SEPARATING T H E TRACTOR
T o enable the tractor to be separated into its major units,
the following operations have been detailed: separating the
engine and front axle assembly from the remainder of the
tractor, removing the primary gearbox, and separating the
rear axle assembly from engine and gearbox assembly. For
full details covering dismantling the major units, after the
tractor has been separated, reference can be made to the
appropriate section.
TO SEPARATE THE ENGINE AND FRONT AXLE
ASSEMBLY FROM THE FRONT TRANSMISSION
Should it be necessary at any time to dismantle the
tractor in order to carry out repairs on the clutch or gearbox
the following general procedure should be applied disregarding any operation not associated with the type of
tractor concerned.
wiring at the right-hand side of the radiator cowl,
and ~eleasethe wires from their clip on the front end
of the right-hand side member.
5 Disconnect the two wires from the generator and
release them from the clip at the left-hand side of the
front mounting plate.
6 Release the main wiring from the two clips on the
tappet side cover bolts, and the clip under the front
of the battery tray.
7 Disconnect the Nlo wires from the starter relay
switch, and remove the cable from the starter motor
to the solenoid by disconnecting at both ends.
Disconnect the starter operating rod at the starter
end.
8
To Dismantle
1 Drain the cooling system through the two taps, one
on the radiator and one on the cylinder block.
2 Remove the bonnet by unscrewing the two screws in
the rear bracket and lifting the bonnet rearwards.
3 Disconnect the battery cables and remove the battery.
4 Pull out the snap connectors of the headlamp
Release the main wiring loom from its clip at the
top of the clutch housing on the left-hand side of
the tractor and tie the front part of the loom clear
of the front of the tractor.
9 Remove the temperature gauge bulb from the front
of the cylinder head and release the capillary tubing
from the two clips on the tappet side cover bolts.
Position the tubing clear of the front of the tractor.
10
Remove the fuel pipe from bewee,, the fuel
and the fuel lift pump.
Fig. 145
View o f Tractor on Dismantling Stand Tr/NMD 27
SEIJAKAY'IRG THE T R A C T O R
!1 Disconnect the governor control rod at the operating
lever end and the shutter control at both ends.
12 Disconnect the stop control cable at the lever on
the fuel injection pump by releasing the pinch screw.
3 Remove the front axle clamp (tool No. Tr/MD 3000)
and the front axle wedge (tool No.Tr 2!NMD 3004).
13 Disconnect the leak-off pipe at the rear of the
cylindes head by removing the banjo union bolt or
unscrewing the connection nut, whichever type is
fitted.
4 Remove the tractor dismantling stand (tool No.
Tr/NMD 27).
14 Remove the oil pressure pipe to oil pressure gauge
by disconnecting at both ends and releasing it from
its clip at the clutch housing on the left-hand side
of the tractor.
15 Disconnect the rubber hose from the air cleaner by
unscrewing the clamp at the air cleaner end only.
16 Remove the exhaust pipe, silencer and tail pipe
complete by removing the two bolts and one nut at
the exhaust manifold and the bolt from the silencer
bracket at the side member and the bolt securing the
tail pipe to the rear axle.
17 Remove the tool box and disconnect the steering drag
link from the drop 3rm by unscrewing
- the drag link
ball plug.
-
18 Support the engine and transmission, using the tractor
dismantling stand (tool No. Tr/NMD 27). Place
the two rail sections under the tractor and position
the engine and gearbox supports. (See Fig. 145.)
Note - I t will be necessary to disconnect the power take-off
lever link at the front end to allow the gearbox
support to be correctly located.
19 Place the frbnt axle wedge (twl No. Tr2,'NMD 3004)
in position to prevent movement between the engine
and front axle assembly.
20 Lock the track rod by means of the front axle clamp
(tool No. Tr/MD 3000).
21 Remove the four bolts from the rear of each side
member, securing the side members to the gearbox
housing and the bolts retaining the engine to the
gearbox.
Note - Do not forget the two bolts behind the side channels.
22 Withdraw the engine, radiator and front axle assembly
moving it forward until clear of the gearbox.
Note
- See
" Dismantling the Front Transmission after
Engine and Front Axle Separated " (page 117) if it is
desired to dismantle the gearbox
To Reassemble
1 Move the engine, radiator and front axle assembly
towards the front transmission, ensuring that the
mainshaft lines up with the clutch .pressure plate
spliines.
2 Replace the bolts retaining the engine to the gearbox
116
and the four bolts securing each side channel to the
gearbox housing.
5 Refit the tool box and reconnect the steering drag
link to the steering drop arm.
6 Refit the exhaust system by replacing the two bolts
and a nut at the manifold, the bolt securing thesilencer
bracket to the side channel and the bolt securing the
tail pipe to the rear axle.
7 Connect the rubber hose between the air cleaner and
inlet manifold by fitting the clamp in position at
the air cleaner end and tightening the screw.
8 Replace the oil pressure pipe between the cylinder
block and the back of the dash panel and refit the clip
to the clutch housing.
9 Replace the banjo union bolt and two fibre washers,
securing the leak-off pipe to the right-hand side rear
of the cylinder head or reconnect the connection nut
on the iarlier-type tractors.
10 Reconnect the stop control cable to the lever on the
fuel injection pump, and tighten up the pinch screw.
11 Refit the governor control rod at the operating lever
end and the shutter control rod at both ends.
12 Replace the fuel pipe between the fuel tank and the
fuel lift pump.
13 Carefully replace the capillary tubeofthe temperature
gauge bulb in the two clips on the tappet side cover
bolts and refit the bulb in the front of the cvlinder
head.
14 Refit the main wiring loom into its clip at the top of
the clutch housing on the left-hand side of the
tractor, replace the cable between the starter motor
and solenoid and reconnect the two wires to the
starter relay switch. Reconnect the starter operating
rod.
15 Refit the main wiring to the clip under the front of
the battery tray and the two clips on the tappet side
cover bolts, and reconnect the two wires to the
generator.
16 Reconnect the headlamp wiring by pushing in the
snap connectors at the right-hand side of the radiator
cowl and refit their clip to the front of the right-hand
side chassis member.
17 Refit the battery and reconnect the leads.
18 Replace the bonnet and fit the two screws securing
the rear bracket.
19 Refill the cooling system with clean water.
S E P A R A T I N G THE T R A C T O R
-
DISMANTLING T H E FRONT TRANSMISSION
AFTER ENGINE AND F R O N T AXLE SEPARATED
Note
T o carry out repairs to the primary gearbox it is necessary
to separate the engine and gearbox, and the following
additional operations must be carried out.
T o carry out repairs to the main gearbox, the gearbox and
rear axle must be separated to permit removal of the large
transmission gear (see page 118).
1 Drain the oil from the gearbox. (Front Transmission.)
To carry out further dismantling see
Front Transmission " section.
"
Gearbox-
T o Reassemble
?
2 Remove the split pin and clevis pin securing the
clutch relay lever to the cross shaft.
3 Disconnect the clutch release bearing retracting
spring and remove the release bearing.
4 Remove the split pin and clevis pin securing the
clutch release fork to the cross shaft.
5 Remove the collar retaining the clutch cross shaft in
the housing and withdraw the shaft and clutch release
fork from the housing.
6
Remove the split pin and clevis pin securing the
power take-off engagement lever to the selector shaft.
7 Remove the four bolts securing the power take-off
selector housing.
8
Note
Remove the six bolts securing the power take-off to
the gearbox housing.
- The left- and right-hand centre bolts are pilot bolts.
