CLUTCH - V8
DESCRIPTION AND OPERATION 33-2-7
Flywheel
The flywheel is bolted to a flange on the rear of the crankshaft with six bolts. A dowel on the crankshaft flange ensures
that the flywheel is correctly located. A ring gear is fitted on the outside diameter of the flywheel and seats against a
flange. The ring gear is an interference fit on the flywheel and is installed by heating the ring and cooling the flywheel.
The ring gear is a serviceable item and can be replaced if damaged or worn.
The operating face of the flywheel is machined to provide a smooth surface for the drive plate to engage on. Three
dowels and six threaded holes provide for the location and attachment of the pressure plate. The flywheel is balanced
to ensure that it does not produce vibration when rotating. A machined slot, with a series of holes within the slot, is
located on the engine side of the flywheel. The slot accommodates the tip of the crankshaft position sensor which is
used by the Engine Control Module (ECM) for engine management.
+ ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine
management.
Pressure plate
1Leaf spring
2Fulcrum ring
3Fulcrum ring
4Drive plate
5Pressure plate6Diaphragm
7Cover
8Rivet
9Retractor clip
The pressure plate assembly comprises a pressure plate, cover and diaphragm and is mounted on and rotates with
the flywheel.
CLUTCH - V8
DESCRIPTION AND OPERATION 33-2-9
The drive plate is of the spring centred type and is sandwiched between the pressure plate and the flywheel. The drive
plate has a splined hub which engages with the splines on the primary drive shaft from the gearbox. The hub is located
in an inner plate which contains six compression damper springs. A spring retainer plate and a disc adaptor are
secured together with stop pins which limit the angular deflection of the disc adaptor. Engine power is transmitted from
the disc adaptor to the damper springs. The damper springs then transfer the power to the retainer plate and the hub.
Friction washers are located between the hub, retainer plate and disc adaptor and provide further damping.
A spring steel plate is riveted to the disc adaptor and provides the attachment surface for the drive plate friction
material. The friction material comprises discs which are secured with rivets to each side of the plate. The rivets are
installed through recessed holes in the disc and emerge in recessed holes in the opposite disc. The drive plate is 267
mm (10.5 in) diameter and has a friction material manufactured from APTEC T385.
CLUTCH - V8
33-2-10 DESCRIPTION AND OPERATION
Operation
Hydraulic operation
Refer to illustration.
+ CLUTCH - V8, DESCRIPTION AND OPERATION, Hydraulic operation.
When the clutch pedal is depressed, the master cylinder piston is pushed into the master cylinder. The movement of
the piston pressurises the fluid in the master cylinder, forcing the pressurised fluid into the hydraulic feed pipe to the
slave cylinder. The hydraulic pressure is felt at the slave cylinder piston which moves under the hydraulic force
applied, pushing the clutch release lever via the piston rod.
When the clutch pedal is released, the force applied to the release lever by the fingers of the diaphragm, moves the
release lever, which pushes the slave cylinder piston into the cylinder. The displaced hydraulic fluid is pushed up the
hydraulic feed pipe and returned to the master cylinder.
Mechanism operation
When the clutch pedal is depressed, hydraulic pressure extends the piston and rod in the slave cylinder. The
extension of the piston pushes the rod against the outer end of the release lever which pivots around the ball spigot.
The inner end of the release lever pivots towards the engine applying pressure to the release bearing. The release
bearing slides along the release bearing sleeve and pushes on the fingers of the diaphragm. The diaphragm pivots
about the fulcrum rings in the cover. As the diaphragm is deflected, it removes pressure from the pressure plate. The
pressure plate moves away from the drive plate assisted by the three leaf springs and retractor clips.
The removal of force from the pressure plate on the drive plate reduces the friction between the flywheel, drive plate
and pressure plate. The drive plate slips between the flywheel and the pressure plate preventing rotary movement
being transferred from the flywheel and pressure plate to the primary driveshaft.
When the clutch pedal is released, hydraulic force is removed from the piston in the slave cylinder. This allows the
fingers of the diaphragm to push the release bearing along the release bearing sleeve. The movement of the release
bearing moves the release lever which pivots on the ball spigot, pushing the piston and rod back into the slave
cylinder.
The removal of pressure from the release bearing on the diaphragm, causes the diaphragm to pivot around the
fulcrum rings in the cover. The force applied to the pressure plate from the diaphragm overcomes the force of the leaf
springs and the pressure plate moves towards the drive plate and flywheel.
The pressure plate applies pressure to the drive plate which is pushed against the flywheel. As the clutch pedal is
progressively released, the friction between the drive plate, flywheel and pressure plate increases. The increase in
friction transfers the rotary movement of the flywheel and pressure plate to the drive plate which in turn starts to rotate
the primary driveshaft. When the clutch pedal is released fully, the force applied by the diaphragm to the pressure
plate forces the drive plate onto the flywheel with no slippage.
