oil LAND ROVER DISCOVERY 1999 Workshop Manual
[x] Cancel search | Manufacturer: LAND ROVER, Model Year: 1999, Model line: DISCOVERY, Model: LAND ROVER DISCOVERY 1999Pages: 1529, PDF Size: 34.8 MB
Page 461 of 1529

CLUTCH - V8
33-2-6 DESCRIPTION AND OPERATION
Description
General
The clutch system is a conventional diaphragm type clutch operated by a hydraulic cylinder. The clutch requires no
adjustment to compensate for wear.
Hydraulic clutch
The hydraulic clutch comprises a master cylinder, slave cylinder and a hydraulic reservoir, which is also shared with
the braking system. The master and slave cylinders are connected to each other hydraulically by plastic and metal
pipes. The plastic section of the pipe allows ease of pipe routing and also absorbs engine movements and vibrations.
The master cylinder comprises a body with a central bore. Two ports in the body connect the bore to the hydraulic
feed pipe to the slave cylinder and the brake/clutch fluid reservoir. A piston is fitted in the bore and has an external
rod which is attached to the clutch pedal with a pin. Two coiled springs on the clutch pedal reduce the effort required
to depress the pedal.
The master cylinder is mounted on the bulkhead in the engine compartment and secured with two bolts. The cylinder
is connected to the shared brake/clutch reservoir on the brake servo by a braided connecting hose.
The slave cylinder is located on the left hand side of the gearbox housing and secured with two bolts. A heat shield
protects the underside of the cylinder from heat generated from the exhaust system. The slave cylinder comprises a
cylinder with a piston and a rod. A port in the cylinder body provides the attachment for the hydraulic feed pipe from
the master cylinder. A second port is fitted with a bleed nipple for removing air from the hydraulic system after
servicing. The piston rod locates on a clutch release lever located in the gearbox housing. The rod is positively
retained on the release lever with a clip.
Clutch mechanism
The clutch mechanism comprises a flywheel, drive plate, pressure plate, release lever and a release bearing. The
clutch mechanism is fully enclosed at the rear of the engine by the gearbox housing.
A clutch release bearing sleeve is attached in the gearbox housing with two bolts and located on two dowels. A spigot
with a ball end is formed on the release bearing sleeve and provides a mounting and pivot point for the clutch release
lever. A dished pivot washer is located on the ball of the spigot. When the release lever is located on the ball, the pivot
washer seats against the rear face of the release lever. A spring clip is located on the lever and the pivot washer and
secures the lever on the spigot. A small bolt retains the spring clip in position.
The release lever is forked at its inner end and locates on the clutch release bearing carrier. The outer end of the
release lever has a nylon seat which locates the slave cylinder piston rod. A second nylon seat, positioned centrally
on the release lever, locates on the ball spigot of the release bearing sleeve and allows the release lever to pivot freely
around the ball.
The clutch release bearing locates on the clutch release lever and the release bearing sleeve. The bearing is retained
on a carrier which has two flats to prevent the carrier rotating on the release lever. A clip retains the release lever on
the carrier. The bearing and carrier are not serviceable individually.
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.
Page 473 of 1529

MANUAL GEARBOX - R380
37-2 DESCRIPTION AND OPERATION
Gearbox casings, gear change and oil
pump
Page 474 of 1529

MANUAL GEARBOX - R380
DESCRIPTION AND OPERATION 37-3
1Front cover
2Input shaft oil seal
3Oil filler/level plug
4Sealing washer
5Oil drain plug
6Gear case
7Interlock spool retainer, bolt and 'O' ring
8Centre plate
9Locating dowels
10Selector plug, detent balls and spring
11Splash shield and retaining bolt
12Extension housing
13Gate plate and retaining bolt
14Interlock spool retainer, retaining bolt and 'O'
ring – if fitted – extension housing
15Inhibitor cam spring
16Inhibitor cam
17Reverse inhibitor shaft
18Output shaft oil seal
19Oil seal collar
20Oil pump and retaining bolt
21'O' ring
22Reverse lamp switch23Oil by-pass block - UK and European models
24Bolt - oil by-pass block
25'O' ring - oil by-pass block
26Thermostat and housing - non UK and non
European models
27'O' ring - thermostat housing
28Bolt - thermostat housing
29Oil pick-up pipe
30Oil filter
31Oil pick-up ring
32Rubber gaiter
33Cable tie
34Upper gear lever
35Clamp bolt
36Bias springs
37Bolts and washers - bias adjusting plate and
housing
38Bias adjusting plate
39Lower gear lever and ball
40Railko bush
41Oil seal
42Gear change housing
Page 477 of 1529