9 Remove the nut, spring washer and flat washer
securing the steering wheel to the shaft and remove
the steering wheel.
10 Remove the four bolts securing the front bracket of
the fuel tank.
Note
- The left-hand
rear bolt is the gearbox breather.
11 Remove the two bolts at the rear of the fuel tank and
lift the tank clear of the steering gear.
2 Refit the main gearhnx selector plate with four bolts.
Note
-
One of these bolts is the pivot pin for the power
take-off engagement lever.
3 Refit the primary gearbox selector housing to the
gearbox casing.
Note - On the diesel engine the starter control bracket i s
retained by the two left-hand bolts.
4 Locate the steering gear on the gearbox housing with
the five bolts and flat washers.
5 Refit the instrument box and reconnect the side and
tail lamp loom to the terminal under the box.
6 Refit the fuel tank and the two rear support bolts.
7
Refit the four bolts securing the fuel tank front support bracket. The left-hand rear bolt of this bracket
is the gearbox breather.
8 Refit the steering wheel using the large flat washer,
spring washer and nut.
9 Locate the power take-off housing. Fit and tighten
the pilot bolts in the left and right-hand centre holes.
Refit the four remaining bolts.
10 Secure the power take-off selector housing into place
with four bolts.
11 Reconnect the power take-off engagement lever to the
seleaor shaft. Refit rhe clevis pin and split pin.
12 Disconnect the tail and side lamp loom from the
terminal under the instrument box and remove the
assembly.
12 Enter the clutch cross shaft into the housing and
locate the clutch release fork.
13 Remove the five bolts securing the steering gear to
the gearbox housing.
13 Fit the collar and lock it to the shaft with a clevis pin
and split pin.
Note
- Flat washers are fitted under the bolt heads.
1'4 Remove the four bolts from the ~ r i m a r ygearbox
selector housing and remove the housing.
Note
- On the diesel engine the starter control bracket is
retained by two of these bolts.
a
1 Refit the belt pulley assembly with six bolts.
15 Remove the four bolts securing the main gearbox
selector plate and remove rhe plate.
16 Remove the belt pulley assembly.
14 Lock the clutch release fork to the shaft with a clevis
pin and split pin.
15 Refit the clutch release bearing and re-connect the
retracting spring.
16 Reconnect the clutch relay lever to the cross-shaft.
Fit the clevis pin and split
- pin.
.
17 Refill thegearbox to the " FULL" mark on the lillcr
plug boss with lubr~cantofcorrcct gradc 35 \hewn
in the Operators Instruction Hook.
TO SEPARATE THE REAR TRANSMISSION FROM
THE FRONT TRANSMISSION AND ENGINE
ASSEMBLY
To carry out repairs to the rear axle it is only necessary
to separate the rear transmission from the engine and
gearbox assemblv. To s u m o n the tractor durine this
operation use the tractor '&nantling stand ( t o z No.
TrINMD 273. (Fig. 145.)
1 Drain the oil from the rear axle.
2 Install the front axle wedge tool (tool No. Tr2!NMD
3004).
3 Lock the track rod by means of the front axle clamp
(tool No. Tr/MD 3000).
4 Pull back the rubber sleeve and disconnect the side
an6 tail lamp loom at the terminal beneath the
instrument box.
5 Release the clip securing the loom to the R.H.
front foot plate.
6 Remove
plate to
holding
Remove
the two bolts holding the R.H. front foor
the bull pinion shaft housing, three bolts
it to the bracket and three to the wing.
the footplate.
7 Release the brake pedal retracting springs and disconnect the brake cables.
8 Remove the bolt holding the brake locking lever
guide to the rear transmission housing, and detach the
guide.
9 Remove the two bolts holding the K.H. front foor
plate support bracket to the rear transmission housing
and remove the bracket.
10 Remove the two bults holding the L.H. front foot
plate to the bull pinion shaft housing, three bolts to
the support bracket and three bolts to the wing.
Remove the footplate.
11 Disconnect the clutch pedal retracting spring.
12 Remove the split pin and clevis pin holding the
clutch relay lever to the clutch pedal.
13 Remove the two bolts holding the L.H. foot plate
support bracket to the rear transmission housing.
Remove the bracket.
17 Remove the main gearbox selector housing. (Four.
bolts.)
18 Remove the remaining bolts holding the rear axle
housing to the gearbox.
Note
-
The top left-hand and right-hand bolts are pilot
bolts.
19 Disconnect the gearbox and engine assembly from
the rear axle.
TO RECONNECT THE GEARBOX AND ENGINE
ASSEMBLY TO THE REAR AXLE
1 Connect the gearbox and engine assembly to the
rear axle
2
Fit the two pilot bolts to the top left-hand and
bottom right-hand bolts to the flange joint.
3 Enter the power take-off extension shaft into the
housing and refit the bolts.
4 Bolt the tail pipe to the right-hand rear foot plate.
5 Refit the left-hand foot plate support bracket and
the two bolts securing the bracket to the rear transmission housing.
6 Reconnect the clutch pedal to the clutch relay lever
and reconnect the clutch pedal retracting spring.
7 Refit the left-hand front foot plate with two bolts
to the bull pinion shaft housing, three bolts to the
support bracket and three bolrs to the wing.
8 Refit the right-hand front foot plate support bracket
and secure it to the rear transmission housing with two
bolts.
9 Refit the brake Locking lever guide to the rear transmission housing with one bolt.
10 Reconnect the brake cables and the brake pedal
retracting springs.
11 Refit the right-hand front foot plate with two bolts
to the bull pinion housing, three bolts to the bracket
and three bolts to the wing.
12 Refit the remaining bolts to the front and rear
transmission housing flanges.
13 Secure the side lamp loom with the clip under the
right-hand foot plate.
14 Remove the bolt holding the tail pipe bracket to the
rear foot plate.
14 Refit main gearbox selector housing.
15 Remove the four bolts holding the power take-off
extension shaft housing to the rear axle casing and
withdraw the shaft.
15 Reconnect the tail and side lamp loom to the terminal
beneath the instrument box and replace the rubber
sleeve.
16 Locate the rail sections of the dismantling stands
and position the support under the gearbox,and the
support nnder the rear axle.
16 Remove the front axle damp (Tool No. Tr/MD
3000).
17 Remove front axle wedge tool (Tool No. Tr2/NMD
3004).
Note- It will be necessary to disconnect the power
take-off lever link at the front end to allow the gearbox support to be correctly located.
18 Refill rear transmission to correct level, as indicated
T o carry out further dismantling, see " Rear
Transmission " section.
by " FULL" mark on dipstick, with lubr~cantof
correct grade as shown in the Operators Instruction
Book.
-
THE CLUTCH
l ' h c clutch is of thc single dry platc type with a solid hub.
The clutch disc is pressed against the flywheel by a springloaded pressure plate. The clutch disc is free to slide along
the splines of the main d r i ~ ~
gear
e when the pressure of the
platc is released by the clutch withdrawal components.
(See Fig. 146.)
The threc clutch fingers pivot on yokes secured to the
cover and their outer ends are free to rotate in needle roller
bearings and plns mounted on bosses formed on the pressure
plate. As the clutch pedal is depressed the release arm
moves the release bearing into contact with the intler ends of
the clutch fingers. Movement of the inner ends of the
fingers moves the outer ends back, together with the pressure
plate, so compressing the clutch springs and freeing the
clutch.
With the engine running and the main gear lever in neutral,
the clutch disc, when released, remains stationary on the
maindrive shaft, the pilot bearing in the flywheel providing
the necessary support. The clutch pilot bearing only rotates
relative to the main drive shaft when the clutch pedal is
depressed.