MANUAL GEARBOX - R380
DESCRIPTION AND OPERATION 37-7
Description
General
The R380 all synchromesh gearbox has five forward speeds and reverse and is mounted in line with the engine. The
clutch bell housing is bolted to the front of the gearbox and the transfer box is mounted at the rear.
Gearbox casings
Gearbox casings consist of a front cover, gearcase, centre plate and extension housing. All casings with the exception
of the front cover are located to each other by dowels and sealed. Gearbox filler/level and drain plugs are located in
the gearcase.
Reverse lamp switch
A reverse lamp switch is inserted into the extension housing. Selection of reverse gear will close the switch allowing
current from fuse 25 to flow through the switch to illuminate the reverse lamps. The switch also provides a feed to the
BCU and the automatic interior mirror - if fitted; the mirror moving to the dimming position.
Gearchange assembly
The gearchange assembly is bolted to the top of the gearcase, the upper gear lever being attached to the lower gear
lever by means of a clamp bolt. The lower gear lever ball is housed in a Railko bush inserted in the gear change
housing, the end of the lever locating in the selector yoke which is attached to the end of the selector shaft. Bias
springs provide a positive return of the gear lever to the neutral position with selection of 1st/2nd and 5th/reverse gears
being against bias spring pressure. Spring loaded detent balls fitted in the centre plate locate in grooves in the selector
shaft to provide positive gear and neutral selection.
Lubrication
Lubrication is by an oil pump located in the extension housing and driven by the layshaft with additional lubrication
being provided by splash. The pump directs oil via a filter and internal drillings in the output shaft to lubricate the
components. On non UK and non European models, provision for oil cooling is by means of a thermostat housed in
a cover bolted to the side of the extension housing. The cover incorporates tappings for connections to an oil cooler.
On UK and European models, the thermostat and cover are replaced by an oil by-pass block.
Internal pressures produced within the gearbox are vented to atmosphere via a plastic breather pipe. The pipe is
attached to the extension housing and is routed across the top of the gearcase and secured at the open end by a clip
attached to the engine cylinder block.
Selector shaft and forks
Selector forks for 1st/2nd, 3rd/4th and 5th/reverse gears are located on a single selector shaft; the 1st/2nd and 3rd/
4th selector forks are inside the main gearcase whilst the 5th/reverse selector fork is inside the extension housing.
Each of the selector forks locates inside its corresponding synchromesh hub.
Synchromesh assemblies
Each synchromesh assembly is located on the output shaft adjacent to its corresponding gears and comprises a
synchromesh ring, hub, slippers and sleeve. The hubs and slippers are retained in the sleeves by means of spring
clips. 1st/2nd and 3rd synchromesh assemblies are fitted with double synchromesh rings whilst 4th, 5th and reverse
assemblies are fitted with single rings.
MANUAL GEARBOX - R380
37-14 REPAIRS
24.Remove clevis pin and 'C' washer securing low
ratio selector cable to lever and release cable
from lever housing.
25.Remove 2 cable ties securing cable to fuel
pipes.
26.Disconnect 2 Lucars from oil temperature
sensor and disconnect reverse lamp switch
multiplug.
27.Remove banjo bolts securing breather pipes
and discard sealing washers. 28.Remove bolt securing breather pipe 'P' clip and
release breather pipes.
29. If fitted: Disconnect 2 Lucars from differential
lock switch, release and disconnect transfer
box neutral sensor multiplug.
30. If fitted: Release harness from 2 retaining
clips.
31.Position container to catch oil spillage
32.Remove 3 bolts securing oil cooling pipe
housing to gearbox, release housing and
discard 'O' rings.
33.Using a second jack support the weight of the
engine.
MANUAL GEARBOX - R380
REPAIRS 37-15
34.Remove 14 bolts securing gearbox to engine.
35.With assistance, remove gearbox from engine.
Refit
1.Clean gearbox to engine mating faces, dowels
and dowel holes.
2.Raise gear gearbox on jack and align to clutch
and engine.
3.Fit bolts securing gearbox to engine and
tighten to 45 Nm (33 lbf.ft).
4.Lubricate and fit new 'O' rings to oil cooling
pipe housing.
5.Position coolant pipe housing, fit bolts and
tighten to 25 Nm (18 lbf.ft).
6. If fitted: Secure harness in retaining clips,
connect Lucars to differential lock warning
switch and multiplug to neutral sensor.
7.Position breather pipes and secure 'P' clip with
bolt.
8.Using new sealing washers fit breather pipe
banjo bolts and tighten to 15 Nm (11 lbf.ft).
9.Connect oil temperature sensor Lucars and
reverse lamp switch multiplug.
10.Position low ratio selector cable to housing and
secure with 'C' washer and clevis pin.
11.Secure cable to fuel pipes with new cable ties.
12.Raise gearbox, ensuring gear change lever is
located in grommet.
13.Fit gearbox mountings and tighten bolts to 85
Nm (63 lbf.ft). 14.Fit nuts to mountings and tighten to 48 Nm (37
lbf.ft).
15.Remove 3 bolts securing support plate to
gearbox.
