Page 329 of 2492
MANUAL GEARBOX
Special notes
GEAR LAYOUTGearboxes:
JB1 5 forward gears
JB3
JC5 1 reverse gear
are fitted with BORG-WARNER synchros.
Special notes on the JB3 gearbox
The JC5 gearbox differs from the
JB3gearbox in
the following ways :
- wider teeth on the gears in 1st, 2nd, 3rd and
4th,
- rings under the gears in 2nd, 3rd and 4th,
- offset dog gears on the idle gears in 1st, 2nd
and 4th,
- a new 65.5 mm diameter 1st and 2nd synchro,
- the use of tapered bearings on the primary and
secondary shafts,
- a guide tube with a double seal on the housing
and clutch shaft which can be removed without
opening the gearbox,
- mechanism and clutch housing reinforced ,
- wider torque teeth on the final drive .To engage reverse gear, lift the locking ring (A)
and move the lever. B.V. JB - JC
21
R1 3 5
24
DI2118
21-4
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MANUAL GEARBOX
Consumables
21
TYPEPACKAGING
Loctite 518
LOCTITE FRENBLOC
(locking and sealing
resin)
24 ml syringe
100 g tube
24 cc bottle
PART NUMBER
77 01 404 452
77 01 394 071
COMPONENT
77 01 421 162Housing assembly faces
Threaded plugs and switches
Bearing plugs
Ends of roll pins on driveshafts
Primary and secondary shaft nuts
5th gear fixed gear and hub
Differential lock drive stud
Clutch shaft splines
Fork pivot
Thrust pad guide
Fork pads
MOLYKOTE BR277 01 421 1451 kg tinClutch
Parts to be systematically replaced
When they have been removed:
- lip seals,
- O rings
- thrust pad guide tubes,
- secondary shaft and differential nuts,
- speedo gear and its pin,
- speedo crown wheel,
- roll pins,
- rings under the gears. JB and JC
RHODORSEAL 5661
Eg : CAF 4/60 THIXO
21-5
Page 331 of 2492
MANUAL GEARBOX
Diagnostic
21
Grinding noise when
engaging a gear
Remove the gearbox
Check the synchro and
the synchro spring of
the faulty gear
Clunking when each gear is
engaged
(after checking clutch)
Remove the gearbox
Check the synchros
and the synchro hubs
Impossible to engage gears
(after checking the clutch)
Check the
adjustment of
the selection
linkage
IncorrectCorrect
Condition
of the parts of
the linkage
CorrectIncorrect
Remove the gearbox
Check the gearbox
locking system
Replace the faulty
parts
Adjust the linkage
Adjust the linkage
Operations to be
carried out
KEY
Check
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MANUAL GEARBOX
Diagnostic
21
Abnormal noises when driving
• Stop the vehicle
• Engine running
• Gear lever in neutral
Check
driveshafts
Check
wheel
bearingsReplace the
driveshafts
Replace the
wheel bearings
CorrectIncorrect
CorrectIncorrect
The noise
stops
Yes
Check the thrust
pad, cable and
plate
Replace the faulty
parts
The noise
stops
Look for the
noise in the
engine
Amount
of clearance
Check the toothed
sector of the clutch
pedal and the
cable
Oil level
YesNo
CorrectIncorrect
No
Look for the noise in
the engine
Remove the gearbox
and repair it
The noise
stops
Yes
No
Clutch fully depressed
Remove the
gearbox and
repair it
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MANUAL GEARBOX
Diagnostic
21
Gears jump out
Check
engine and
gearbox
mountings
Adjust the
linkageTighten the bolts or
replace the
mountings
Remove the gearbox
Check the locking
system of the hubs
and sliding gears
IncorrectCorrect
CorrectIncorrect
Replace the faulty
parts
Adjust the linkage
Gear sticking
Adjust the
control
Check the
parts forming
the control
Remove the gearbox
and check:
- the locking balls
- the forks
- the locking plungers
CorrectIncorrect
Adjust the gearbox
control
IncorrectCorrect
Replace the faulty
parts
Adjust the linkage
21-8
Page 334 of 2492
MANUAL GEARBOX
Gearbox (Removal - Refitting)
REMOVAL
- Put the vehicle on a two post lift.
- Disconnect the battery.
- Remove the front wheels.
- Remove the engine undertray.
- Drain the gearbox.
LEFT HAND SIDE OF THE VEHICLE:
Remove:
- the wheel arch (protection),
- the track rod end using tool T.Av. 476.
SPECIAL TOOLING REQUIRED
B.Vi. 31-01 Set of pins
T.Av. 476 Ball joint extractor
21
Bolts of the rear linkage of the suspended
engine mountings (tie-bar) 6
Bolts for securing battery mounting on body 2
Driveshaft gaiter mounting bolt 2.4
Gearbox mounting bolt 3.5
Gearbox control rod bolt 2.8
Shock absorber base bolt 17
Track rod end nut 3.5
Stub-axle key nut 6
Support mounting bolts 4.5
Wheel bolts 9
Caliper guide bolts 2.7
TIGHTENING TORQUES (in daN.m)
All engines
85965R
Remove:
- the two mounting bolts from the caliper by se-
curing the caliper to the suspension spring to
avoid stretching the pipe,
- the three mounting bolts of the driveshaft gai-
ter.
92122R2
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MANUAL GEARBOX
Gearbox (Removal - Refitting)
- the stub-axle carrier driveshaft assembly by re-
leasing the lower ball joint,
- the sub-frame-side member tie rod (A).
21
All engines
RIGHT HAND SIDE OF THE VEHICLE:
Remove the driveshaft pins using toolB.Vi. 31-01
90130R2
Remove :
- the bolt (1),
- the 2 mounting bolts (2) from the base of the
shock absorber,
Check that the driveshaft rollers cannot be remo-
ved by hand. If this is the case, when refitting,
check that the needles have not fallen into the
gearbox.Remove the bolts from the base of the shock ab-
sorber.
98712R1
Tilt the stub-axle carrier and release the drives-
haft.
Remove the stub-axle carrier driveshaft assembly
by releasing the lower ball joint.
Remove and secure the brake caliper.
Remove the mudguard.
Remove the sub-frame body tie rod.99070R1
91755-1R2
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MANUAL GEARBOX
Gearbox (Removal - Refitting)
21
E and K
engines
REFITTING
Coat the sides of the guide tube and the fork pads
with
MOLYKOTE BR2 grease.
Position the fork on the notches of the clutch
thrust pad.
Connect the engine to the gearbox.
Check that the rings (C) for centring the engine-
gearbox are present and are in the correct posi-
tion.
86308R2
Special notes for E7J - K7M engines
Remove the engine/gearbox assembly from above
(see Workshop Repair Manual Chap. 10).
Once the engine and transmission assembly is sui-
tably clear, remove the bolts from around the
gearbox.
Release the gearbox from the engine by removing
the pin (C).
86415R2
Refit:
- the heat shield,
- the exhaust downpipe.
Refit the other components by carrying out the re-
moval operations in reverse (see Workshop Repair
Manual Chapter 10).
21-11