The clutcb release mechanism is operatcd by the clutch
pedal through a cross-shaft and external linkage. (See
Fig. 146.)
The clutch is located in its own compartment which forms
Dart of the front transmission housinrr. The clutch release
bearing is of the pre-lubricated type and requires no lubricant
in service. The pilot bearing should be packed with grease
on assembly.
-
CLUTCH SHAFT
CLUTCH FORK
8
I\L>.,UI\L
I LP,,
C
CLUTCH FINGER
Fig. 147
Clutch Adjustment
Heavy Duty Clutch
Dumpers, sbovels, hydraulic loaders and other similar
machines adapted to suit the New Fordson Major Tractor
are fitted with a heavy duty clutch disc assembly. The
clutch disc differs from the standard disc in respect of the
facines. which are thicker. almost black in colour with metallic
parti&s inset and
visible on the surface. On no
account may the standard disc he fined in its place.
The heavy duty clutch disc assembly is fitted in conjunction with three spacers positioned between the cover and
flywheel to accommodate the increased thickness of the disc
and maintain the spriug pressure. Longer clutch to flywheel
retaining bolts are fitted.
Clutch Adjustment
RELEASE BEARING
PILOT BEARING
C L U T C H
DISC
TCH
LING
Sectioned View of Clutch
T h e clutch pedal free travel should be between II, ins. and
In service adjustment can be
effected to the external linkage between the cross-shaft and
the balance lever as shown in Fig. 147.
2 ins. (38.1 to 50.8 mm.).
Remove the split pin from the clevis pin, loose~lthe
locknut and then remove the clevis pin; this will enable
the clevis to be freed from the balance lever. Screwing the
clevis further on to the rod will reduce the free movement.
When the free travel of the clutch pedal has been readjusted,
fit a new split pin in the clevis pin and retighten the locknut.
D o not operate the tractor with the foot resting on the
clutch pedal as this may give rise to excessive wear of the
release bearing and clutch lining, necessitating frequent
adiustment of the clutcl~,in addition to causing loss of
power through clutch sli6.
119
THE CLUTCH
To R e m o v e Clutch Disc a n d P r e s s u r e P l a t e
1 separate the front axle and engine assembly from the
front transmission as described on page 115.
2 Unscrew the six bolts securing the pressure plate to
the flywheel to release the pressure plate and clutch
disc. In the case of the heavy duty clutch (see previous
page) do ndt lose the three spacers fitted between the
pressure plate cover and the flywheel. (See Fig. 148.)
Note
- Inspect the clutch disc to ensure that the linings
are not loose and that they are perfectly clean and free
from oil. The disc should be replaced if there are
signs of overheating due to slip or excessive wear.
Check that the rivets securing the boss to the clutch
disc are perfectly tight.
The pressure plate should be examined to make
certain that the springs or the face of the pressure
plate are not discoloured due to overheating.
Depress each clutch finger in turn, and release it
slowly to check for signs of the fingers sticking.
Fig. 149
Clutch Disc Locator
T o Replace
1 Position the clutch disc on the flywheel face with the
longest spigot away from the flywheel.
2 Insert the clutch disc locator (tool No. T r i D 7563)
through the splines of the clutch disc hub into the
clutch pilot bearing. (See Fig. 149.)
3 Locate the pressure plate assembly over the clutch
disc and refit the six mounting bolts and spring
washers. Tighten the bolts cvenly to a torque of
12 to 15 lbs. ft.
Note - If a heavy duty clutch is fittcd (see previous page),
do not forget Lhe thrcc spacers hrtwren cover and
flywheel also use six longcr securing bolts.
4 Rcmove the clutch disc locator T r D 7563.
5 Reconnect the front axle and enginc assembly to the
front transmission as described on page 116, and adjust
the clutch pedal free travel as described on page 119.
T o R e m o v e t h e Clutch Release Bearing
Note - The release bearing is of the pre-lubricated type and
should require little attention in service.
1 Separate the front axle and engine assembly from the
front transmission as described on page 115.
2 Unhook the clutch release bearing spring and remove
tile hub and bearing asscmbly from the fork.
3 Withdraw t h e bearing from the hub.
T o Replace
1 Fit the new bearing to the hub, thrust face towards
clutch disc.
2 Mount the bearing and hub assembly in position in
the fork and connect up the spring.
3 Reconnect the front axle and cngme assembly to the
front transmission as described on page 116, connecl
and adjust the linkage to give the correct pedal free
travel.
Fig. 148
H e a v y Duty Clutch
Clutch Pilot B e a r i n g
This bearing serves as a mounting for the front end of the
main drive shaft and rotates relative to the main drive
shaft when the clutch pedal is depressed.
The bearing is of the pre-lubricated normal ball radial
thrust type.
THE CLUTCH
T o Replace
1 Locate the release arm at the end of the cross-shaft,
fit the retaining circlip at the outer end, and tighten
the clamp bolt.
2 Position the large plain washer on the shaft and enter
the assembly in the housing locating the clutch fork
at the same time. Retain the shaft by means of the
collar, clevis and split pin.
3 Fit the two fork retaining clevis pins and secure by
means of split pins.
4 Mount the clutch release bearing and hub assembly
and fit the spring. Reconnect the clutch release rod.
5 Reconnect the front axle and engine assembly to the
front transmission as described on page 116 and adjust
the clutch pedal free travel.
Fig. 150
Removing the Clutch Pilot Bearing
T o Remove the Clutch Pilot Bearing
1 Separate the front axle and engine assembly from the
front transmission as described on page 115.
2 Remove the clutch disc and pressure plate as described
on page 120.
3 Withdraw the clutch pilot bearing from the flywheel,
dsing the bearing remover tool No. T r / D 7600-A, as
shown in Eig. 150.
T o Remove Clutch P e d a l
1 Disconnect the fulcrum rod between the clutch
balance lever and the clutch pedal.
2 Disconnect the left-hand side brake cable and remove
the circlip at the outer end of the cross-shaft.
Unscrew the brake lever clamp bolt, withdraw the
lever and extract its key.
3 Disconnect the clutch pedal return spring and slide
the pedal off the shaft. The bush may now be
renewed if necessary.
T o Replace
1 Locate the pedal on the cross-shaft and reconnect
the return spring.
2 Place the brake lever key in the shaft, position the
lever and tighten the clamp bolt. Refit the circlip
and connect up the cable.
3 Connect the fulcrum rod between the clutch balance
lever and the clutch pedal.
T o Replace
1 Locate the new pilot bearing in its location (baffle
face outwards) and tap into position using the clutch
pilot bearing replacer, tool No. Tr2/D 7600-B, as
shown in Fig. 151.
2 Refit the clutch disc and pressure plate and reconnect
the front axle and engine assembly
To Remove Clutch Release Cross-shaft
1 Separate the front axle and engine assembly from the
front transmission as described on page 115.
2 Unhook the clutch release bearing spring and remove
the bearing.
3 Remove the split pins retaining the two clevis pins
securing the clutch fork to the shaft. W'ithdrdw both
clevis pins.
4 Disconnect the clutch release rod at the front end.
Remove the split pin retaining shaft collar clevis pin,
withdraw the clevis pin and pull off the collar. Pull
the cross-shaft out of the housing, supporting the
clutch fork at the same time.
5 Remove the circlip at the outer end of the shaft,
unscrew the clutch release arm clamp bolt and
withdraw the arm from the shaft.