16.Position clutch slave cylinder and heat shield,
fit bolts and tighten to 25 Nm (18 lbf.ft).
17.Clean handbrake back plate and mating face.
18.Position handbrake back plate, fit bolts and
tighten to 75 Nm (46 lbf.ft).
19.Clean handbrake drum.
20.Fit handbrake drum and tighten retaining
screw.
21.Clean propeller shafts and mating faces.
22.Position propeller shafts, align to marks and
tighten bolts to 47 Nm (35 lbf.ft).
23.Clean exhaust silencer and tail pipe mating
faces.
24.Position silencer and secure on mountings,
using a new gasket align to tail pipe, fit nuts
and tighten to 25 Nm (18 lbf.ft).
25.Position rear cross member, fit bolts and
tighten to 25 Nm (18 lbf.ft).
26.Refill gearbox with oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
27.Refill transfer gearbox oil.
+ MAINTENANCE, PROCEDURES,
Transfer box.
28.Fit front exhaust pipe.
+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Front pipe.
29.Fit gear lever extension, fit clamp bolt and
tighten to 25 Nm (18 lbf.ft).
30.Fit gear lever trim and gear change knob.
31.Connect battery earth lead.
32. Fit battery cover and cooling fan cover and
secure fixings.
MANUAL GEARBOX - R380
37-18 REPAIRS
23.Remove clevis pin and 'C' washer securing low
ratio selector cable to lever and release cable
from lever housing.
24.Remove 2 cable ties securing cable to fuel
pipes.
25.Disconnect 2 Lucars from oil temperature
sensor and disconnect reverse lamp switch
multiplug.
26.Remove banjo bolts securing breather pipes
and discard sealing washers.
27.Remove bolt securing breather pipe 'P' clip and
release breather pipes. 28. If fitted: Disconnect 2 Lucars from differential
lock switch, release and disconnect transfer
box neutral sensor multiplug. Release harness
from 2 retaining clips.
29.Position container to catch oil spillage
30.Remove 2 bolts securing oil cooling pipe
housing to gearbox, release housing and
discard 'O' rings.
CAUTION: Always fit plugs to open
connections to prevent contamination.
31.Using a second jack support the weight of the
engine.
MANUAL GEARBOX - R380
REPAIRS 37-19
32.Remove 8 bolts securing gearbox to engine.
33.With assistance, remove gearbox from engine.
Refit
1.Clean gearbox to engine mating faces, dowels
and dowel holes.
2.With assistance raise gearbox on jack and
align to clutch and engine.
3.Fit bolts securing gearbox to engine and
tighten to 50 Nm (37 lbf.ft).
4.Clean oil cooling pipe housing mating faces.
5.Lubricate and fit new 'O' rings to oil cooling
pipe housing.
6.Position cooling pipe housing, fit bolts and
tighten to 25 Nm (18 lbf.ft).
7. If fitted: Secure harness in retaining clips,
connect Lucars to differential lock warning
switch and multiplug to transfer box neutral
switch.
8.Position breather pipes and secure 'P' clip with
bolt.
9.Using new sealing washers fit breather pipe
banjo bolts and tighten to 15 Nm (11 lbf.ft).
10.Connect oil temperature sensor Lucars and
reverse lamp switch multiplug.
11.Position low ratio selector cable to housing and
secure with 'C' washer and clevis pin.
12.Secure cable to fuel pipes with new cable ties. 13.Raise gearbox, ensuring gear change lever is
located in grommet.
14.Fit gearbox mountings and tighten bolts to 85
Nm (63 lbf.ft).
15.Fit nuts to gearbox mountings and tighten to 48
Nm (37 lbf.ft).
16.Remove 3 bolts securing support plate to
gearbox.
17.Position clutch slave cylinder and heat shield,
fit bolts and tighten to 25 Nm (18 lbf.ft).
18.Clean handbrake back plate and mating face.
19.Position handbrake back plate, fit bolts and
tighten to 75 Nm (55 lbf.ft).
20.Clean handbrake drum.
21.Fit handbrake drum and tighten retaining
screw.
22.Fit front propeller shaft.
+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front..
23.Fit rear propeller shaft.
+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
24.Clean exhaust silencer and tail pipe mating
faces.
25.Position silencer and secure on mountings,
using a new gasket align to tail pipe, fit nuts
and tighten to 25 Nm (18 lbf.ft).
26.Fit exhaust front pipe.
+ MANIFOLDS AND EXHAUST
SYSTEMS - Td5, REPAIRS, Pipe - front.
27.Refit starter motor.
+ CHARGING AND STARTING,
REPAIRS, Starter motor - diesel.
28.Refill gearbox with oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
29.Refill transfer gearbox with oil.
+ MAINTENANCE, PROCEDURES,
Transfer box.
30.Fit gear lever extension, fit clamp bolt and
tighten to 25 Nm (18 lbf.ft).
31.Fit gear lever trim and gear change knob.
32.Connect battery earth lead.
33.Fit cooling fan cowl and battery cover and
secure fixings.