bracket on the mast using the washers, spring, spring cap and lock nut previously disassembled. Thread the lock nut on until
approximately 1/8 in. (3mm) of threads are exposed.
3. At the bottom of the mast, thread the loose end of
the replacement cable through the proper sheave
pulley and through the hole in the sheave pully/
anchor bracket on the mast section ahead of the
sheave pulley.
4. Grasp the cable and pull on the cable until the
spring at the top of the cable is slightly compressed.
Use a black marker to mark the cable on the top
side of the sheave pully/anchor bracket. This will
determine where the clamp (drum/socket) sleeve will
be positioned on the cable.
2. Twist the sleeve from the clamp kit onto the rope
until it is flat against the vise jaws at the mark made
made on the wire rope.
DO NOT CUT THE CABLE AT THE MARKED POINT ON THE
CABLE THIS IS ONLY USED AS A REFERENCE FOR POSITIONING
THE CABLE SLEEVE WHICH WILL REST AGAINST THE ANCHOR
BRACKET ONCE INSTALLED.
2-38
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
3. Use a suitable tool and cut the cable as shown in the
illustration following. For 1/8 in. cable the recommended length is 5/8 in. past the end of the sleeve.
4. Unlay the cable strands by gently forcing a screwdriver between the outer strands to unlay the cable.
When done properly the outer strands will form a
symmetrical basket. Do not straighten out the spiral
lay of the strands, unlay any wires that make up the
strand, or allow the strands to cross each other
inside the sleeve.
6. Reclamp the assembly in the vise on the flats of the
sleeve. Using the plug driver, a metal tube or pliers,
bend the outer strands toward the center strands
enough that the socket can be slipped over all the
strands.
NOTE: When assembling stainless steel parts all threads
must be coated with a dry lubricant or an anti-sieze
lubricant to prevent seizing.
7. Coat the threads of the socket and sleeve with lubricant and install the socket by twisting it over the
strands of the cable and engage the threads of the
sleeve with the socket. Tighten until four threads or
fewer are visible. If more than four threads are visible, proof load the cable and retighten the socket fitting. (There is no specific requirement for torque.)
5. Install the plug supplied with the kit by placing the
plug in the center of the strands starting with the
small tapered end of the plug. Use a metal tube
(plug driver) and hammer to drive the plug into the
sleeve while assuring that the strands are spaced
somewhat equally around the plug. Drive the plug
until it is firmly seated and no more than 1/3 of the
plug is visible from above the sleeve.
8. Inspect for proper assembly prior to loading the
cable. Strands visible through the inspection hole
are your assurance of a proper assembly.
NOTE: The end of the rope may not be visible in the inspection hole after loading.
9. Install cable on machine and adjust per instructions
shown previously in Section 2.11, MAST CHAINS/
CABLES AND SEQUENCING CABLES ADJUSTMENT.
3120728
– JLG Lift –
2-39
SECTION 2 - SERVICE PROCEDURES
2.13 PREVENTIVE MAINTENANCE AND
INSPECTION SCHEDULE
(See Table 2-2.)
The preventive maintenance and inspection checks are
listed and defined in the following table (See Table 2-2.,
this chapter). This table is divided into two basic parts, the
“AREA” to be inspected and the “INTERVAL” at which the
inspection is to take place. Under the “AREA” portion of
the table, the various systems along with the components
that make up that system are listed. The “INTERVAL” portion of the table is divided into five columns representing
the various inspection time periods. The numbers listed
within the interval column represent the applicable inspection code for which that component is to be checked.
2-40
The checks and services listed in this schedule are not
intended to replace any local or regional regulations that
may pertain to this type of equipment nor should the lists
be considered as all inclusive. Variances in interval times
may occur due to climate and/or conditions and depending on the location and use of the machine.
JLG Industries requires that a complete annual inspection
be performed in accordance with the “Annual Machine
Inspection Report” form. Forms are supplied with each
new machine and are also available from JLG Customer
Service. Form must be completed and returned to JLG
Industries.
JLG INDUSTRIES REQUIRES THAT A COMPLETE ANNUAL
INSPECTION BE PERFORMED IN ACCORDANCE WITH THE
“ANNUAL MACHINE INSPECTION REPORT” FORM.
– JLG Lift –
3120728
SECTION 2 - SERVICE PROCEDURES
Table 2-3. Preventive Maintenance & Inspection Schedule.
AREA ON MACHINE
PLATFORM
INTERVAL
(10 HRS.)
DAILY
(50 HRS.)
WEEKLY
(200 HRS.)
MONTHLY
(500 HRS.)
3 MONTHS
(1000 HRS.)
6 MONTHS
(2000 HRS.)
1 YEAR
Platform Controller (all functions)
1,11
Placards and Decals
1,2
Control Tags
1,2
Electrical Cables
1,8
Handrail and Bar Gate
1,4
MAST
Mast Chains/Cables/and all component parts
1,4,7,9
12
Mast Sections
1,4,7
Mast Sequencing Cables
1,4,7,9
Speed/PHP Limit Switches
1,7,9
BASE FRAME
Batteries
1,3
5
Battery Charge
1
Power Cables To Platform
1,8
Electric Motor/Hydraulic Pump Unit
1
5
Hydraulic Hoses and Fittings
1
5
Hydraulic Oil Reservoir *
3
5
4
Hydraulic Oil Reservoir Breather
6,14
Manual Descent Valve
1,7
Lift Cylinder
1
5,6,13
4
Placards and Decals
1,2
Wheels and Casters
1
8,9
12
Wheel Bearings
8
12
Electric Drive Wheel Motors
1,7
Electric Drive Wheel Gear Box **
Torque Limiting Clutch
1,6,9
Power Switch (Ground Control Box)
1,11
Control Tags
1,2
Hoses and Cables
1,8
Bubble Level Indicator
1,2
* Inspection and Maintenance Code 10 to be performed every two years.
** Maintenance Code 10 to be performed only when serviced, requires 6 oz. (175 cc’s) to fill.
Inspection and Maintenance Codes:
1. Check for proper and secure installation.
8. Check for excessive wear or damage.
2. Check for visible damage and legibility.
9. Check for proper tightness and adjustment.
3. Check for proper fluid level.
10. Drain, clean and refill.
4. Check for any structural damage; cracked or broken
welds; bent/warped surfaces; broken cable strands.
11. Check for proper operation while pump/motor is
running.
5. Check for leakage.
12. Check for proper lubrication.
6. Check for presence of excessive dirt or foreign
material.
13. Check for evidence of scratches, nicks or rust and
for straightness of rod.
7. Check for proper operation and freedom of movement.
14. Check for condition of element; replace as necessary.
3120728
– JLG Lift –
2-41
SECTION 2 - SERVICE PROCEDURES
This page intentionally left blank.
2-42
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
SECTION 3. TROUBLESHOOTING
3.1
GENERAL
This section contains troubleshooting information to be used for locating and correcting most operating problems on a VP
Series Personnel Lift. If a problem should develop which is not presented in this section or which is not corrected by listed
corrective actions, technically qualified guidance should be obtained before proceeding with any maintenance.
3.2
TROUBLESHOOTING INFORMATION
Troubleshooting procedures applicable to the VP machine are listed and defined starting with Section 3.5, TROUBLESHOOTING SECTION - TABLE OF CONTENTS in this chapter of the manual.
Each malfunction within an individual group or system is followed by a listing of probable causes which will enable determination of the applicable remedial action. The probable causes and the remedial action should, where possible, be checked
in the order listed in the tables.
It should be noted that there is no substitute for a thorough knowledge of the equipment and related systems.
It should be recognized that the majority of the problems arising in the machine will be centered in the hydraulic and electrical systems. For this reason, every effort has been made to ensure that all likely problems in these areas are given the fullest
possible treatment. In the remaining machine groups, only those problems which are symptomatic of greater problems
which have more than one probable cause and remedy are included. This means that problems for which the probable
cause and remedy may be immediately obvious are not listed in this section.
The first rule for troubleshooting any circuit that is hydraulically operated and electrically controlled is to determine if the circuit is lacking hydraulic oil and electrical control power. This can be ascertained by overriding the bypass valve (mechanically or electrically) so that oil is available to the function valve, then overriding the function valve mechanically. If the function
performs satisfactorily, the problem exists with the control circuit.
3.3
HYDRAULIC CIRCUIT CHECKS
(See Figure 3-6.)
The first reference for improper function of a hydraulic system, where the cause is not immediately apparent, should be the
Hydraulic Diagram Circuit. The best place to begin the problem analysis is at the power source (pump). Once it is determined that the pump is serviceable, then a systematic check of the circuit components, would follow.
NOTE: For aid in troubleshooting, refer to Figure 3-6. for HYDRAULIC DIAGRAM circuit.
3.4
ELECTRICAL CIRCUIT CHECKS
General
The drive system on the VP series machine requires a microprocessor controlled electrical circuit to operate smoothly and
accurately. All platform control functions are relayed to various machine components (i.e. platform up/down, drive functions,
etc.) through the (MC-1) microprocessor box (mounted under the battery charger support bracket).
To help diagnose any problems with the components associated with the microprocessor, the MC-1 is designed with an
internal fault messaging system which is displayed by LED flash sequences on the platform controller. When operating normally the LED panel on the platform controller (center LED strip) indicates the battery voltage status using ten (10) green
LEDs. If a malfunction occurs to any of the drive components, the platform controller, or the MC-1 unit itself, these LEDs will
flash a fault code (Warning or Error type) to help locate the problem area. The possible causes of fault codes are outlined in
the following sub-sections of this chapter, see Table 3-1 and Table 3-2.
NOTE: For aid in troubleshooting electrical problem, refer to Figure 3-3. for an ELECTRICAL DIAGRAM of the various circuits.
Also a pictorial overview of the Section, see Figure 3-2. “Pictorial Overview of VP Electrical System”.
3120728
– JLG Lift –
3-1
SECTION 3 - TROUBLESHOOTING
LED
INDICATOR
STRIP
Figure 3-1. LED Battery/Fault Code Indicator Strip
on Platform Controller Box.
LED Indicator Strip
When the machine is powered up, all function inputs should be open. If any function is active on power up, all functions will
be made inoperative and a fault will be indicated at the platform controller box LED strip.