Fig. 151
Fitting the Clutch Pilot Bearing
THE CLUTCll
HYDRAULIC AUTOMATIC CLUTCH RELEASE
The hydraulic automatic clutch release provides positive
means of clutch disengagement under conditions of excessive
resistance to the earth working parts of the implement. The
unit, together with its upper link support bracket is completely interchangeable with the standard upper link and
support bracket, and the method of attaching the implement
to the tractor is in no way affected.
r
RECUPERATION VALVES
ADJUSTER
T h e hydrahlic automatic'clutch release consists of a
cylinder, piston rod, piston and recuperation valve assembly,
adjuster rod, adjuster piston and relief valve assembly.
The cylinder is sealed at both ends by synthetic rubber
glands, and the piston is sealed to prevent oil from being
forced past the piston into the reservoir, before sufficient
pressure has built up to open the relief valve. T h e unit is
completely self contained and has its own oil supply.
Operation of t h e T o p Link
When the implement is in work, the resistance of the earth
to the passage of the implement tends to rotate it about its
lower link mounting pins. The top link, fitted between the
rear of the tractor and the top of the implement opposes any
tendency for rotation and is therefore permanently in
compression when the implement is in work.
I
,.-W
I.
LRELIEF VALVE
PISTON
SPRING
NORMAL WORKING POSITION
r ADJUSTERRECUPERATION VALVES\CYLINDER7
T h e hydraulic automatic clutch release takes the place of
the standard top link, and when in the "Normal working
position" position, oil between the piston head and the end
of the cylinder is trapped by the relief valve as indicated by
the dark shaded area in Fig. 152 "Normal working position."
When the earth working parts. of the implement meet an
obstruction, the compressive end loading on the top link
will build up sufficient pressure in the oil at the front of the
piston head to force the relief valve off its seat, and allow
the oil to flow past the valve to the reservoir as indicated by
the arrows in Fig. 152 "Clutch release". This wil! allow the
cylinder to slideiforward along the piston rod and operate
the linkage to disengage the clutch.
When the tractor is brought to rest, and the implement
lifted out of the ground clear of the obstruction, the weight
of the implement will place the top link in tension. This will
cause the cylinder to slide back along its piston, a depression
will be created inside the cylinder which will draw the recuperation valves off their seats and allow oil to be drawn from
the reservoir into the cylinder recharging it ready for the next
operation, as illustrated in Fig. l52 " Recuperation."
RELIEF VALVE
RELIEF VALVE
SPRING
O
PISTON
CLUTCH RELEASE
RECUPERATION VALVES
CYLINDER^
r ADJUSTER
Operation of the Linkage
As the cylinder moves forward, the buffer which is
connected to the automatic clutch release by means of an
attachment plate, is also moved forward (see Fig. 154).
This movement causes the cross-shaft to be rotated so
moving the cam which is rivetted to the L.H. end of the
shaft.
The cam bears against the outer spring loaded pawl of the
release hand lever assembly, and as it is rotated it moves the
release lever sector rearwards. The bell crank lever rod is
moved rearwards in turn and the clutch is disengaged (see
Fig. 153).
The clutch is retained in the disengaged position, by the
spring loaded plunger on the inside of the release hand lever
RECUPERATION
RELIEF VALVE
SPRING
Fig. 152
Diagrammatic Representation of Operation of Top Link
T H E CLUTCH
engaging in the rcccss of the fixed cam on the uppcr link
support bracket.
Note - In some instances on car!v units, a .build up o j
tolerances on the release hirnd lever assemb!~and linkage'gove
rise to a condition where the clurch wus nor f1rl1.v disengaged
when the top link was under full compression. As 0 resulr, [he
compressive end loading applied to the piston rod by the tractor
failing to stop has snlficiexr to bend the rod.
T o overcome this condition in service approximately .I25 ins.
(3. l 75 mm.) of metal should be removed fronn rhe verticalface
of the fired cam (see Fig. 154).
Later units embody din~ensional change to prevent this
condition from arising.
When the tractor has been brought to rest after discneaecmcnt of the clutch the gear
- lcvcr should be moved
into the neutral position.
T h e clutch mav be re-engaged b y further depressing the
clutch pcdal, and by movingt& rcliasc hand lcv& rearwards
at the samc timc. 'l'hc spring loaded plungers will be raised
clear of the two cams allowing the clutch pedal linkage to
become operative.
U
'The obstruction should be cleared by reversing slowly,
and raising the implcmcnt nt the samc timc. When the
implcmcnt has bccn complctcly or partially raised, its weight
will cause cxtcnsion uf the top link, in which position it will
he recuperated and re-sct for further work. T h e release
hand lcvcr will he automatically returned to its normal
pusition.
Adjustments
T h e only adjustment necessary to the automatic clutch
rclcasc is setting thc rclicf valve to provide a suitable breaking
load for varying soil conditions in cultivating operations.
T h e rclicf valve is easily adjusted by removing the unit
froin the tractor.
Adjusting t h e Relief Valve
Linc up the hole in the ball joint with thc hole in the
tractor cnd of the link. A screwdriver can now be inserted
through thcsc holes, and the relief valve adjusting rod can
be screwed in or out as rcquired.
T h e average setting of the adjusting rod from the fully
tightened position for general conditions is as follows:Light work . .
..
..
..
7 to 9 turns
Heavy work . .
..
..
..
5 to 7 turns
T h e relief valve should be set to operate at a pressure
slightly abovc that required to overcome normal resistance
generated by the implcmcnt, taking into consideration the
type of soil, depth of operation etc., otherwise extensive
damage to the implcmcnt may result if obstructions are
encountered.
If opcrating conditions arc such that a setting above that
for which the unit is alrcady set is required, the adjusting
rod may be screwed in a clockwise direction until the necessary breaking load is obtained.
For reducing t h e opcrating pressure the adjusting rod
should be turned anti-clockwise.
Fig. 153
Hydraulic Automatic Clutch Release L l n k a ~ r
l23
THE CLUTCH
Maintenance
Rcmovc the cxisting clutch pedal to balance lcvcr rod.
T h e unit is complefely self contained and does not require
lubricating, as it operates in its own supply. T h e oil capacity
is a half pint of hydraulic Ruid (Part No. M-100502-C), and
the filler plug,.and air bleed plugs arc clearly illustrated in
Fig. 155.
Replace with the slottcd rod and fulcrum link, so
that the slot in the rod end fits into the forkcd end
of the clutch pedal (sec Fig. 153).
Remove the two lower front bolts from the nearside
axle shaft housing, and fit the hcll crank lcvcr bracket;
retain with two i),ins. (14.29 mm.) by 2: ins. (57.15
mm.) bolts and spring washers.
I n thc event oSthc unit operating, and so causing the clutch
to be disengaged without obstructions being cncountcrcd,
it may bc due to insufficient oil, incorrect rclicf valvc adlustment or air in the system. With the unit detached from the
tractor or implement, it should not he possihlc to compress
the link morc than ,I, ins. (1.583 mm.) by hand. Any
movcmcnt in excess of this indicates that the unit rcqulrcs
topping up or hlccding or both.
Connect the bell crank lever to its bracket, and retaln
with a clcvis pin and split pin. T h e hole for the
adjustable bell crank lcvcr to sector rod must he to
the rcar.
Fit the non-adjustable fulcrum link rod between the
hell crank lcvcr and the fulcrum link. T h e slotted
end of thc rod fits in the forkcd end of thc bell crank
Icvcr.
T o Fill a n d Bleed t h e Unit
I
Screw the rclicf valvc adjusting rod right in.
