BENDIX | BW2377 | User's Manual | BENDIX BW2377 User's Manual

Checklist for the Bendix® Air System Inspection Cup (BASIC) Test
Note: Follow all standard safety precautions. Only for vehicles using an air dryer.
Number of Days Since Air Tanks Were Last Drained: ________ Date: ___________Vehicle #: ____________
Service Writer - Please fill out
the information in this section. è Engine SN __________________________ Vehicle Used for: _______________Typical Load:________ (lbs.)
We will measure amount currently found when we get to step B of the test.
G“Excessive engine oil loss”amount described: ______________
Is the engine leaking oil? . . . . . . . . . . . . . . . . . . . . . Gno Gyes*
Is the compressor leaking oil? . . . . . . . . . . . . . . . . . Gno Gyes*
G Other complaint: ______________________________________
GNo customer complaint.
* Note: A confirmed complaint above does NOT mean that the compressor
must be replaced: the full BASIC test below will investigate the facts.
BASIC test starts here:
STEP A - Select one:
GThis is a low air use vehicle: Line haul (single trailer) with 5 or
less axles, or
GThis is a high air use vehicle: Garbage truck, transit bus, bulk
unloader, or line haul with 6 or more axles. Then go to Step B.
STEP B - Measure the Charging System Contents
1. Park and chock vehicle on level ground. Drain the air system by
pumping the service brakes.
2. Completely drain ALL the air tanks into a single BASIC cup.
3. If there is less than one unit of contents total, end the test now and
return the vehicle to service. Vehicle passes.
4. If more than one oil unit of water (or a cloudy
emulsion mixture) is found:
(a) Change the vehicle’s air dryer cartridge
- see Footnote 1,
(b) Conduct the 4 minute leakage test (Step D),
(c) STOP the inspection, and check the vehicle STOP
+ CK.
again after 30 days - see Footnote 2.
Otherwise, go to Step C.
Note for returning vehicles that are being retested after a water/
cloudy emulsion mixture was found last time and the air dryer
cartridge replaced: If more than one oil unit of water or a cloudy
emulsion mixture is found again, stop the BASIC test and consult the
air dryer's Service Data sheet troubleshooting section.
Footnote 1: Note: Typical air dryer cartridge replacement schedule is every 3 yrs/
300K miles for low air use vehicles and every year/100K miles for high air use vehicles.
Footnote 2: Caution: To get an accurate reading for the amount of oil collected
during a 30 day period, ask the customer not to drain the air tanks before returning.
(Note that 30-90 days is the recommended air tank drain schedule for vehicles
equipped with a Bendix air dryer that are properly maintained.) If, in cold weather
conditions, the 30 day air tank drain schedule is longer than the customer's usual
draining interval, the customer must determine, based on its experience with the
vehicle, whether to participate now, or wait for warmer weather. See the cold weather
tips in Bendix Bulletins TCH-008-21 and TCH-008-22 (included in Appendix B of the
Advanced Troubleshooting Guide).
Use the chart (label) on the BASIC test cup to decide the action to take.
Use the lower acceptance line for low air use vehicles, and upper line for high
air use vehicles (from Step A).
1. Record days since air
tanks were last drained.
2. Record amount
of oil found:
_________ days
_________ units
3. Action to
“Relay valve Gleaks oil / G malfunctions” . . . . . . . Gno Gyes*
“Dash valve Gleaks oil / Gmalfunctions” . . . . . . . Gno Gyes*
G“Air dryer leaks oil” . . . . . . . . . . . . . . . . . . . . . . . Gno Gyes*
G“Governor malfunction” . . . . . . . . . . . . . . . . . . . . Gno Gyes*
G“Oil in gladhands” . . . . . . . . . . . . . . . . . . . . . . . . Gno Gyes*
how much oil did you find? ________________________________
G“Oil on ground or vehicle exterior” . . . . . . . . . . . Gno Gyes*
amount described: ______________________________________
G“Short air dryer cartridge life”
replaces every: ______________ G miles, G kms, or G months
G “Oil in air tanks” amount described:_______________________
STEP C - How to Read the BASIC Test Chart
Checklist for Technician
Have you confirmed complaint?
Customer’s Complaint
(Please check all that apply)
No. of Axles: ____ (tractor) ____ (trailer) No. of Lift Axles: ____ Technician’s Name: ____________________
Also, indicate any customer
complaint below.
if oil level is at or below System OK.
If number of days is:
acceptance line for number
30-60 days (high air use)
of daysè
if oil level is above
30-90 days (low air use)
Go to Step D
acceptance line for number
of days è
if oil level is at or below System OK.
30-day acceptance line è
Return to service.
Stop inspection.
(if the number of days is
unknown, or outside the if oil level is above 30-day Test again
after 30 days. + CK.
limits above)
See Footnote 2.
Otherwise . . .
BASIC Test Example
An oil level of 4 units in a sixty-day period is within the acceptance area
(at or below the line) for both low and high air use vehicles. Return the
vehicle to service.
Sixty days since last air tank draining
Decision point
STEP D - Air Brake System Leakage Test
Park the vehicle on level ground and chock the wheels. Build system pressure
to governor cut-out and let the pressure stabilize for one minute.
1: Observe the dash gauges for two additional minutes without the service brakes
applied. 2: Release the parking brake and apply the service brakes (you may
use a block of wood to hold the pedal in position). Allow the air pressure to
stabilize, and then observe the dash gauges for 2 minutes. If you see a
noticeable decrease of the readings, repair leaks and repeat this test to confirm
that air leaks have been repaired. Return vehicle to service, but please repeat
BASIC test at next service interval. Note: Leaks can also be present in the
charging system, parking brakes, and/or other components.
If no air leakage was detected, and if you are conducting
this test after completing Step C, go to Step E.
STEP E - If no air leakage was detected in Step D
Replace the compressor. Note: If the compressor is within warranty period,
please follow standard warranty procedures. Attach the completed checklist to
warranty claim.
If, after a compressor was already replaced, the vehicle fails
the BASIC test again, do not replace the compressor again,
instead use the Advanced Troubleshooting Guide to
investigate the cause(s).
BW2377 ©2004 Bendix Commercial Vehicle Systems LLC. All Rights Reserved. 8/30/04. Printed in USA.
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