This strip has ten (10) green LEDs and is located on the platform controller box between the function touch pad buttons. See
Figure 3-1.
Fault Code Reference Tables
Their are two types of fault codes which can occur to indicate a problem with the machine, these are WARNING codes and
ERROR codes.
The fault codes can occur either at machine power up or during operation of the machine.
WARNING Codes
(See Table 3-1.)
The WARNING will be indicated for 4 seconds and will be repeated every minute if the problem is not corrected. An audible
three beeps indication is given at the beginning of each warning displayed. WHEN A WARNING CODE IS INDICATED THE
MACHINE WILL USUALLY FUNCTION, however some machine functions may be disabled. See Table 3-1. for explanation of
WARNING codes.
ERROR Codes
(See Table 3-2.)
An ERROR is indicated by an audible beep and continuously fast flashing LED bar. The number of fast (rapidly) flashing
LEDs indicate the particular error message. AN ERROR CONDITION WILL DISABLE THE MACHINE until the problem is corrected. The ERROR message is only reset by turning off the system, however if the problem has not been corrected the
ERROR will be indicated again at machine power-up. See Table 3-2. for explanation of ERROR codes.
NOTE: As shown in the following WARNING and ERROR code tables, a specific number of LEDs flashing can indicate more
than one WARNING or ERROR code. These tables suggest specific areas to check as the probable cause for the fault
code which has occured. The fault code number is shown in the first column of the table and the number of LEDs flashing on the platform controller LED strip is shown in the second column of the table.
3-2
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-1. MC-1 WARNING CODES
(Indicated by 3 beeps, then slow flashing LED’s)
WARNING
CODE
LED’S
FLASHING
0
10
Enter Code - Security Code has been activated and
must be entered before operation
Enter Code or deactivate using MC-1 configuration
software.
1
8
Charger Connected
Unplug Charger
3
2
Brake Status Switch Open - Parking brake manually
released
Reset Parking Brake
3
2
Brake manual release lever obstructed (located at
drive motor brake)
Clear obstruction and reset lever
3
2
Defective parking brake status switch (located at
drive motor brake)
Replace Switch
3
2
Defective pin 11 at X105 (BRN wire) connection or
improper wiring
Properly attach wires or pin
3
2
Improper wiring at parking brake status switch
Properly attach wires
3
2
Improper wiring from parking brake status switch to Properly attach wires
ground
4
5
Configuration Lost - Drive Characteristic has
changed
Reprogram using MC-1 software
5
6
Current Measurement faulty - Drive characteristic
may have changed
Cycle on-off and reprogram if necessary
6
7
High Temperature in controller
Reduce power
7
7
Motor Stalled
Check drive wheels and motors
9
1
Battery Low ( < 18v) and power reduced
Charge Batteries
12
9
Speed Control Potentiometer defective
Replace Joystick
13
4
Drive Cutout Input Open - PHP bar must be down to
drive while elevated
Lower PHP
13
4
PHP bar is down, but drive is disabled - Defective wir- Properly attach wire (RED/BLU) or pin 12 of X105
ing at D-connector
connector
13
4
PHP bar is down, but drive is disabled - Defective
ground wiring
Properly attach wires
14
3
PHP bar is down, but drive is disabled - Defective
switch
Replace switch
14
3
Tilt Switch open - Slope greater than 2 degrees
Lower Platform and move to level ground
14
3
No Tilt Switch - open circuit at Pin 2 of X101 (WHT
wire)
Properly attach pin or wire connections
14
3
No Tilt Switch - open circuit to ground
Check ground wire connections (BLK1 wire)
25
----
Joystick E. Stop Counter
Controller Log Only
26
----
Configuration Access Counter
Controller Log Only
3120728
PROBABLE CAUSE
– JLG Lift –
REMEDY
3-3
SECTION 3 - TROUBLESHOOTING
Table 3-2. MC-1 ERROR CODES
(Indicated by rapid LED flashing and periodic beep)
3-4
ERROR
CODE
LED’S
FLASHING
0
8
System Overvoltage - Charger
0
8
System Overvoltage - Driving down long steep grade Operate ground controls to reduce voltage
1
7
Controller Overtemperature
Turn unit off and allow to cool
2
8
Drive Motor Plug - Open Circuit - check connectors
X103 & X104
Properly attach wires or pins A1 & A2
2
8
Drive Motor Plug - Open Circuit - check motor connections at motor
Properly attach wires or pins (WHT & BLK wires)
3
6
Brake Safety Relay
Replace Controller
4
2
Brake Short Circuit
Replace Brake
5
2
Brake Left Open Circuit - D-connectors to X103 &
X104 switched
Switch D-connectors - Left Motor to X103; Right
Motor to X104
5
2
Brake Left Open Circuit - Check pins 3 & 5 of X103
and brake wires
Properly attach wires or pins
5
2
Brake Left Open Circuit - Check brake wires or plug at Properly attach wires or pins
drive motor
6
2
Brake Right Open Circuit - Check pins 2 & 5 of X104
and brake wires
6
2
Brake Right Open Circuit - Check brake wires or plug Properly attach wires or pins
at drive motor
7
2
Brake Open Circuit on one or both brakes
See above
8
9
Switch Short Circuit (Joystick)
Replace Joystick Box
9
6
Power Circuit Defect
Replace Controller
10
1
Battery Low (< 16.5 v)
Charge Battery
11
9
Check pins & wire connections at X102 & joystick
box connector
Properly attach wires or pins
11
9
Joystick defective
Replace Joystick Box
12
8
Check pins & wire connections at X102 & joystick
box connector
Properly attach wires or pins
12
8
Joystick Box
Replace Joystick Box
16
7
Current Limiting - Motor Short Circuit - Gearmotor
defective
Replace Gearmotor
21
6
36v supply
Replace controller
24
5
Configuration Lost
Reprogram using MC-1 software, if error reoccours
then replace controller
25
6
RAM ROM
Replace controller
PROBABLE CAUSE
REMEDY
Unplug Charger
– JLG Lift –
Properly attach wires or pins
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-2. MC-1 ERROR CODES
(Indicated by rapid LED flashing and periodic beep)
ERROR
CODE
LED’S
FLASHING
PROBABLE CAUSE
REMEDY
If voltage @ pin 5 (RED2) of X101 is 20v w/24v @ Battery or if ground controls and operating lift up clears
error:
26
6
Defective main contactor
Replace main contactor
Battery cables loose or corroded
Clean & tighten battery cables
26
6
If 0v @ pin 5 of X101, check connection @ pin 7 &
14 of X102
Properly attach wires or pins
26
6
Connection @ pin 5 of X101 bad
Properly attach wires or pins
26
6
Defective Power Relay
Replace Relay
26
6
Defective Power Relay ground wire
Properly attach wire
27
6
Safety Circuit - Joystick - check pin 6 @ X102 (Red
Wire)
Properly attach wire or pin
27
6
Safety Circuit - Joystick - check pin 3 @ joystick
connector (Red Wire)
Properly attach wire or pin
27
6
Defective Joystick - Normal voltage @ pin 6 of X102 Replace Joystick
(Red Wire): Joystick centered 5v, Joystick not centered 0v
27
6
Safety Circuit - Defective Controller
Replace Controller
28
6
Current Measurement
Replace Controller
29
6
Drive Circuit Left - Defective Controller
Replace Controller
31
6
Drive Circuit Right - Defective Controller
Replace Controller
32
1
Output driver defect - check for short in Hourmeter,
Horn, Alarm or Power Relay
Replace defective component
32
1
Output Driver Defective - Defective Controller
Replace Controller
35
8
Communication Error - Check Pins 5 & 13 of X102
(Orange & Blue Wires)
Properly attach wires or pins
35
8
Communication Error - Check Pins 4 & 5 at Joystick Properly attach wires or pins
(Orange & Blue Wires)
35
8
Defective Joystick
Replace Joystick
35
8
Defective Controller
Replace Controller
36
6
Watch Dog
Replace Controller
38
6
EEPROM
Replace Controller
39
6
Software Error
Replace Controller
3120728
– JLG Lift –
3-5
SECTION 3 - TROUBLESHOOTING
BATTERY
(RIGHT SIDE)
BATTERY
(LEFT SIDE)
(–)
(+)
(+)
TO PUMP
MOTOR
SOLENOID
(–)
HORN
BEACON
ALARM
F
COROM
NN X10
EC 1
TO
R
HOURMETER
TO (—)
BATTERY
TERMINAL
GROUND
CONTROL
BOX
MAIN
CONTACTOR
RELAY
05
X1 R
M C TO
O
FR NNE
CO
CO F
N RO
RE TA M
LA CT
Y OR
PUMP START
CONTACTOR
MANUAL
OVERRIDE/
LIFT DOWN
VALVE
DUMP
VALVE
EARLY
DESIGN
LATER
DESIGN
PUMP/MOTOR
ASSEMBLY
POT-HOLE
PROTECTION
LIMIT
SWITCHES
Figure 3-2. Overview of Standard Electrical System. (Sheet 1 of 2)
3-6
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
LAPTOP COMPUTER
(remove existing connector
at X105 port on the MC-1 controller box
and plug-in the laptop computer.
Requires P/N-2900868 Configuration Kit.)
PLATFORM
CONTROL
BOX
TILT
SENSOR
SWITCH
TO (+)
BATTERY
TERMINAL
USE WIRING
DIAGRAM
FIGURE 3-3.
THIS SECTION
OF THE
MANUAL WITH
THIS PICTORIAL
WIRING DIAGRAM
ELEVATION
LIMIT
SWITCH
TO (—)
BATTERY
TERMINAL
TO
BATTERY
CHARGER
CUTOUT
SWITCH
X105
X101
X104
FROM X101
CONNECTO
R
05
X1 R
M CTO
O
FR NNE
CO
PLATFORM
CONTROLLER
MC-1
CONTROLLER BOX
X103
GROUND
CONTROLS
SWITCH
BRAKE
RELEASE
WIRING
(LIFT UP/LIFT DOWN)
GROUND
CONTROLS
RELAY
EXTERNAL
DRIVE/HORN
RELAY
CONTACTOR
RELAY
BRAKE
RELEASE
WIRING
DRIVE MOTOR
POWER LEADS
BRAKE LIMIT
SWITCH
WIRING
TO MAIN
CONTACTOR
RELAY
DRIVE MOTOR
POWER LEADS
MOTOR/BRAKE
ASSEMBLY
(LEFT SIDE)
MOTOR/BRAKE
ASSEMBLY
(RIGHT SIDE)
Figure 3-2. Overview of Standard Electrical System. (Sheet 2 of 2)
3120728
– JLG Lift –
3-7
SECTION 3 - TROUBLESHOOTING
X102
B+
EMERGENCY STOP
CAN-LO
CAN-HI
CENTER DETECT
B–
EMERGENCY STOP
PIN
15
14
13
5
6
1
7
X103 – LEFT MOTOR
MOTOR 1
MOTOR 2
BRAKE 1
BRAKE2
PIN
A1
A2
5
3
E-STOP SWITCH TO PIN 2
ON METAL BOX AND TO
PIN 1 ON PLASTIC BOX.