2
Loosen ~ h air
c hlccd plug
Fit the long adjustable bell crank lcvcr to scctor rod
to the hcll crank lcvcr but do not connect the adjustable clcvis to the scctor at this point.
3 Completely comprcsa the unit by hand
4
'l'ighlcn the air hlccd plug.
Push the rcleasc hand lcvcr forward as far as possible
5
Rcmovc 11ic oil lillcr plug and pour half a pint of
hydraulic lluid (I'art Nu. M-100502-c:) slowly into the
rcscrvoir thrtugh the filler plug. Air will now hc
displaced from the oil ways and ~ h cunit should hc
rocked gently to assist displacing it. 'l'his is imporvant.
5
Replace the lillcr plug and tihrc washer lo<~scly.
11
l'ilt ~ h unit
c approximately 30" with the air hlccd plug
uplwrrnost.
Pull the buffer rearwards, avoiding the bell crank
lcvcr rod clcvis, thus rotating the cross-shaft away
from the tractor.
I'lacc the hydraulic clutch rclcasc in its location in
the uppcr link support bracket, fit the retaining pin
and linch pin. Secure the unit to the buffer by means
of- the attachment plate, securely tightening the
attachment plate bolt.
7
lixtcnd the unit so that the oil will be drawn from the
rcscrvoir into the spacc at the head of the pisu~n.
X
I.wiscn the air hlccd plug in the rcar cover, and gently
tap the pistonrod to cxpcl any air which will be in the
system, and tighten the hlccd plug.
1
(:heck the unit for compression hy hand. If morc than
, ins. (1.588 mm.) lice movement 01' the rod is
possihlc, thc ahovc procedure will have to be rcpcatcd.
Do n o t a t a n y t i m e extend t h e u n i t whilst t h e
bleed plug is loose.
10 Will1 thc link extended and placed in t l s horizontal
position and llle tiller plug still loosc, remove the oil
levcl plug liom the left-hand side of the cylinder,
whcn the surplus oil will drain away.
Tighten the oil levcl plug and tiller plug securely.
II
Adjust the rclicf valve as described previously.
I'ull the rclcasc hand lcver assembly to the rear, so
that thc inside spring loaded plunger is on top of the
insidc cam, and the outside plunger is abutting the
outside cam.
Adjust the clcvis end of the bell crank lcvcr rod so
that the holes just line up with the hole in the scctor.
Insert the clcvis pin and secure it with a split pin.
Note:
O n n o account p u l l t h e r o d t o t h e sector t o fit t h e
clevis pin.
T h e automatic clutch release and linkage assembly is
now ready for work.
T o R e m o v e t h e Assembly
I
Disconnect the bell crank lcver rod at the scctor
2
Rcmovc the attachment plate from the uppcr link
3
Remove thc linch pin and link retaining pin, and
remove the uppcr link.
Installing t h e H y d r a u l i c A u t o m a t i c C l u t c h Release
When it is dcsircd to install the hydraulic automatic clutch
rclcasc on tractors not so equipped, the following proccdurc
should he adopted.
I
Remove the existing uppcr link,&pport bracket and
install the new uppcr link support bracket assembly
(sec Fig. 154). 'l'his assembly is secured to the rear
transmission housing by the same four bolts and
washers.
2 Attach the buffer to the legs of the cross-shaft, and
secure by means of a clcvis pin and split pin at each
side.
4 Remove the four bolts and the uppcr link support
bracket assembly from the rear transmission housing.
T o Replace t h e Assembly
1 Fit the uppcr link support bracket assembly and
secure to the rear transmission housing with four
bolts and spring washers.
2 l'ush the release hand lever forward as far as possible.
3
Pull the buffer rearwards avoiding the bell crank lever
rod clevis thus rotating the cross-shaft away from the
tractor.
6-
T H E CLUTCH
4
Placc the automatic clutch rclcasc unit in its location
in thc upper link support bracket. Fit the retaining
pin and linch pin and secure the unit to the buffer
by mcans of the attachmcnt platc, sccurcly tightening
the attachment plate bolt.
5 Ensure that the clutch is engaged, and then move
the relcasc hand lever rearwards until the outside
spripg loadcd piungcr is abutting the outside cam,
and'the inner plungcr is on top of the inside cam.
6
Adjust the clevis of the bcll crank lcver rod so that
the l~olcsline up with the hole in the
hand
lcvcr
Insert the clcvis in t h r o u ~ hthe rod
~- sector.
and scctor, and sccure with a split pin.
~~
~
~
5 Remove the four bolrs which retain thc piston rod
scal housing to'the cylinder, and withdraw the piston
rod and piston assembly together with the seal housing.
6 Remove the grub screw which locks the piston
assembly to the piston rod.
7
Unscrew the piston assembly from the rod, taking care
not to lose the relief valve assembly which is looscly
located in the bore at the rca: of the piston. Remove
rhr
w.a-l.
-.. niston
.......
..
8
T h e piston rod seal llousing can now be ~ r c s s e doff
the piston rod by hand, and the seal removed.
9
Ren~ovethe relief valve spring from the borc in thc
piston rod. If it is required to remove the adjustcr
rod and piston, proceed as follows:-
10
Line up the holc in the ball joint with the axial holc
in the end of the upper link. Insert a screwdriver
through the aligned holes and turn the adjuster anticlockwise to remove it.
II
T o remove the adjuster piston, it will be ncccssary
to inscrt a brass or copper drift through the holcs
and gently tap out the piston. Damage to the horc
will affect the range of relief valvc adjustment and
thcreforc the above operation requires care.
~
T o Dismantle the U p p e r Link
1 Rcmovc the unit from the tractor, extract the six
bolts securing the top cover and rcmovc the cover
toecthcr with its ~ a s k c t .
-
2 Rcmove thc spring and bamc platc.
3 Drain the oil from the reservoir into a suitable
container.
4 Remove the four bolts sccuring the scar cover,
remove the covcr and allow the oil in the cylindcr to
drain into a container.
12 Extract the two recuperation valve plate retaining
Fig. 154
llydrnulic Automatic Clutch Helrnsc
125
TfiE CLUTCH
Replace the four bolts and washers in the piston seal
housing and tighten fully.
14 Fill the unit with the correct grade of oil.
Fit a new oil sealing ring into the counter-bore at
the rear of the cvlinder and redace the rear cover
plate and retaining bolts.
expel all air from behind the piston.)
16. Bleed the unit.
Fit the baffle plate and spring, and replace the top
cover sasket. Re-fit the to^ cover and secure bv six
bolts.
?
17 Adjust the relief valve breaking
- load and replace the
on the tractor.
-
15 Fit the adjusting rod and screw it right in. (This will
4
m
FRONT TRANSMISSION-GEARBOX
The front transmission-gearbox has six forward and two
reverse speeds, controlled by a main and primary gear
levers.
take-off gear. The hydraulic pump, when fitted, is driven
by a gear located at the rear of the power take-off extension
shaft.
7
The main gear lever selects three forward and one reverse
gear positions and the primary gear lever provides high or
low gear ratlos (see Figs. 157, 158 and 159). The gear lever
positions are cast on the front of the rear transmission cover.
The drive is taken from the engine, via the clutch, to the
main drive shaft and transmitted through the primary gearbox
to the main gearbox, which is connected to the rear axle by
the transmission drive pinion. A power take-off shaft
(optional equipment), independently controlled by a hand
lever, is driven from the combined lower shaft and power
A raised power take-off is available as an accessory and
can be fitted to the standard power take-off to takz care of
certain operating conditions requiring the power take-off to
be at a greater height than the standard fitment. (See
" Power Take-Off Equipment " section.)