MANUAL GEARBOX - R380
37-6 DESCRIPTION AND OPERATION
R380 gearbox cross section
1Input shaft
2Breather
3Input shaft 4th gear
4Selector shaft
53rd/4th selector fork
6Output shaft 3rd gear
7Output shaft 2nd gear
81st/2nd selector fork
9Output shaft 1st gear
10Selective shims - output shaft and layshaft end-
float
11Selective shim - reverse gear idler shaft end-
float
125th/reverse selector fork
13Selector yoke14Gear change assembly
15Railko bush
16Output shaft 5th gear
17Output shaft oil seal
18Output shaft
19Oil pump
205th/reverse gear synchromesh assembly
21Output shaft reverse gear
22Centre plate
23Oil filter
241st/2nd synchromesh assembly
25Layshaft
263rd/4th gear synchromesh assembly
27Input shaft oil seal
Page 478 of 1529

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 electrochromic automatic interior mirror - if fitted; the mirror moving from the dimmed position if
applicable.
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.
The gear train
The gear train comprises an input shaft, output shaft, layshaft and reverse idler shaft together with their appropriate
gears and synchromesh assemblies.
The gear train input shaft, output shaft and layshaft are supported by taper roller bearings with all gears on the input
and output shafts running on caged needle roller bearings. Layshaft gears are integral with the shaft with the
exception of reverse/5th gears which are splined to the shaft and retained with a nut. 1st, 2nd, 3rd and 4th gears are
shot peened to improve durability. The reverse idler shaft and gear are supported in the centre plate by a caged
needle roller bearing. End-float of the output shaft and layshaft is controlled by selective shims located in the centre
plate whilst reverse idler shaft end-float is controlled by a selective shim located behind reverse gear.
Page 483 of 1529

MANUAL GEARBOX - R380
37-12 REPAIRS
Gearbox - V8
$% 37.20.02.99
Remove
1.Release turnbuckles and remove battery cover
and cooling fan cowl.
2.Disconnect battery earth lead.
3.Remove gear lever knob and gear lever trim.
4.Remove clamp bolt and remove gear lever
extension. Apply lubricant to gear lever to aid
removal through grommet.
5.Remove front exhaust pipe.
+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Front pipe.
6.Drain gearbox oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.7.Drain transfer gearbox oil.
+ MAINTENANCE, PROCEDURES,
Transfer box.
8.Remove 8 bolts securing rear cross member
and remove cross member.
9.Remove 3 nuts securing intermediate silencer
to tail pipe.
10.Release silencer from mounting rubbers,
remove silencer and discard gasket.
11.Mark front propeller shaft to transfer gearbox
and differential flanges.
Page 485 of 1529

MANUAL GEARBOX - R380
37-14 REPAIRS
22.Lower gearbox sufficiently to access top of
gearbox.
23.Ensure gear lever is released from grommet
and no wires or pipes are trapped when
gearbox is lowered.
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
Page 486 of 1529

MANUAL GEARBOX - R380
REPAIRS 37-15
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.
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.
Page 487 of 1529

MANUAL GEARBOX - R380
37-16 REPAIRS
Gearbox - Diesel
$% 37.20.02.99
Remove
1.Release turn buckles and remove battery cover
and cooling fan cowl.
2.Disconnect battery earth lead.
3.Remove gear lever knob and gear lever trim.
4.Remove clamp bolt and remove gear lever
extension.
5.Apply a little lubricant to gear lever to aid
removal through grommet.
6.Remove exhaust front pipe.
+ MANIFOLDS AND EXHAUST
SYSTEMS - Td5, REPAIRS, Pipe - front.7.Remove starter motor.
+ CHARGING AND STARTING,
REPAIRS, Starter motor - diesel.
8.Drain gearbox oil.
+ MAINTENANCE, PROCEDURES,
Manual gearbox.
9.Drain transfer gearbox oil.
+ MAINTENANCE, PROCEDURES,
Transfer box.
10.Remove 3 nuts securing intermediate silencer
to tail pipe.
11.Release silencer from mounting rubbers,
remove silencer and discard gasket.
12.Remove front propeller shaft.
+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
13.Remove rear propeller shaft.
+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
Page 489 of 1529

MANUAL GEARBOX - R380
37-18 REPAIRS
22.Ensure gear lever is released from grommet
and no wires or pipes are trapped when
gearbox is lowered.
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.