PINS USED FOR
COMMUNICATION
TO SERIAL PORT
ON LAPTOP OR PC.
PIN 1 ON METAL JOYSTICK
PIN 2 ON PLASTIC JOYSTICK
JOYSTICK
BOX
7 9 2 6 5 4 3 1 8
X105
RX DO - RECEIVE DATA
TX DO - TRANSMIT DATA
GROUND
LIFT UP
LIFT DOWN
PUMP CONTACTOR
DRIVE CUTOUT
BRAKE STATUS
HORN
ALARMS
HOURMETER
PIN
7
8
13
4
6
5
12
11
15
14
3
RED/BLK
BLU/BLK
YEL
ORG
BLU
RED
BLK
BRN
PIN
A1
3
5
1
2
4
A2
X104 – RIGHT MOTOR
MOTOR 1
MOTOR 2
BRAKE 1
BRAKE 2
24V
LOGIC POWER
EMERGENCY STOP
CAN-L
CAN-H
CENTER DETECT
EMERGENCY STOP SWITCH
0V
X101
B+
B+ CONTROL
MAIN POWER DISCONNECT
ELEVATION SWITCH
TILT CUTOUT
CHARGER INTERLOCK
B–
PIN
A1
A2
5
2
15 8 7 13 5 6 14 1
X102
ORANGE 55-3 (10)
11
X105
BLU/ORN 52-2
BLU/ORN 52-3
A1
3
5
1
X101
YEL/RED 2-3
ORN/RED 49-5
ORN/RED 49-6
A2 4
A2
WHITE
X105
X101
X104
X102
X103
YEL/RED 2-5(10)
YEL/RED 2-2
2
X103
ORANGE 55-9
ORANGE 55-10(10)
4932960 A
TAN 3-1
TAN 55-1
+
LEFT
BRAKE
5 1 2 4 3
ORANGE 55-8
A1
ORANGE 55-7(10)
LEFT
MOTOR
BLU/ORN 52-1
ORN/RED 49-3
TAN 4-1
15 3
WHITE
BLACK
ORN/RED 49-1
5 4 6
ORANGE 55-5
A2
MOTOR
RIGHT
X104
BRAKE
RIGHT
5 1 3 4 2
ORANGE 55-4
MC-1
CONTROLLER
A1
ORANGE 55-6 (10)
14 12
+
BLACK
ORN/RED 49-7
BLACK (10)
END VIEW OF MC-1 BOX
SHOWING X CONNECTOR LOCATION
Figure 3-3. VP Electrical Diagram. (VP Series - Standard)
3-8
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
LEFT PHP
LIMIT SWITCH
ORN/RED 49-2
RIGHT PHP
LIMIT SWITCH
BLACK
A
TRAVEL, DESCENT,
MOTION ALARM
OPTION
BLACK
A
RIGHT BRAKE
LIMIT SWITCH
LEFT BRAKE
LIMIT SWITCH
ORN/RED 49-4
BLACK
A
N.O.H.C.
BLACK 55-2
ORN/RED 49-3
BLU/ORN 52-1
ORN/RED 49-1
N.O.H.C.
TAN 55-1
LIFT UP/DOWN
GROUND CONTROL SWITCH
YEL/RED 2-5
MOTOR
PUMP
FUSE
5 AMP
LIFT DOWN
LIFT UP
YEL/RED 2-6
YEL/RED 2-6
TAN 4-1
YEL/RED 2-6
ORN/RED 49-1
BLU/ORN 52-1
PUMP
CONTACTOR
ORN/RED 49-3
TAN 4-1
TAN 3-1
TAN 55-1
TAN 55-1
HOURMETER
BLU/ORN 52-2 OPTION
BLACK
YEL/RED 2-2
A
87A
HORN
RELAY
YEL/RED 2-4
87
A
86
YEL/RED 2-5
A
YEL/RED 2-5(10)
MAIN
CONTACTOR
87A
85
30
POWER
RELAY
RED 1-1
85
30
A
YEL/RED 2-1
B
YEL/RED 2-7
RED 1-1
BLACK
BLACK
A
EXTERNAL
HORN
OPTION
BLU/ORN
87
52-4
BLACK
86
E-STOP
KEY SWITCH
A
GROUND
CONTROL
RELAY
00000
BLU/ORN 52-3
87
YEL/RED 2-8
86 85
GROUND CONTROL BOX
87A
30
YEL/RED 2-4
5 AMP
FUSE
BLACK
A
A
12V
12V
YEL/RED 2-2
YEL/RED 2-3
ELEVATION / SPEED
CUTBACK SWITCH
ORN/RED 49-5
BLACK
RED (10)
ORN/RED 49-6
A
ORN/RED 49-7
BLACK (10)
YEL/RED 2-5
BLACK (10)
KEY SWITCH
BLACK
A
B
GREEN
WHITE
BLACK
BLACK
CHARGER
1
X
2
3
X
1 = PLATFORM
2 = OFF
3 = GROUND
TILT SENSOR
1.5°
4932960 A
A
Figure 3-3. VP Electrical Diagram. (VP Series - Standard)
3120728
– JLG Lift –
3-9
SECTION 3 - TROUBLESHOOTING
BATTERY
(RIGHT SIDE)
BATTERY
(LEFT SIDE)
(–)
(+)
(+)
(–)
TO PUMP
MOTOR
SOLENOID
BEACON
MASTER ON/OFF
SWITCH
HORN
MAIN
CONTACTOR
RELAY
MOTION
ALARM
80 AMP FUSE
FR
CONOM X101
NEC
TO R
HOURMETER
TO
BATTERY
TERMINAL
GROUND
CONTROL
BOX
5
FROM X10 R
TO
C
E
N
N
O
C
CIRCUIT BREAKER PANEL
PUMP START
CONTACTOR
MANUAL
OVERRIDE/
LIFT DOWN
VALVE
DUMP
VALVE
PUMP/MOTOR
ASSEMBLY
POT-HOLE
PROTECTION
LIMIT
SWITCHES
Figure 3-4. Overview of VP UL-EE Approved Optional Electrical System. (Sheet 1 of 2)
3-10
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
LAPTOP COMPUTER
(remove existing connector
at X105 port on the MC-1 controller box
and plug-in the laptop computer.
Requires P/N-2900868 Configuration Kit.)
PLATFORM
CONTROL
BOX
TILT
SENSOR
SWITCH
TO +
BATTERY
TERMINAL
USE WIRING
DIAGRAM
FIGURE 3-3.
THIS SECTION
OF THE
MANUAL WITH
THIS PICTORIAL
WIRING DIAGRAM
ELEVATION
LIMIT
SWITCH
TO
BATTERY
TERMINAL
TO
BATTERY
CHARGER
CUTOUT
SWITCH
X105
X101
X104
FROM X101
CONNECTO
R
05
X1 R
M CT O
O
FR NNE
CO
PLATFORM
CONTROLLER
MC-1
CONTROLLER BOX
X103
GROUND
CONTROLS
SWITCH
BRAKE
RELEASE
WIRING
(LIFT UP/LIFT DOWN)
GROUND
CONTROLS
RELAY
EXTERNAL
DRIVE/HORN
RELAY
CONTACTOR
RELAY
BRAKE
RELEASE
WIRING
DRIVE MOTOR
POWER LEADS
MOTOR/BRAKE
ASSEMBLY
(LEFT SIDE)
DRIVE MOTOR
POWER LEADS
BRAKE LIMIT
SWITCH
WIRING
MOTOR/BRAKE
ASSEMBLY
(RIGHT SIDE)
Figure 3-4. Overview of VP UL-EE Approved Optional Electrical System. (Sheet 2 of 2)
3120728
– JLG Lift –
3-11
SECTION 3 - TROUBLESHOOTING
X101
B+
B+ CONTROL
MAIN POWER DISCONNECT
ELEVATION SWITCH
TILT CUTOUT
CHARGER INTERLOCK
B–
PIN
A1
3
5
1
2
4
A2
X102
B+
EMERGENCY STOP
CAN-LO
CAN-HI
CENTER DETECT
B–
EMERGENCY STOP
PIN
15
14
13
5
6
1
7
X103 – LEFT MOTOR
MOTOR 1
MOTOR 2
BRAKE 1
BRAKE2
PIN
A1
A2
5
3
PINS USED FOR
COMMUNICATION
TO SERIAL PORT
ON LAPTOP OR PC.
X104 – RIGHT MOTOR
MOTOR 1
MOTOR 2
BRAKE 1
BRAKE 2
X105
RX DO
TX DO
GROUND
LIFT UP
LIFT DOWN
PUMP CONTACTOR
DRIVE CUTOUT
BRAKE STATUS
HORN
ALARMS
HOURMETER
PIN
7
8
13
4
6
5
12
11
15
14
3
PIN
A1
A2
5
2
HORN
RELAY
X105
X101
X104
X102
X103
END VIEW OF MC-1 BOX
SHOWING X CONNECTOR LOCATION
Figure 3-5. VP Electrical Diagram. (with UL-EE Approved Option)
3-12
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
MOTION
ALARM
BREAKER
PUMP FUSE
PUMP VALVES
BREAKER
TILT BEAKER
BEACON BRKR.
POWER
RELAY
KEY SWITCH BREAKER
4933134_A
Figure 3-5 VP Electrical Diagram. (with UL-EE Approved Option)
3120728
– JLG Lift –
3-13
SECTION 3 - TROUBLESHOOTING
CYLINDER
PRES.