A two-speed belt pulley (additional equipment) is located
at the right-hand side of the front transmission housing and
is driven by the pulley drive bevel gear. The full details of
gearbox overall ratio, road speeds and all relative data are
shown in tabulated form overleaf.
MAIN UPPER SHAFT PIN10
PULLEY DRiVE BEVEL GEAR
PRIMARY GEAR HOUSING
PRIMARY SELECTOR FORK
PRIMARY UPPER SHAFT
AND GEAR
PRIMARY UPPER
SHAFT DOG
CLUTCH FORK
TCH PRESSURE
TCH RELEASE
TRANSMISSION
LARGE GEAR
CLUTCH SPRING
POWER TAKE-OFF IDLER GEAR
AND SHAFT
LOWER SHAFT DOG
MARY LOWER SHAFT
POWER TAKE-OFF
EXTENSION SHAFT
MAIN LOWER SHAFT AND DOG
MAlN LOWER SHAFT P
REVERSE IDLER
MAIN LOWER SHAFT GEAR
REVERSE PINION
Fig. 157
Sectioned View of Front Transmission-Gearbox
FRONT TRANSMISSION- GEARBOX
8
RATIO
ROAD SPEEDS
800
Gearbox
R.P.M.
Tyre Size
Overall
11-36 &
1430
1st Gear
2nd Gear
3rd Gear
4th Gear
5th Gear
6th Gear
Low Reverse
High Reverse
Belt Pulley
6.62
4.7
3.68
2.615
1.875
1.043
4.91
2.73
..
..
123.0
87.3
68.4
48.6
34.8
19.3
91.0
50.7
M.P.H.
1.04
1.46
1.86
2.63
3.66
6.58
1.40
2.52
11-38
M.P.H.
1.08
1.52
1.93
2.72
3.80
6.85
1.45
2.61
1,200
R.P.M.
1,600 R.P.M.
Tyre Size
11-36 &
11-38
14-30
M.P.H.
1.56
2.19
2.80
3.94
5.49
9.87
2.10
3.77
Tyre Size
11-36 ?L
1430
M.P.H.
1.61
2.27
2.90
4.09
5.70
. 10.2
2.18
3.92
M.P.H.
2.07
2.92
3.73
5.25
7.32
13.16
2.80
5.03
11-38
M.P.H.
2.15
3.03
3.87
5.45
7.60
13.7
2.9
5.22,
Pulley speed at 1,400 R.P.M.-High speed 1,400 R.P.M.
Low speed
779 R.P.M.
Pulley diameter 84 ins.
Direction of Rotation-Clockwise.
722 R.P.M. at 1,600 engine R.P.M.
Power Take-Off
Raised Power Take-Off
Shaft diameter-Rear End
13
ins.
6-spline
~
i of ~ ~~ ~ ~ ~ ~ i ~~ ~ ~- ~ l j(B.S.I.
~ ~&
~ kS.A.E.
~ ~Standards).
i ~ ~ ,
540 R.P.M. at 1,600 engine R.P.M.
I
GEARS AND SHAFTS (All Models)
Description
Part No.
Primary lower shaft gear and power takeoff gear . .
.. ..
.
Main drive shaft and dog . .
.. .
Pulley drive bevel gear
.. .. .
Transmission large gear . .
.. . .
Main lower shaft and dog . .
..
..
Mair lower shaft gear
.. .. ..
Primary upper shaft and gear
.. ..
Primary lower shaft
.. .. . .
Reverse pinion
. .. .. .
Main upper shaft and gear
..
..
Low gear
.. .. .. .. . .
Main upper shaft pinion . .
.. ..
Primary upper shaft dog . .
.. ..
Main lower shaft pinion
. .. ..
Reverse idler
.. . . . . ..
..
.
.
.
.
I
Identification
22 ext. teeth 30 ext. teeth 6 splines
16 ext. teeth 8 dog teeth
21 teeth l 0 splines
20 int. teeth 34 ext. teeth 10 splines
8 dog teeth 10 splines and 6 splines
17 int. teeth 24 ext. teeth 10 splines
17 int. teeth 23 ext. teeth 10 splines
6 splines
17 teeth
13 teeth
13 int. teeth 27 ext. teeth
17 teeth
8 dog teeth 6 splines
20 teeth
20 teeth
.
.
Fig. 158
Gearbox Data
I
FRONT TRANSMISSION- GEARBOX
GEARBOX ADJUSTMENTS
Shaft end-float adjustments are taken care of in design by
manufacturing tolerances and, provided that the outlined
assembling procedure is followed, the correct working
clearances will be established.
PRIMARY GEAR LEVER
Removing 2nd Dismantling the Primary Gear Lever
1 Remove the engine bonnet, steering wheel, oil
pressure gauge pipe, stop control cable (Diesel only)
and instrument box (place the latter to one side).
Disconnect the radiator shutter control.
2 Disconnect the leak-off pipe and main fuel supply
from the fuel tank. Next remove the fuel tank and
front support bracket. (Four bolts secure front
bracket and two at the rear.)
3 Remove the steering column (see " Steering Gear "
section) and then unscrew the four bolts securing the
primary gear lever assembly to the front transmission
housing, turn the gear lever assembly to the rear and
tilt it over as it is withdrawn.
Note - The fuel tank rear mounting- bracket forms part of
this assembly.
4 Extract the rivet retaining the selector lever and
withdraw the lever, shaft and fork. Remove the oil
seal.
Reassembling the Primary Gear Lever
1 Fit a new oil seal and position the shaft, fork and
gear lever in the housing and rivet the lever securely
to the shaft.
2 Mount the gear lever assembly in position ensuring
the end of the connector enters its location in the
lower shaft, tighten up the four bolts.
Note - The correct location of the end of the gear connector
can be observed through the steering gear mounting
hole.
3 Refit the steering gear assembly, fuel- tank front
support bracket (four bolts at front, two at rear:
nearside bolt is gearbox breather), governor control
bracket, starter control lever, fuel tank and the control
box.
4 Reconnect stop control cable, starter control, shutter
control, oil pressure gauge pipe, fuel leak-off and
main supply pipes.
5 Refit the steering wheel and engine bonnet.
TRANS. LARGE
TRANS. LARGE
L
1st GEAR
3rd G EAR
2nd GEAR
M A I N DRIVE D O G
REVERSE IDLER
REVERSE IDLER
PRIMARY LOWER
EVERSE PINION
TRANS. LARGE
PRIMARY UPPER
-
REVERSE
- HIGH
REVERSE
..,
- LOW
MAIN
TRANS. LARGE
DOG
1
TRANS LARGE
GEAR
4th GEAR
5th GEAR
Fig. 159
Gear Positions
6th GEAR
FRONT TRANSMISSION- GEARBOX
MAIN GEAR LEVER
A
Removing and Dismantling Main Gear Lever
A
-,
-
r TOOL No.
1 Remove the four bolts retaifiing the main gear lever
assembly to the housing.
Note - One of these bolts retains the wiring loom clip in
position. ?
Lift out gear lever assembly.
2 Unscrew the knob, remove the snap ring and lift off
the spring and cap.
3 Remove the screw retaining the lever in the housing
and separate the two parts.
Reassembling the Main Gear Lever
1 Install the lever in the housing and securely tighten
the retaining screw.
2 Mount the cap and spring in position and fit the snap
ring.
3 Fit the assembly, and a new gasket, to the front
transmission housing. The rear right-hand bolt also
retains the wiring loom clip.