COMPENSATED
FLOW VALVE
RETURN TUBE
SOLENOID
WITH
MANUAL
OVERRIDE
EXTEND TUBE
FILTER/
SCREEN
FILTER/SCREEN
CHECK
VALVE
ADJ. RELIEF
VALVE
PUMP ENDHEAD
SOLENOID
TWO POSITION/TWO
WAY DUMP VALVE
PUMP
MOTOR
TANK
FILTER/SCREEN
1282953
Figure 3-6. Hydraulic Diagram. (VP Series)
3-14
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
3.5
TROUBLESHOOTING SECTION - TABLE OF CONTENTS
OHM RATINGS FOR VARIOUS COMPONENTS
PAGE
Ohm Ratings for Various Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
MAIN POWER CIRCUIT TROUBLESHOOTING
Unit Will Not Power Up From Ground Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
No Power At Platform Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
DRIVE TRAIN TROUBLESHOOTING
Won’t Drive (Platform Lowered Or Elevated) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20
Won’t Drive (Platform Elevated Only). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
Won’t Climb Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-24
Drives In Opposite Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-25
Will Only Drive A Short Distance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-26
Won’t Drive Straight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-28
Noise From Drive Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-29
MAST TROUBLESHOOTING
Platform Will Not Lift Up Using Platform Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-30
Platform Will Not Lower Using Platform Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33
Platform Will Not Lift Up From Ground Control Toggle Switch . . . . . . . . . . . . . . . . . . . . . . . . . 3-34
Platform Will Not Lower From Ground Control Toggle Switch . . . . . . . . . . . . . . . . . . . . . . . . . 3-35
Platform Will Not Lower Manually . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-36
Platform Lift Up And Down Jerky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-37
Mast Noisy When Lifting And Lowering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-38
Platform (Mast) Won’t Stay Elevated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-39
Platform (Mast) Descends Too Slowly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40
HYDRAULIC LEAK TROUBLESHOOTING
Miscellaneous Hydraulic Leak Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-41
BASE FRAME COMPONENTS TROUBLESHOOTING
Caster Wheels Not Operating Freely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-42
Pot Hole Protection (PHP) Bars Will Not Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-42
3120728
– JLG Lift –
3-15
SECTION 3 - TROUBLESHOOTING
3.6
OHM RATINGS FOR VARIOUS COMPONENTS
The following table contains ohm ratings for various VP Series machine components.
Table 3-3. Ohm Ratings for Various Components
COMPONENT
NOMINAL RESISTANCE @ TEMPERATURE
RESISTANCE RANGE POSSIBLE
46.8ohm - 57.2ohm @ 68deg F
35.7ohm - 67.3ohm
Pump Motor
0.2ohm - 0.4ohm @ 77deg F
0.12ohm - 0.49ohm
Pump Relay
16.0ohm - 17.6ohm @ 77deg F
9.9ohm - 21.8ohm
44.7ohm - 52ohm @ 68deg F
31.4ohm - 65.3ohm
.1 to .3ohm
(Can change depending on the rotation of the
armature and temperature.)
N/A
Main Contactor
Brake Coil
Drive Motor (Bodine)
3-16
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
3.7
MAIN POWER CIRCUIT TROUBLESHOOTING
Unit Will Not Power Up From Ground Control
Overview Of Procedure
The following procedure tests the circuits from the Battery (+) terminal through the Ground Control Box and to the Main
Contactor Relay and Main Contactor for 24 volts or more. Also the Lift Up/Down Relay circuit is tested.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Battery connections clean and tight.
• Key switch positioned to Ground (GRND) control.
• Emergency stop switch pulled out. (Reset Position)
Table 3-4. Unit will not Power Up From Ground Control.
STEP
ACTION
SPEC
YES
NO
Check the 5 amp inline fuse on the Red 1-1 wire from the battery (+)
terminal to the ground control box, key switch.
(Under pump/motor cover).
24 volts
OK, go to Step 2
Replace Fuse
24 volts
Go to Step 3
Check Wiring
from Battery to
Terminal B.
Repair or Replace
24 volts
Go to Step 4
Repair wiring or
Replace Key
Switch
Check for 24 volts or more on the Yel/Red, 2-8 wire from the E-stop
to the Ground Control Relay, terminal 86.
—
Go to Step 5
Repair wiring or
Replace E-Stop
Switch
Check for 24 volts or more on the Yel/Red, 2-4 wire from the E-stop
to the Main Contactor Relay, terminal 87.
—
Go to Step 6
Repair wiring or
Replace E-Stop
Switch
Check for 24 volts or more on the Yel/Red, 2-4 wire from the Main
Contactor Relay, terminal 87 to the Main Contactor.
—
Go to Step 7
Repair wiring or
Replace Main
Contactor Relay
7.
Did Main Contactor close?
—
Go to Step 9
Go to Step 8
8.
Is the Black ground wire connection from the Main Contactor to
ground OK?
—
Replace Main
Contactor
Repair Ground
Wiring
9.
At this point, 24 volts should be present at the following terminal
points; • Terminal 86 on the Ground Control Relay.
• Main Contactor, Yel/Red, 2-4 wire.
—
—
—
With Main Contactor engaged, 24 volts or more should be present at
the following terminal points;
• Pump Motor - 21’ cable #1.
• Yel/Red, 2-6 wire on the Pump Contactor.
• Yel/Red, 2-6 wires on the Lift Up/Down Relay.
—
—
—
1.
Ground Control Box Assembly (Disassembled)
2.
3.
4.
5.
Is there 24 volts or more reading at the key switch, terminal B.
Check for 24 volts or more on the Yel/Red, 2-7 wire from the key
switch to the E-stop switch.
Main Contactor Circuit
6.
10.
3120728
– JLG Lift –
3-17
SECTION 3 - TROUBLESHOOTING
No Power At Platform Control
Overview Of Procedure
The following procedure checks voltage and ground starting from the power source (batteries) through the ground control
station (key switch/E-stop) to the MC-1 box and finally to the platform control.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Keyswitch is turned to PLAT. (Platform)
• Both Emergency Stop Switches Reset (Ground/Platform). (Out)
• Connection of X102 Cable from MC-1 box to Platform Control, secure on both ends.
Table 3-5. No Power At Platform Control.
STEP
ACTION
1.
Check if the inline 5 amp fuse is blown on the Red, 1-1 wire at the
ground control station. (Ground control cover must be removed)
2.
Check voltage to the Yel/Red, 2-2 wire at the MC-1 box, X101 connector, pin 3.
3.
Check for Ground to the Black wire at the MC-1 box, X101 connector, pin A2.
SPEC
YES
NO
—
If OK, go to Step 2
Replace Fuse
Go to Step 3
Perform the EStop/Key Switch
Circuit Check
(Table 3-17)
Ground
Go to Step 4
Check connection/wiring
between Battery
and X101, Pin A2
24 volts
4.
Check voltage to the Yel/Red, 2-3 wire at the MC-1 box, X101 connector, pin 5.
24 volts
Go to Step 5
Replace MC-1
Control Box
5.
Check voltage to the Yel/Red, 2-5 wire at the MC-1 box, X101 connector, pin A1.
24 volts
Go to Step 13
Go to Step 6
6.
Check voltage to the Yel/Red, 2-2 wire at the MC-1 box, X101 connector, pin 3, from the Power Relay pin 30.
24 volts
Go to Step7
Check the wire
between the
Power Relay and
Connection
7.
Check voltage to the Power Relay, pin 87.
24 volts
Go to Step 9
Go to Step 8
8.
Check for Ground to the Power Relay on the Black wire pin 85, to
Ground.
Ground
Replace Relay
Check wiring to
Ground
Connection
Check voltage to the Yel/Red, 2-4 wire at the Main Contactor from
the Power Relay, pin 87.
24 volts
Go to Step 10
Check the Yel/
Red, 2-4 Wiring
Ground
Go to Step 11
Check wiring to
Ground
Connection
24 volts
Go to Step 12
Check Battery
Cable
24 volts
Check Yel/Red 25 Wire
Replace Main
Contactor
9.
10.
Check for Ground, on the Black wire to the Main Contactor.
11.
Check voltage at the Battery Cable from Battery to Main Contactor.
12.
Check voltage to the Yel/Red, 2-5 wire at the Main Contactor.
3-18
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-5. No Power At Platform Control.
13.
Check voltage on the Red/Blk wire at the MC-1 box, X102 connector, pin 15, to the Platform Control.
24 volts
Go to Step 14
Replace MC-1
Box
14.
Check for Ground on the BRN wire at the MC-1 box, X102 connector,
pin 1, to the Platform Control.
Ground
Go to Step 15
Replace MC-1
Box
15.
Check voltage on the Red/Blk wire, pin 9 on the Platform Control
box.
24 volts
Go to Step 16
Replace Cable
16.
Check for Ground on the BRN wire, pin 8 on the Platform Control
box.
Ground
Replace Platform
Control
Replace Cable
3120728
– JLG Lift –
3-19
SECTION 3 - TROUBLESHOOTING
3.8
DRIVE TRAIN TROUBLESHOOTING
Won’t Drive (Platform Lowered Or Elevated)
IF MACHINE WON’T DRIVE ONLY WHEN PLATFORM IS ELEVATED, SEE SECTION 4.4
Overview Of Procedure
The following procedures check the components and circuits that feed data to the MC-1 Controller box assuring it is receiving the proper signals and conditions before engaging the machines’ drive motors.
Check For These Obvious Conditions First:
• Joystick Powered On
• Unit will Lift & Lower Platform
• Machine is not Tilted - (3 LEDs flashing at joystick control)
• PHP Device is not Obstructed - (4 LEDs flashing at joystick control)
• Brakes are not Released - (2 LEDs flashing at joystick control)
• Charger is not Plugged In - (8 LEDs flashing at joystick control)
Table 3-6. Won’t Drive. (Platform Lowered or Elevated)
STEP
1.
2.
3.
4.
ACTION
SPEC
YES
NO
Check for ground from elevation limit switch in the X101 connector,
pin 1 (49-5) at MC-1 box.
—
Go to Step 2
Check Elevation
Limit Switch
Circuit (Table 3-7)
—
Faulty Charger
Go to Step 3
Check for ground from brake limit switches in the X105 connector,
pin 11 at MC-1 box.
—
Go to Step 4
Check Brake
Limit Switch Circuit (Table 3-8)
Check that brakes are releasing, (2 LEDs) when joystick is enabled
& moved forward.
—
Check Drive
Motor Circuit
(Table 3-9)
Check Brake
Switch/Circuit
(Table 3-10)
SPEC
YES
NO
—
Go to Step 2
Repair
Connection
—
Go to Step 3
Adjust/Replace
Switch
—
—
Repair Wire or
Connection
Check for ground from charger circuit wire in the X101 connector,
pin 4 (49-7) at MC-1 box. (Perform this check with the charger
unplugged)
Table 3-7. Elevation Switch Circuit Check
• Perform these checks at the elevation switch which is located inside the top of mast section-1.
• Check with mast lowered.
STEP
ACTION
1.
Check for ground into the switch from ground connection.
2.
Check for ground out of switch to the 49-5 wire.
3.
Check for ground from switch to X101, Pin 1.
3-20
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-8. Brake Limit Switch Circuit Check
STEP
ACTION
SPEC
YES
NO
—
Go to Step 2
Repair
Connection
Check for ground on the 49-4 wire coming out of left brake limit
switch.
—
Go to Step 3
Adjust/Replace
Switch
3.
Check for ground on the 49-4 wire going into the right brake limit
switch.
—
Go to Step 4
Repair/Replace
49-4 wire
4.
Check for gound on the 49-3 side of the right brake limit switch.
—
Replace
MC-1 box
Repair wire or
Connection
1.
Check for ground into the switch from the ground connection on the
left brake limit switch.
2.
Table 3-9. Drive Motor/Circuit Check
• Perform these checks with the joystick enabled and pushed to the full forward position.
STEP
SPEC
YES
NO
1.
Check for 24 volts at the drive motor on the 55-3 wire on the right
motor and the 55-7 wire on the left drive motor. (Positive Side)
ACTION
24 volts
Problem with
Motor
Go the Step 2
2.
Check for 24 volts at the 55-3 wire at the X104 connector, pin A2 (for
right motor) and the 55-7 wire at the X103 connector, pin A1 (for left
motor).
24 volts
Check wiring and Problem in MC-1
connections
box or Joystick
Table 3-10. Brake Switch/Circuit Check
• Perform these checks with the joystick enabled and pushed to the full forward position.
STEP
1.
2.
3120728
ACTION
SPEC
YES
NO
Check for 24 volts at the wiring connectors on the 55-4 wire on the
right drive motor brake unit and the 55-8 wire on the left drive motor
brake unit.
24 volts
Clean, Gap or
Replace Brake
Unit
Go to Step 2
Check for 24 volts at the 55-4 wire at the X104 connector, pin 5(for
right motor) and the 55-8 wire at the X103 connector, pin 5 (for left
motor).
24 volts
– JLG Lift –
Check wiring and Problem in MC-1
connections
box or Joystick
3-21
SECTION 3 - TROUBLESHOOTING
Won’t Drive (Platform Elevated Only)
Overview Of Procedure
The following procedures check the components and circuits that feed data to the MC-1 Controller box assuring it is receiving the proper signals and conditions before engaging the machines’ drive motors.
Check For These Obvious Conditions First:
• Joystick Powered On
• Unit will Lift & Lower Platform
• Machine is not Tilted - (3 LEDs flashing at joystick control)
• PHP Device is not Obstructed - (4 LEDs flashing at joystick control)
• Brakes are not Released - (2 LEDs flashing at joystick control)
• Charger is not Plugged In - (8 LEDs flashing at joystick control)
Table 3-11. Won’t Drive with Platform Elevated
STEP
1.
2.
ACTION
SPEC
YES
NO
Check for ground on tilt circuit at MC-1 box, X101 connector, pin 2,
(O/R, 49-6 wire).
—
Go to Step 2
Check Tilt Sensor
Circuit (Table 312)
Check for ground on PHP circuit at MC-1 box, X105 connector, pin
12, (O/R, 49-1 wire).
—
Problem in MC-1
controller box
Check PHP
Switch Circuit
(Table 3-13)
Table 3-12. Tilt Sensor Circuit Check
• No ground at MC-1 box, X101 connector, pin 2, (O/R, 49-6 wire).
STEP
ACTION
SPEC
YES
NO
1.
Is tilt sensor light on showing a tilt condition, even though machine is
within tilt limit.
—
Adjust tilt sensor
if necessary
Go to Step 2
2.
Check for ground on the Black wire (direct to ground) running into tilt
sensor. (Continuity to B-)
—
Go to Step 3
Repair
Connection
3.
Check for 24 volts at the Green to (Y/R, 2-5) wire from the main contactor relay.
—
Go to Step 4
Check Connection to Main Contactor Relay
—
Repair connection at the X101
connector end/
broken wire O/R
49-6
Replace
Tilt Sensor
4.
3-22
Check for ground on the White to (O/R, 49-6) wire at connector.
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-13. PHP Limit Switch Circuit
• No ground on PHP circuit at MC-1 box, X105 connector, pin 12, (O/R, 49-1 wire).
• With PHP bars up.
STEP
ACTION
1.
Check for ground on Black wire (direct to ground) on the right side
PHP limit switch. (Continuity to B –)
2.
Check for ground on O/R, 49-2 wire to left PHP limit switch.
3.
Check for ground on O/R, 49-1 wire to MC-1 box, X105 connector,
pin 12.
3120728
– JLG Lift –
SPEC
YES
NO
—
Go to Step 2
Repair
Connection
—
Go to Step 3
Adjust/Replace
Right Switch
—
Repair connection at the X105
connector end
Adjust/Replace
Left Switch
3-23
SECTION 3 - TROUBLESHOOTING
Won’t Climb Grade
Overview Of Procedure
The following procedure checks the drive motor and attached components for component failure, misadjustment due to
wear.
Check For These Obvious Conditions First:
• Batteries are Fully Charged (24 Volts)
• Speed Control is Set to Maximum
• Is Grade within the Maximum Allowable Specification of 15% Grade (8.5 degrees)
• Does the Travel Surface allow for Proper Drive Wheel Traction
• Is Platform Load within the Maximum Rated Capacity
Table 3-14. Won’t Climb Grade
STEP
1.
2.
3.
4.
5.
6.
3-24
ACTION
SPEC
YES
NO
—
Go to Step 2
Refer to Machine
Won’t Drive
Straight
(Table 3-18)
Are both the left and right drive motor, slip-clutches, located
between the drive motor and the drive wheels, working properly?
—
Go to Step 3
Repair, Replace
or Adjust Slip
Clutch
Do the left and right drive motor brakes release properly and allow
the drive wheels to rotate freely ?
—
Go to Step 4
Dragging?
Repair, Replace
or Adjust Brakes
—
Controller will
Shut Drive Down
and will flash a 7
LED Code
Go to Step 5
—
OK, go to Step 6
Worn down,
replace brushes
or drive motor
—
—
—
Does machine drive straight on a level surface?
Check the amperage output of the on the drive motor leads. They
should not exceed 70 amps while pulling a grade.
Check the condition of the drive motor brushes.
If all above is OK, Drive motors are working properly. Consult Factory.
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Drives In Opposite Direction
Overview Of Procedure
The following procedure checks that both the drive motor power wire connections correctly installed and are secure and
tight. Also that the joystick control assembly for proper installation at the platform control box.
Check For These Obvious Conditions First:
• If the Left Drive Motor (X103) connector is switched with the Right Drive Motor (X104) connector at the MC-1 box, you will
immediately get an 2 LED flashing Error Code at the Platform Control when the machine is powered up.
• Check Joystick Calibration (See Procedure in Service Manual, Section-2).
Table 3-15. Drives In Opposite Direction
STEP
SPEC
YES
NO
Check the connection of the Orange, 55-3 wire to the right drive
motor at both ends;
• At the X104 connector on the MC-1 box, pin A1.
• And the Black wire at the Drive Motor end.
—
Go to Step 2
* Repair or
Replace
Connection
Check the connection of the Orange, 55-6 wire to the right drive
motor at both ends;
• At the X104 connector on the MC-1 box, pin A2.
• And the White wire at the Drive Motor end.
—
Go to Step 3
* Repair or
Replace
Connection
Check the connection of the Orange, 55-7 wire to the left drive motor
at both ends;
• At the X103 connector on the MC-1 box, pin A1.
• And the Black wire at the Drive Motor end.
—
Go to Step 4
* Repair or
Replace
Connection
Check the connection of the Orange, 55-10 wire to the left drive
motor at both ends;
• At the X103 connector on the MC-1 box, pin A2.
• And the White wire at the Drive Motor end.
—
Go to Step 5
* Repair or
Replace
Connection
5.
Is platform control box under warranty? **
—
Order New One
Go to Step 6
6.
Internal to the platform control - check that the joystick assembly
inside the platform control has not been installed backwards.
—
Re-install
Correctly
Go to Step 7
7.
Internal to the platform control - check that the joystick assembly
wiring to the platform control circuit card is not wired backwards.
—
Re-install
Correctly
Consult Factory
1.
2.
3.
4.
ACTION
* Note: If the Orange, 55-3 or 55-6 wires to the right drive motor in the X104 connector or the Orange, 55-7 or 55-10 wires to
the left drive motor in the X103 connector at the MC-1 controller are crossed up that drive motor will run backwards.
** Note: If platform controller is not under warranty, the internal components of the platform controller are replaceable and
can be ordered and replaced seperately from the complete platform control box. See procedures in Section-2 of
this Service Manual for Joystick Assembly/ Disassembly.
3120728
– JLG Lift –
3-25
SECTION 3 - TROUBLESHOOTING
Will Only Drive A Short Distance
Overview Of Procedure
The following procedure will eliminate any problems found in the power circuit to the MC-1 controller box and also any
objectionable environmental conditions.
Check For These Obvious Conditions First:
• Is Battery Voltage 24 Volts? (Fully Charge Batteries)
Table 3-16. Only Drives A Short Distance
STEP
1.
2.
ACTION
SPEC
Is platform controller staying powered up when machine stops driving?
Check the voltage out of the X101 connector, pin 5, to the power
relay pin 86. Check continuity at pin 85.
3.
Check the voltage from pin 87 on the power relay to the main contactor. (Main contactor should be closed at this point)
4.