SELECTOR HOUSING AND CLUTCH BALANCE
LEVER
1 Disconnect the operating rods and remove the selector
fork plate (left-hand side of housing) four bolts.
2 Remove the clutch fulcrum lever after extracting the
split pin.
Fig. 161
Removing the Primary Lower Shaft Bearing
3 Remove the fork retaining rivets and extract the top
shaft by tapping from the loose plunger end.
Remove the loose plunger, then the two spring-loaded
plungers and their springs.
4 Tap the lower selector shaft out of the housing and
fork.
Reassembling the Clutch Balance Lever and Selector
Fork Plate
1 Refit the lower selector shaft and fork in position.
Note - This fork is identified by the short stalk and is
fitted with the end of the shaft with three indentations
at the spring-loaded plunger end upwards.
2 Rivet the fork to the shaft (rivet head uppermost).
3
Insert the loose plunger, spring-loaded plungers and
their springs.
4 Refit the upper shaft and fork (the three indentations
at the spring-loaded plunger end downwards).
Rivet in position (head uppermost).
5 Refit the selector fork plate to the housing (four bolts
and lockwashers) and install the clutch fulcrum lever,
secure with a new split pin.
PRIMARY AND MAIN GEARBOX
Fig. 160
Removing the Primary Gearbox
Note - The operations covering " Separating the engine
from the front transmission-gearbox and the rear
transmission from the front transmission," are fully
covered in the appropriate section on pages 115 to 118.
The following opera5ons give the subsequent sequence
after the front transmission has been separated from
the tractor.
a
FRONT TRANSMISSZON-GEARBOX
@
Removing the Primary Gearbox
1 Separate the front transmission from the engine or
the rear transmission as desired. Refer to pages
115 to 118 for full details.
For details of the correct sequence for dismantling
and reassembly of the power-take off assemblies, refer
to the Power Equipment " section.
4 Unscrew the seven wire-locked securing bolts, fit two
locating studs Tr/MD 6050 at the right-: and left-hand
centre bolt holes and then ease the primary gearbox
out of the main housing (see Fig. 160).
Note - The box is spigotted and dowelled.
To Dismantle the P r i m a r y Gearbox
a
Note - All bearings and cups must be kept in original
pairs.
1 Withdraw the main drive shaft, oil seal retainer and
bearing out of the housing after removing the wirelocked bolts (the bearing is a sliding fit in the housing).
2 Remove the circlip and press the bearing off the main
drive shaft, using tool No. Tr/D 7006, then remove
the cup from the dog gear of the main drive shaft.
3 Remove the split pin and unscrew the transmission
brake adjusting nut, lift off the brake springs and brake
plates, then remove the reverseidler gear and withdraw
the shaft. If a transmission brake is not fitted the
reverse idler is secured by a bolt and two retainers.
4 Slide the lower drive pinion and reverse pinion from
the main lower shaft after removing the small bearing
from the rear of the shaft, using tool No. T r / D 7006.
5 Remove the upper and lower shaft bearing locking
plates after cutting the locking wire and unscrewing
the bolts. (These plates are not interchangeable.)
6 Lift the main lower shaft, gear and bearing from the
gearbox and dismantle further by removing the gear
retaining circlip. Press the shaft out of the gear and
bearing, using tool No. Tr/D 7006. Reverse the
tool adaptor and press the bearing off the gear.
The cup can then be removcd from the main lower
shaft dog.
7 Remove the primary lower shaft, lower shaft gear and
power take-off drive gear, after withdrawing the small
bearing from the end of the shaft, using tool No.
Tr/D 71 18-Al. Split adaptors fit behind the bearing
as shown in Fig. 161.
8 Remove the end plate (four bolts) and locate the hollow
tool (Tr/D 77105) to the dog gear and the drive shaft
into the hollow portion of the tool. (See Fig. 162.)
Move the dog gear along the splines to facilitate lifting
out the primary lower shaft and power take-off gear.
(The dog gear is left in the position in the selector
fork.) Remove the shaft.
9 Push the large bearing out of the housing.
10 The primary upper shaft and gear, dog gear and
bevel gear can now be withdrawn after removal of the
circlip from the groove in the housing and withdraw
the small bearing from the end of the shaft. (Tool
No. T r / D 7118-Al.)
11 Straighten the tab of the bevel gear lockwasher,
engage the tool T r / D 77105 in the dog gear teeth and
unscrew the bevel gear nut.
Support the bevel gear, lift out the upper shaft and
gear, nut, lockwasher and dog gear. Remove the
bearing from the gear using tool No. T r / D 7006.
To facilitate removing the cup from the inside of the
gear, two holes are provided in the shaft gear so that a
suitable tool may be inserted and the cup driven out.
12 The selector shah, selector fork and lower shaft dog
gear may now be removed after cutting the locking
wire and removing the retaining screw. Place a
cloth over the selector ball passage as the shaft is withdrawn to retain the ball and spring.
13 Remove the welsh plug from the end of the shaft
housing.
Reassembly of P r i m a r y Gearbox
1 Locate the selector fork (locking screw towards
the front) and selector shaft dog (teeth to gearbox).
Enter the spring and ball, using a tapered pilot and
move the shaft into position, tighten
and lock the screw
wkh wire, then refit the welsh plug.
Fig. 162
Removing the Primary Lower Shaft
FRONT TRANSMISSION- GEARBOX
2 T o assemble the primary upper shaft and gear, dog
gear and bevel gear, fit the dummy end plate (Tr/D
77012) in the front face to stabilise the housing during
assembly, then move the selector shaft downwards and
locate the dog gear in the fork (teeth downwards).
Position the nut, lockwasher and bevel gear on top of
the dog gear then press the bearing on to the primary
upper shaft, and enter the primary shaft, gear and
bearing into the bevel gear and dog gear splines, then
gently tap into position. Tighten up and lock the
bevel gear nut, using tools T r / D 77025 and T r / D
77105.
3 T o refit the primary lower shaft and lower shaft gear
and power take-off gear, first enter the large bearing
at the front of the box and refit the dummy end plate.
Ensure the circlip is fitted in the lower shaft gear and
power take-off gear, lift the selector dog and place
the gear in position (shoulder towards bearing).
Tap the smaller roller bearing on to the lower shaft
and pass the shaft through the dog gear and lower
shaft gear and power take-off splines. Drive into
position (shaft against surface of dummy end platc).
4 The reassembly of the main drive shaft, reverse pinion
and lower shaft pinion is most conveniently carried out
before fitting into the gearbox. Locate the large
bearing on the lower shaft, pass the gear (shoulder first)
along the gear to engage the larger splines. (See Fig.
163.) Place this assembly in tool No. T r / D 7006 and
press the shaft through the gear. As it moves through,
locate the bearing on the gear shoulder. Fit the
circlip behind the gear and remove the assembly from
the tool.
Locate the reverse pinion and lower shaft pinion
(selector fork flanges together) fit the small roller
Fig. 164
Installing the Main Lower Shaft, Gears and Bearings
bearing on the end of the shaft and place the assembly
in position in the housing. (See Fig. 164.) I f slight
pressure is required to seat the large bearing in the
housing, it must be applied to the main lower shaft
gear and not the end of the shaft, otherwise the circlip
will be damaged.
5 Refit the lower shaft and upper shaft bearing locking
plates. (Two bolts each with heads wired together
through the centre holes in the plate.)
6 Pass the transmission brake and reverse idler shaft
through its location in the housing and fit one
stationary plate, reverse idler (recess towards the
housing) and then alternate with first a stationary
plate and then a revolving plate.
Note
- Six stationary and
five revolving plates are fitted.
Locate the small spring on the shaft, fit the retainer
plate, coil spring and locknut. T o correctly adjust the
brake the measurement from the head of the nut to
the inner face of the primary gearbox housing flange
must be between 13.870 ins. and 13.895 ins. Do
not forget to fit a new split pin.
If a transmission brake assembly is not fitted the
reverse idler gear is secured by a bolt, two retainers and
a self-locking nut. The retainers are fitted with the
shoulders located in the ends of the tubular shaft.
Tighten the self-locking nut thoroughly and check that
there is 0.010 in. to 0.025 in. (.254 to .S08 mm.) endfloat between the retainer and the hub of the reverse
idler gear. If not satisfactory press the shaft in, or
out, to obtain the desired endfloat.
Fig. 163
Fitting the Main Lower Shaft, Gear and Bearing
Remove the dummy end plate (Tr/D 77012) and fit
the original plate and gasket. (Four bolts and
locking wire.)
FRONT TRANSMISSLON-GEARBOX
@
8 Position the small roller on the spigot of B e primary
upper shaft and locate the circlip in the inner groove
in the primary gearbox. Next, fit the main drive shaft
and oil seal retainer.
Press the bearing on the main shaft (tool No.
Tr/D 7006) and fit the circlip. Check that the bearing
cup is fitted in the end of the main drive shaft gear and
engage the shaft to the primary upper shaft dog.
Fit a new oil seal in the retainer (lip towards gearbox)
using the tool No. Tr/D 7052-B, loc&e the retainer
and gasket (clutch spring lug to bottom), four bolts
and locking wire.
To Dismantle .the Main Gearbox
~ o i e- All bearings and cups rnust be kept i n original pairs.
l Withdraw the clutch shaft, and remove the primary
gearbox as described on page 133.)
a
2 Position the transmission hand brake cam suitably to
remove the transmission large gear and the main upper
shaft gears by withdrawing the split pin, bolt and
locking tab from the retaining nut, then unscrew the
large gear retaining nut and withdraw the locking
washer and sleeve.
Remove the oil seal retainer bolts (four) and screw
the four legs of the tool Tr/MD 7150-A, in the holes.
Tighten up the centre screw to push the transmission
large gear halfway out of the housing. (See Fig. 165.)
Note - Do not use shock methods to remove this gear,
otherwise it will burr over the end.
2 If the transmission hand brake lever and shaft has
been removed refit in position and rivet securely.
3 Refit the transmission large gear and main upper shaft
and gear. Locate the transmission large gear bearing,
oil baWe and new oil seal and retainer and secure with
four bolts, then drive the transmission large gear
half-way into the bearing, using tool No. Tr/MD
7150-B. Ensure that transmission hand brake lever
cam is positioned to provide clearance.
4 Press the large bearing onto the rear of the main
upper shaft, using tool No. T r / D 7006, then slide on
the low gear and upper shaft pinion (selector flanges
together) and drive the small roller bearing on the
front end of the shaft, then enter this assembly into
position in the housing.
continue to drive the transmission large gear into
position, then locate the sleeve and fit the locking
washer, engaging the tongue with the groove in the
gear. Screw on the locknut and fit the !ocking tab,
locking screw and split pin.
Refitting the Primary Gearbox
1 Locate the primary gearbox and gasket in position,
using the locating studs (Tr/MD 6050) and supporting
the rear end suitably to obtain correct alignment.
Tighten up the bolts and wire the heads.
2 Install the power take-off assembly, belt pulley, clutch
release shaft and fork, main and primary gear levers
as. described in the appropriate sections.
3 Continue to assemble as described in separating the
tractor on pages 115 to 118.
3 Lift out the main upper shaft, gear and shaft pinion,
then continue applying
- - - - -pressure to the centre screw to
complete the removal of the large gear. Remove the
retainer and oil seal, oil baffle and large bearing.
Remove the cup if necessary, also the welsh plug
from the large gear.
Remove the smdl bearing from the end of the upper
shaft, using tool No. Tr/D 7118-A1, slide the
low gear and shaft pinion off the shaft. Withdraw
the large bearing from the shaft, using tool No.
Tr/D 7006.
4 Remove the main gear selector shaft and oil seal by
unscrewing and removing the retaining screw, then
slide the shaft and socket out to the rear and withdraw
the oil seal.
5 If necessary to remove the transmission hand brake
and shaft, drill out the rivet and withdraw the shaft.
To Reassemble the Main Gearbox
0
1 Fit the selector shaft oil seal lip to gearbox, then enter
the gearbox selector shaft and socket into position.
Lock the retainer screw with a wire then fit the
selector fork and lock the retainer screw with wire.
Fig. 165
Removing the Transmission Large Gear
FRONT TRAlVSMISSION-GEARBOX
4
SPECIFICATIONS AND REPAIR DATA
RATIO
Gearbox
Overall
ROAD SPEEDS
800 R.P.M.
1,200 R.P.M.
1,600 R.P.M.
Tyre Size
Tyre Size
Tyre Size
11-36 &
14-30
I
1st Gear
2nd Gear
3rd Gear
4th Gear
5th Gear
6th Gear
Low Reverse
High Reverse
..
M.P.H.
1 .O4
1.46
1.86
2.63
3.66
6.58
1.40
2.52
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
Transmission lower shaft diameter
..
Transmission reverse idler I.D.
..
Wear limit
Reverse idler gear I.D.
..
..
Wear limit
Feverse idler shaft diameter
..
,
.
Wear limit
Upper shaft diameter
..
..
Wear limit
Lower gear pinion I.D.
..
..
&'ear limit
1.872"-1.882"
(47.5-47.8 mm.)
l.745"-1.7465"
(44.3-44.303 mm.)
1.749" (44.45 mm.)
1.124-1.125"
(28.6-28.63 mm.)
1.127" (28.8 mm.)
1.122"-1.223"
(28.55-28.58 mm.)
1.20 (30.5 mm.)
l.743"-1.744"
(44.3-44.33 mm.)
1.741" (44.2 mm.)
1.74.7"-1.751"
(43.4-43.43 mm.)
1.748" (44.4 mm.)
M.P.H.
1.08
1S 2
1.93
2.72
3.80
6.85
1.45
2.61
M.P.H.
1.56
2.19
2.80
3.94
5.49
9.87
2.10
3.77
11-36 &
14-30
11-38
M.P.H.
2.07
2.92
3.73
5.25
7.32
13.16
2.80
5.03
M.P.H.
2.15
3.03
3.87
5.45
7.60
13.7
2.9
5.22
M.P.H.
1.61
2.27
2\90
4.b9
5.70
10.2
2.18
3.92
Primary lower shaft end-float
..
Primary upper shaft and dog endfloat
. . .. .. ..
Main upper shaft and gear end-float
Main lower shaft and gear end-float
Lubrication
Temperature Range
Above 90°F.
..
Summer and Winter
Below
10°F. . .
Below -10°F.
..
+
Oil capacity
..
..
..
..
..
..
..
..
..
..
..
0.010"-0.050"
(.254-1.27 mm.)
0.010"-0.047"
(.254-1. 194 mm.)
0.0102"-0.0352"
(.259-.894 mm.)
0.010"-0.043"
(.254-1.092 mm.)
Grade of Gear Oil
S.A.E. 140
S.A.E. 90
S.A.E. 80
80 Mild E.P. $
loo/; Kerosene
4.5 imp. galls.
(20.4 litres)