Check the voltage on the Yel/Red, 2-5 wire on the X101 connector,
pin A1, from the main contactor.
5.
6.
YES
NO
—
Go to Step 2
Check the E-Stop
& Key Switch
Circuit
(Table 3-17)
24 Volts
Go to Step 3
Repair or Replace
Wires, or Problem
with MC-1 Box
24 Volts
Go to Step 4
Repair or Replace
Wires or Relay
24 Volts
Go to Step 5
Repair or Replace
Wires or Main
Contactor
—
Machine will not
perform well on a
soft or unstable
surface, if motor
draw is over 70
amps, controller
will shut the
machine down.
( 7 LED Code)
Go to Step 6
Go to Step 7
Repair/Replace
or Adjust Drive
Brakes
(See Procedure in
Service Manual)
—
Go to Step 8
Repair/Replace
or Adjust Drive
System
(See Procedure in
Service Manual)
—
Machine may be
building static
charge in the MC1 controller,
which will make
the drive system
shut down.
—
What type of surface is machine being operated on? Is surface soft,
unstable or up a steep grade?
Are brakes releasing when trying to drive?
—
7.
8.
3-26
Is drive system running free? No noise or dragging.
Is machine being operated in an environment with high static
charge?
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-17. E-Stop and Key Switch Circuit Check
• Batteries Fully Charged. (24 Volts)
• Ground Control Key Switch set to the Platform or on Ground position and the Emergency Stop Switch Reset to ON.
STEP
1.
2.
3.
4.
5.
6.
3120728
ACTION
SPEC
YES
NO
KEY SET TO PLATFORM: Check voltage on the Yel/Red, 2-2 wire
from the emergency stop switch to MC-1 controller box, pin 3 in the
X101 connector and pin 30 on the Power Relay.
24 Volts
Circuit is OK
Go to Step 2
KEY SET TO GROUND: Check voltage on the Yel/Red, 2-4 wire coming out of the ground control box assembly to pin 87 on the power
relay, and main contactor. Yel/Red 2-8 wire to pin 86 on the ground
relay.
24 Volts
Circuit is OK
Go to Step 3
Open the Ground Control Box Assembly (housing with key switch
and E-stop switch mounted inside) and check the voltage on the Yel/
Red, 2-1 wire leading into the emergency stop switch from the Key
switch.
24 Volts
Repair connection to or replace
E-Stop switch
Go to Step 3
24 Volts
Repair connection to or replace
key switch
Go to Step 4
Check voltage and continuity through the 5 amp fuse mounted inline
outside of the ground control box assembly, on the Red, 1-1 wire.
24 Volts
Go to Step 6
Replace Fuse or
Fuse Holder if
damaged
Check connection at battery.
24 Volts
Circuit OK
N/A
Check voltage on the Red, 1-1 wire leading into the Key switch.
– JLG Lift –
3-27
SECTION 3 - TROUBLESHOOTING
Won’t Drive Straight
Overview Of Procedure
The following procedure examines the drive motor assembly weldments attaching the drive motors to the base frame. Also
internal components of the the drive motors, gear box and a check of the components between the gear box and the drive
wheels.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Nothing is lodged between one of the wheels and the base frame.
• A caster wheel on the front of the machine is seized up, creating resistance.
• Joystick properly calibrated per procedure in Section-2 of Service Manual.
Table 3-18. Won’t Drive Straight.
STEP
ACTION
SPEC
YES
NO
1.
Check for the following on the drive assembly, drive attachment
weldment; is bent, has broken welds, or loose hardware.
—
Repair/Replace/
Tighten weldment
Go to Step 2
2.
Check for the following on the drive assembly, drive motor mounting
plates; are bent, are square with drive weldments, or is hardware
loose?
—
Repair/Replace/
Tighten weldment
Go to Step 3
Check for the following on the drive assembly, drive motor hardware; is hardware loose, flange bearing - bad/loose, slip clutch check torque settings or adjustment.
—
Repair/Replace/
Tighten component
Go to Step 4
—
Tighten or Adjust
per procedure
in this
Service Manual
Go to Step 5
—
Repair/Replace
components per
procedure in this
Service Manual
Go to Step 6
24 volts
15 amps
Recheck Steps
1 thru 5
Go to Step 7
—
Replace per
procedure in this
Service Manual
Go to Step 8
Is the X102 wiring harness (from platform contol box to MC-1 box)
damaged, check wiring harness visually and individual wires with
ohm meter.
—
Repair or Replace
Harness as
Required
Go to Step 9
Is joystick control defective?
If possible, swap out with another platform control.
—
Repair/Replace
Platform control
Go to Step 10
—
Tighten Connections or Replace
MC-1 box
—
3.
4.
5.
Check the left and right drive motor brakes for loose hardware & not
releasing properly.
Inside the drive motor gear box check if; the drive shaft is excessively loose & conditon of drive shaft bearings.
Are any gears broken or gear teeth excessively worn.
6.
Is the electrical signal and amperage draw to the drive motors
equal?
7.
Check the drive motor brushes, do they need replaced?
8.
9.
10.
3-28
Is MC-1 control box defective or connections not tight?
If possible, swap out with another MC-1 control box.
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Noise From Drive Assembly
Overview Of Procedure
The following procedure examines the drive motor assembly weldments attaching the drive motors to the base frame. Also
internal components of the the drive motors, gear box and a check of the components between the gear box and the drive
wheels.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Nothing is lodged between one of the wheels and the base frame.
• A caster wheel on the front of the machine is seized up, creating resistance.
Table 3-19. Noise from Drive Assembly.
STEP
ACTION
SPEC
YES
NO
1.
Check for the following on the drive assembly, drive attachment
weldment; is bent, has broken welds, or loose hardware.
—
Repair/Replace/
Tighten weldment
Go to Step 2
2.
Check for the following on the drive assembly, drive motor mounting
plates; are bent, are square with drive weldments, or is hardware
loose?
—
Repair/Replace/
Tighten weldment
Go to Step 3
Check for the following on the drive assembly, drive motor hardware; is hardware loose, flange bearing - bad/loose, slip clutch check torque settings or adjustment.
—
Repair/Replace/
Tighten
Component
Go to Step 4
—
Tighten or Adjust
per procedure
in this
Service Manual
Go to Step 5
—
Repair/Replace
components per
procedure in this
Service Manual
Go to Step 6
24 volts
15 amps
Recheck Steps
1 thru 5
Go to Step 7
—
Replace per
procedure in this
Service Manual
—
3.
4.
5.
Check the left and right drive motor brakes for loose hardware & not
releasing properly.
Inside the drive motor gear box check if; the drive shaft is excessively loose & conditon of drive shaft bearings.
Are any gears broken or gear teeth excessively worn.
6.
Is the electrical signal and amperage draw to the drive motors
equal?
7.
Check the drive motor brushes, do they need replaced?
3120728
– JLG Lift –
3-29
SECTION 3 - TROUBLESHOOTING
3.9
MAST TROUBLESHOOTING
Platform Will Not Lift Up Using Platform Control
Overview Of Procedure
This procedure examines the complete pump motor, ground control and pump valves electrical circuits.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Platform loaded within maximum allowable capacity.
• Hydraulic oil is within it’s specified operating temperature range.
Table 3-20. Platform Will Not Lift Up Using Platform Control.
STEP
ACTION
1.
Will platform lift from ground control switch?
Note: Key switch must be set to GRND to test this.
2.
Does pump motor run?
3.
4.
Are the down and dump valves opening/closing properly?
Note: If machine will not lift and hydraulic oil is visible flowing in the
hydraulic tank, the dump valve is stuck in the open position.
YES
NO
—
Go to Step 2
See (Figure 3-24)
—
Go to Step 3
See Pump Circuit
Check
(Table 3-21 )
—
Go to Step 4
See Pump Valves
Circuit Check
(Table 3-22 )
—
Go to Step 5
Set to correct
pressure specification per this
Service Manual
—
Go to Step 6
Rebuild or
Replace Lift Cyl.
—
Consult
Factory
Check Mast,
Rebuild
if Necessary
Is the pressure set properly on the pump?
5.
Is the lift cylinder OK?
6.
Are the mast sections operating freely?
3-30
SPEC
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Table 3-21. Pump Circuit
• Battery voltage 24 volts. (Fully charge batteries)
• Key switch set to Platform .
STEP
1.
ACTION
SPEC
At the pump motor, check for 24 volts at both ends of the battery
cable running from the main contactor to the pump case stud. (left
side)
YES
NO
Go to Step 2
Tighten
Connection or
Replace Cable
if Necessary
Go to Step 3
Tighten
Connection or
Replace Cable
if Necessary
Ground
Go to Step 4
Tighten
Connection or
Replace Cable
if Necessary
24 volts
PUMP CONTACTOR RELAY CIRCUIT
2.
3.
Check the connection of the ground cable (attached to 5/16" stud,
left side) to the pump contactor, is tight and connected on other end
to B- at the right side battery.
Check the connection of the ground cable (other side) is tight and
connected to the pump case stud (center).
Ground
4.
Check the Yel/Red, 2-6 wire connected to the positive post on the
pump case for tightness and 24 volt reading.
24 volts
Go to Step 5
Tighten/Repair
Connection
5.
Check the Tan, 55-1 wire connected to both the Ground control
switch and the MC-1 box, X105 connector, pin 5 through the pump
contactor relay. Without any lift functions activated, it should show
24 volts, with a lift function activated it should show ground.
Ground
Go to Step 6
Tighten/Repair
Connection
DUMP VALVE CIRCUIT
6.
Check the Yel/Red, 2-6 wire connected to the positive (+) post on
the pump case for 24 volts.
24 volts
Go to Step 7
Tighten/Repair
Connection
7.
Check the Tan, 3-1 wire connected to both the Ground control
switch and the MC-1 box, X105 connector, pin 4 through the lift up
valve. Without any lift function activated, it should show 24 volts,
with a lift function activated it should show ground.
24 volts
Go to Step 8
Tighten/Repair
Connection
DOWN VALVE CIRCUIT
8.
Check the Yel/Red, 2-6 wire connected to the positive (+) post on
the pump case for 24 volts.
24 volts
Go to Step 9
Tighten/Repair
Connection
9.
Check the Tan, 4-1 wire connected to both the Ground control
switch and the MC-1 box, X105 connector, pin 6 through the lift
down valve. Without any lift functions, it should show 24 volts, with
a lift function it should show ground.
24 volts
Go to Step 10
Tighten/Repair
Connection
24 volts
Go to Step 11
Tighten/Repair
Connection
MAIN CONTACTOR CIRCUIT
10.
Check the battery cable from the B+ (left side) battery for 24 volts.
11.
Check the battery cable going out to the pump case (left side) stud
for 24 volts.
24 volts
Go to Step 12
Tighten/Repair
Connection
12.
Check the Yel/Red, 2-5 (10 ga.) wire to the MC-1 box, X101 connector, pin A1 for 24 volts.
24 volts
Go to Step 13
Tighten/Repair
Connection
13.
Check the Yel/Red, 2-4 wire to the Power Relay, pin #87 for 24
volts.
24 volts
Go to Step 14
Tighten/Repair
Connection
3120728
– JLG Lift –
3-31
SECTION 3 - TROUBLESHOOTING
Table 3-21. Pump Circuit
Ground
Go to Step 15
Tighten/Repair
Connection
Check the Yel/Red, 2-4 wire, #87 on the Power Relay to the main
contactor, and to diode at E-Stop for 24 volts.
Note: Power will stop at diode, silver line should be away from the EStop.
24 volts
Go to Step 16
Tighten/Repair
Connection
16.
Check the Yel/Red, 2-2 wire, #30 on the Power Relay to the E-stop
and to the MC-1 box, X101 connector pin 3, for 24 volts.
24 volts
Go to Step 17
Tighten/Repair
Connection
17.
Check the Black, #85 pin on the Power Relay for connection to
ground at pump contactor.
Ground
Go to Step
Tighten/Repair
Connection
18.
Check the Yel/Red, 2-3 wire, #86 on the Power Relay to the MC-1
box, X101 connector pin 5, for 24 volts when the platform control is
powered up.
—
Go to Step
Tighten/Repair
Connection
14.
Check the Black to ground on the pump contactor.
POWER RELAY CIRCUIT
15.
Table 3-22. Pump Valves Circuit
• Battery voltage 24 volts. (Fully charge batteries)
• Set key switch to Platform and set the Emergency Stop Button to the RESET position.
• Down Valve should be normal (closed).
• Dump Valve (up) should be normal (open).
• If machine will not lift and hydraulic oil is visible flowing in the hydraulic tank, the dump valve is stuck open.
STEP
ACTION
SPEC
YES
NO
—
—
—
—
—
—
—
—
—
—
—
—
LIFT UP - (CONDITIONS WHEN PUMP MOTOR IS RUNNING)
1.
Pump Contactor Coil:
Yel/Red, 2-6 wire - 24 volts
Tan, 55-1 wire - Ground
2.
Lift Up Valve Coil: Yel/Red, 2-6 wire - 24 volts
Tan, 3-1 wire - Ground
LIFT UP - (CHECK WHEN PUMP MOTOR IS NOT RUNNING)
3.
Pump Contactor Coil:
Yel/Red, 2-6 wire - 24 volts
Tan, 55-1 wire - 24 volts
4.
Lift Up Valve Coil: Yel/Red, 2-6 wire - 24 volts
Tan, 3-1 wire - 24 volts
LIFT DOWN - (CHECK WHEN DOWN AND ENABLE PADS ARE PUSHED ON THE PLATFORM CONTROL)
5.
Lift Down Valve Coil:Yel/Red, 2-6 wire - 24 volts
Tan, 4-1 wire - Ground
—
—
—
—
—
LIFT DOWN - (CHECK WHEN NO FUNCTION ARE ENABLED ON THE PLATFORM CONTROL)
6.
3-32
Lift Down Valve Coil:Yel/Red, 2-6 wire - 24 volts
Tan, 4-1 wire - 24 volts
—
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Platform Will Not Lower Using Platform Control
Overview Of Procedure
This procedure tests for ground coming out of the MC-1 box to the dump valve circuit and through to the ground control toggle switch.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Hydraulic oil is within it’s specified operating temperature range.
Table 3-23. Platform Will Not Lower Using Platform Control.
STEP
ACTION
SPEC
YES
NO
1.
Will machine lower manually, using the manual descent knob?
—
Go to Step 2
See (Table 3-26)
2.
Will machine lower from ground control switch?
Note: Key switch must be set to GRND to check this.
—
Go to Step 3
See (Table 3-23)
3.
Check for ground on the Tan, 4-1 wire at the MC-1 box, X105 connector, pin 6.
—
Go to Step 4
Repair/Replace
Joystick/
MC-1 Box
—
Go to Step 5
Replace/Repair
Wire or
Connection
—
—
—
4.
5.
3120728
Check for ground on the Tan, 4-1 wire at the lift down coil.
Check complete pump motor circuit . (See Table 3-21)
– JLG Lift –
3-33
SECTION 3 - TROUBLESHOOTING
Platform Will Not Lift Up From Ground Control Toggle Switch
Overview Of Procedure
The following procedure examines the complete ground control circuit from the battery all the way to the pump motor for
wiring or components which could be causing a failure of that circuit.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Battery connections clean and tight.
• Key switch positioned to Ground (GRND) control.
• Emergency stop switch pulled out. (Reset Position)
• Ground control power supply and wiring, OK (Table 3-4).
• Manual descent valve closed.
• 5 amp fuses on power and pump circuits, OK.
• Hydraulic oil level, OK.
• Weight in platform does not exceed machine maximum capacity.
Table 3-24. Unit Will Not Lift Up From Ground Control Toggle Switch.
STEP
1.
ACTION
SPEC
YES
NO
—
Go to Steps 5,6
and 10
Check Ground
Power Circuit
(Table 3-4)
Before Continuing to Step 3
Does the pump motor run when lift up is selected at the ground control switch?
Note: Steps 2 thru 9 are to be performed with LIFT UP selected at the
ground control.
2.
Check terminal 30 and 85 on the ground control relay for ground. Is
ground contact OK?
Ground
Go to Step 3
Repair Wiring or
Connection
3.
Check continuity across terminals 87 and 30 on the ground control
relay. Is there continuity? (Relay must be energized)
—
Go to Step 4
Replace Relay
4.
Check the Black wire from terminal 87 on the ground control relay to
the lift up/down ground control switch. Is there continuity with B –?
—
Go to Step 5
Repair Wiring or
Connection
5.
Check for continuity across the terminals (Black to Tan 3-1 and Tan
55-1) of the lift up/down ground control toggle switch. Is there continuity?
—
Go to Step 6
Replace Lift Up/
Down Ground
Control Switch
6.
Check the Tan, 3-1 wire for continuity from the lift up/down ground
switch to the lift up coil. Is there continuity?
—
Go to Step 7
Repair Wiring or
Connection
7.
Check the Tan, 55-1 wire from the lift up/down ground switch to the
pump contactor for continuity. Is there continuity?
—
Go to Step 8
Repair Wiring or
Connection
8.
Check the Yel/Red, 2-6 wire from the pump motor to the pump contactor and lift-up coil for voltage. Is there voltage?
24 Volts
Go to Step 9
Repair Wiring or
Connection
9.
Check the wire from the lift switch (Tan 55-1) pump contactor to the
battery (-) terminal for continuity. Is there continuity?
—
—
Repair Wiring or
Connection
10.
Check the pump motor pressure relief setting. Is it within specification per Service Manual?
—
3-34
– JLG Lift –
Set as Required
3120728
SECTION 3 - TROUBLESHOOTING
Platform Will Not Lower From Ground Control Toggle Switch
Overview Of Procedure
The following procedure examines the complete ground control circuit from the battery all the way to the pump motor for
wiring or components which could be causing a failure of that circuit.
Check For These Obvious Conditions First:
• Battery voltage 24 volts. (Fully charge batteries)
• Battery connections clean and tight.
• Key switch positioned to Ground (GRND) control.
• Emergency stop switch set to the Reset position)
• Ground control power supply and wiring, OK (Table 3-4).
• 5 amp fuses on power and pump circuits, OK.
• Hydraulic oil level, OK.
Table 3-25. Unit Will Not Lower From Ground Control Toggle Switch.
STEP
ACTION
SPEC
YES
NO
1.
Will machine lower manually?
—
Go to Step 3
Go to Step 2
2.
Check for obstructions in the mast, cylinder, hydraulic lines and lift
down valve.
—
Repair, Replace
or Adjust
Go to Step 3
3.
Check terminal 30 and 85 on the ground control relay for ground. Is
ground contact OK? Continuity with B–.
Ground
Go to Step 4
Repair Wiring or
Connection
4.
Check continuity across terminals 87 and 30 on the ground control
relay. Is there continuity? (Relay must be energized)
Ground
Go to Step 5
Replace Relay
5.
Check the Black wire from terminal 87 on the ground control relay to
the lift up/down ground control switch. Is there continuity with B –?
—
Go to Step 6
Repair Wiring or
Connection
6.
Check for continuity across the terminals (Black to Tan, 4-1 wire) of
the lift up/down ground control toggle switch. Is there continuity
with the switch activated?
—
Go to Step 7
Replace Lift Up/
Down Ground
Control Switch
7.
Check the Tan, 4-1 wire for continuity from the lift up/down ground
switch to the lift-down coil. Is there continuity?
—
Go to Step 7
Repair Wiring or
Connection
8.
Check the Yel/Red, 2-6 wire from the pump motor to the lift-down
coil for voltage. Is there voltage?
24 volts
—
Repair Wiring or
Connection
3120728
– JLG Lift –
3-35
SECTION 3 - TROUBLESHOOTING
Platform Will Not Lower Manually
Overview Of Procedure
The following procedure suggests components on the machine which might attribute to problems with the manual descent
circuit.
Table 3-26. Platform Will Not Lower Manually.
STEP
ACTION
SPEC
1.
Check manual override solenoid with manual override (knob open).
2.
Check Steps 1 thru 6 of ( Table 3-30)
3.
Place the maximum capacity of weight in the Platform.
Does it Lower?
3-36
– JLG Lift –
YES
NO
Go to Step 2
Open
Repair
Go to Step 3
—
Consult Factory
3120728
SECTION 3 - TROUBLESHOOTING
Platform Lift Up And Down Jerky
Overview Of Procedure
The following procedure suggests areas on the machine which might attribute to erratic movement of the platform during lift
up and down.
Check For These Obvious Conditions First:
• If mast is not running smooth or has tight and rough spots, refer to the Mast Section Rebuild.
• Hydraulic oil level in reservoir tank at full level.
• Hydraulic oil no milky (presence of water), or not foamy (full of air).
Table 3-27. Platform Lift Up and Down Jerky.
STEP
ACTION
SPEC
YES
NO
—
Replace pad
Go to Step 2
—
Repair
connection
Go to Step 3
—
Repair Connection or Replace
Valve
Go to Step 4
—
Replace box
Go to Step 5
CONTROLS (ELECTRICAL)
1.
Is platform control, enable, up or down pad defective or worn out?
2.
Loose connections , ground and power.
3.
Valve coils or solenoids keep opening and closing.
4.
Problem internal to the MC-1 control box.
HYDRAULIC
5.
Are the hydraulic valves working properly.
—
Replace Valve
Go to Step 6
6.
Pump drive cavitates.
—
Replace Pump
Go to Step 7
7.
Lift cylinder
—
Rebuild or
Replace Cylinder
—
3120728
– JLG Lift –
3-37
SECTION 3 - TROUBLESHOOTING
Mast Noisy When Lifting And Lowering
Overview Of Procedure
This procedure examines components of the mast itself and as well as it’s lifting components for dirt, debris, proper lubrication and operation.
Table 3-28. Mast Noisy when Lifting and Lowering.
STEP
ACTION
SPEC
YES
NO
1.
Do slide pads and slide pad channels need to be cleaned of dust,
dirt, or other debris?
—
Clean Pads and
Channels
Go to Step 2
2.
Do chain/cables need to be lubricated per JLG specification in the
Service Manual?
—
Lubricate as
Required
Go to Step 3
3.
Are the chain/cable sheave wheels dry and need lubrication?
Note: Plastic wheels will howl on the sheave pin when they are dry.
Sheave wheels may seize to the sheave pin and the pin may turn in
the pin retainer blocks.
—
Lubricate or
Replace Sheave
Pins and Wheels
Go to Step 4
—
Clean Slide Pads/
Channels or Reshim Mast per
Service Manual
Go to Step 5
—
Replace Packing
or Lift Cylinder
Go to Step 6
—
Repair or Replace
Pump
Go to Step 7
—
Adjust the Position of the Lines
Go to Step 8
—
Tighten pump
mounting
fasteners
Go to Step 9
—
Repair or Replace
Pump
—
4.
Are the sequence cables (located on the side of mast) chattering
when the springs are compressed?
Note: This noise is normal at the sequence cable sheave wheels
when the mast is completely lowered. However if the sequence
cable chattering is happening no matter what position the mast is in,
it could be a result of the mast being shimmed to tight or dirt and
debris in the slide pad channels causing the mast to be tight.
5.
Is the bore of the lift cylinder dry?
6.
Are the bearings in the lift pump motor and pump drive worn?
7.
Are the hydraulic lines vibrating together?
8.
Check if the pump motor is loose to it’s mounting plate.
9.
3-38
Hydraulic oil could be cavatating inside the pump.
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
Platform (Mast) Won’t Stay Elevated
Overview Of Procedure
The following procedure requests that the lift down, dump, and pump internal valves be checked to see if any are stuck
open, it also examines the lift down and dump valve circuits. Also suggests that the lift cylinder packing could be leaking
internally.
Check For These Obvious Conditions First:
• Manual descent valve is closed tight.
Table 3-29. Platform (Mast) Won’t Stay Elevated.
STEP
ACTION
1.
Is the lift down valve stuck open?
2.
Check the valve inside the pump, it could be stuck open.
3.
Lift down valves could be open due to incorrect electrical signal.
4.
5.
3120728
SPEC
YES
NO
—
Repair or Clean
Valve
Go to Step 2
—
Replace Pump
Go to Step 3
—
Check Pump
Valve Electrical
Circuit
(Table 3-22)
Go to Step 4
—
Check Pump
Valve Electrical
Circuit
(Table 3-22)
Go to Step 5
—
Replace or
Rebuild the Lift
Cylinder
—
Dump valve could be open due to incorrect electrical signal.
Oil could be passing around the lift cylinder bore packing.
– JLG Lift –
3-39
SECTION 3 - TROUBLESHOOTING
Platform (Mast) Descends Too Slowly
Overview Of Procedure
The following procedure examines the mast some hydraulic components for obstructions and defects.
Table 3-30. Platform (Mast) Descends Too Slowly.
STEP
ACTION
SPEC
YES
NO
—
Reshim Mast
Go to Step 2
—
Remove
Obstruction
Go to Step 3
1.
Check mast slide pads shimmed to tight.
2.
Is there an obstruction in the mast?
3.
The lift cylinder packing could be too tight in the bore of the cylinder
barrel.
—
Rebuild or
Replace Cylinder
Go to Step 4
4.
Check the flow valve on the extend hydraulic line for a restriction, i.e.
dirt.
—
Clean or Replace
Flow Valve
Go to Step 5
5.
Check if the lift down valve is opening completely.
—
Clean or Replace
Valve
Go to Step 6
6.
Is there a restricted hydraulic line (smashed)?
—
Replace Hydraulic Line
—
3-40
– JLG Lift –
3120728
SECTION 3 - TROUBLESHOOTING
3.10 HYDRAULIC LEAK TROUBLESHOOTING
Miscellaneous Hydraulic Leak Troubleshooting
Overview Of Procedure
This series of steps gives remedies for various areas of the machine where leaks could occur.
Table 3-31. Hydraulic Leak Troubleshooting
STEP
ACTION
1.
Oil leaking around the lift cylinder rod.
2.
Oil leaking around the cylinder fitting/flow valve.
3.
Oil leaking around the hydraulic lines.
4.
Oil leaking around the lift up valve.
5.
Oil leaking around the lift down valve.
6.
Oil leaking around the (Red) manual descent valve.
SPEC
YES
NO
—
Replace the Seal
at the end of the
Piston and
Cylinder Barrel
—
—
Tighten or
Replace Fittings
—
—
Tighten or
Replace
Hydraulic Lines
—
—
Tight Cartridge in
Pump Case
—
—
Tighten Cartridge
in Pump Case
—
—
Replace Lift
Down Valve
—
Note: Do not overtighten the nut on the solenoid in steps 4, 5, and 6.
3120728
– JLG Lift –
3-41
SECTION 3 - TROUBLESHOOTING
3.11 BASE FRAME COMPONENTS TROUBLESHOOTING
Caster Wheels Not Operating Freely
Check For These Obvious Conditions First:
• Is machine operating on a smooth, level surface?
Table 3-32. Caster Wheels Not Operating Freely.
STEP
1.
ACTION
SPEC
YES
NO
—
Go to Step 2
Lubricate or
Replace Caster
Housing
—
Go toStep 3
Lubricate or
Replace Wheel
—
Remove Debris or
Replace Wheel
—
Is the caster rotating freely?
2.
Is the wheel spinning freely?
3.
Is debris stuck in the plastic wheel?
Pot Hole Protection (PHP) Bars Will Not Set
Check For These Obvious Conditions First:
• Obstruction under pot hole bar on either side of machine.
• Obstruction around the actuator assembly at the base of the mast.
Table 3-33. Pot Hole Protection (PHP) Bars Will Not Set.
STEP
ACTION
SPEC
YES
NO
1.
Check the actuator cables for adjustment or damage.
—
Adjust or Replace
Go to Step 2
2.
Check the PHP limit switch(s) at both sides of the machine for damage, adjustment and for continuity through switch to ground when
bars are down.
—
Replace, Adjust
or Repair Wiring
—
3-42
– JLG Lift –
3120728
Corporate Office
JLG Industries, Inc.
1 JLG Drive
McConnellsburg PA. 17233-9533
USA
Phone: (717) 485-5161
Fax: (717) 485-6417
JLG Worldwide Locations
JLG Industries (Australia)
P.O. Box 5119
11 Bolwarra Road
Port Macquarie
N.S.W. 2444
Australia
Phone: (61) 2 65 811111
Fax: (61) 2 65 810122
JLG Industries (UK)
Unit 12, Southside
Bredbury Park Industrial Estate
Bredbury
Stockport
SK6 2sP
England
Phone: (44) 870 200 7700
Fax: (44) 870 200 7711
JLG Deutschland GmbH
Max Planck Strasse 21
D-27721 Ritterhude/lhlpohl
Bei Bremen
Germany
Phone: (49) 421 693 500
Fax: (49) 421 693 5035
JLG Industries (Italia)
Via Po. 22
20010 Pregnana Milanese - MI
Italy
Phone: (39) 02 9359 5210
Fax: (39) 02 9359 5845
JLG Latino Americana Ltda.
Rua Eng. Carlos Stevenson,
80-Suite 71
13092-310 Campinas-SP
Brazil
Phone: (55) 19 3295 0407
Fax: (55) 19 3295 1025
JLG Europe B.V.
Jupiterstraat 234
2132 HJ Foofddorp
The Netherlands
Phone: (31) 23 565 5665
Fax: (31) 23 557 2493
JLG Industries (Norge AS)
Sofeimyrveien 12
N-1412 Sofienyr
Norway
Phone: (47) 6682 2000
Fax: (47) 6682 2001
JLG Polska
UI. Krolewska
00-060 Warsawa
Poland
Phone: (48) 91 4320 245
Fax: (48) 91 4358 200
JLG Industries (Europe)
Kilmartin Place,
Tannochside Park
Uddingston G71 5PH
Scotland
Phone: (44) 1 698 811005
Fax: (44) 1 698 811055
JLG Industries (Pty) Ltd.
Unit 1, 24 Industrial Complex
Herman Street
Meadowdale
Germiston
South Africa
Phone: (27) 11 453 1334
Fax: (27) 11 453 1342
Plataformas Elevadoras
JLG Iberica, S.L.
Trapadella, 2
P.I. Castellbisbal Sur
08755Castellbisbal
Spain
Phone: (34) 93 77 24700
Fax: (34) 93 77 11762
JLG Industries (Sweden)
Enkopingsvagen 150
Box 704
SE - 175 27 Jarfalla
Sweden
Phone: (46) 8 506 59500
Fax: (46) 8 506 59534
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