service LAND ROVER DISCOVERY 1999 Owner's Guide

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.

MANUAL GEARBOX - R380
37-30 OVERHAUL
4.Using tools LRT-37-043, LRT-37-043/2 and
LRT-99-002, press new bearing onto input
shaft.
5.Using tool LRT-99-002 and a suitable mandrel,
fit input shaft outer bearing track to front cover.
6.Fit layshaft bearing track to front cover.
7.Using tool LRT-99-002 and a suitable mandrel,
fit pilot bearing outer track to input shaft.
8.Clean synchroniser hubs, gears and bearings.
9.Position output shaft in protected vice jaws,
output end upwards.
10.Fit 2nd gear bearing, 2nd gear and
synchromesh baulk rings onto output shaft.
11.Position 1st / 2nd synchroniser hub onto output
shaft. Ensure that baulk rings are correctly
located in hub.
12.Position 1st gear synchromesh baulk rings,
needle roller bearing, 1st gear and bearing
collar onto output shaft. Ensure baulk rings are
correctly located in hub.
13.Remove output shaft from vice. 14.Using tool LRT-37-001, LRT-37-044 and
LRT-99-002, press taper bearing onto output
shaft.
15.Using a feeler gauge, check end float of 1st
gear between gear and collar flange:
lNew = 0.05 - 0.20 mm (0.002 - 0.008 in)
lService limit = 0.327 mm (0.012 in)
16.Using a feeler gauge, check end float of 2nd
gear between gear and output shaft flange:
lNew = = 0.04 - 0.21 mm (0.0016 - 0.0083
in)
lService limit = 0.337 mm (0.013 in)

MANUAL GEARBOX - R380
OVERHAUL 37-31
17.Invert output shaft in vise and fit 3rd gear,
bearing, baulk rings, 3rd / 4th synchroniser and
spacer.
18.Remove output shaft from vice.
19.Using tool LRT-99-002 and a suitable mandrel,
press pilot bearing onto output shaft.
20.Check end float of 3rd gear between gear and
flange on output shaft:
lNew = 0.11 - 0.21 mm (0.004 - 0.0083 in)
lService limit = 0.337 mm (0.013 in)
21.Check output shaft and layshaft end float as
follows.
22.The end float setting for both shafts is:
lNew = 0.00 to 0.05 mm (0.0 to - 0.002 in)
lService limit = 0.05 mm (0.002 in) 23.Fit front cover to gearbox case without the oil
seal and tighten bolts by diagonal selection to
25 Nm (18 lbf.ft).
24.Position in vice with front cover facing
downwards.
25.Fit input shaft to gearbox case less 4th gear
baulk ring.
26.Fit output shaft assembly to input shaft.
27.Fit output shaft bearing track and shim to centre
plate.
28.Fit centre plate to gearbox case and secure
using 8 slave bolts.
29.Rotate output shaft to settle bearings.
30.Fit a suitably large ball bearing into end of
output shaft.
31.Position a suitable DTI and zero probe on ball
bearing.
32.Lift output shaft and note DTI reading.
33.If reading is incorrect, dismantle and fit shim to
give correct end float.
34.Repeat above procedure.
35.Repeat procedure for layshaft end float.
36.Remove and discard 6 bolts and remove
gearbox front cover.
37.Fit gearbox selector fork - set.

+ MANUAL GEARBOX - R380,
OVERHAUL, Fork - set - selector shaft.
38.Fit gearbox front cover.

+ MANUAL GEARBOX - R380,
OVERHAUL, Cover - front.

MANUAL GEARBOX - R380
OVERHAUL 37-33
7.Using tool LRT-37-001, LRT-37-044 and
LRT-99-002, press taper bearing onto output
shaft.
8.Check end float of 1st gear using a feeler gauge
between gear and collar flange:
lNew = 0.05 - 0.20 mm (0.002 - 0.008 in)
lService limit = 0.327 mm (0.012 in)
9.Check end float of 2nd gear using a feeler
gauge between gear and output shaft flange:
lNew = 0.04 - 0.21 mm (0.0016 - 0.0083 in)
lService limit = 0.337 mm (0.013 in)10.Invert output shaft in vice and fit 3rd gear,
bearing, baulk rings, 3rd / 4th synchroniser and
spacer.
11.Remove output shaft from vice.
12.Using tool LRT-99-002 and a suitable mandrel
press pilot bearing onto output shaft.
13. Check end float of 3rd gear between gear and
flange on output shaft.
lNew = 0.11 - 0.21 mm (0.004 - 0.0083 in)
lService limit = 0.337 mm (0.013 in)
14.Fit gearbox selector fork set.

+ MANUAL GEARBOX - R380,
OVERHAUL, Fork - set - selector shaft.

MANUAL GEARBOX - R380
37-50 OVERHAUL
Reassembly
1.Clean centre plate and reverse gear
components.
2.Lubricate gearbox components with clean gear
oil.
3.Position idler gear, bearing and spacer to idler
shaft.
4.Using a suitable press fit idler shaft to centre
plate.
5.Using feeler gauges, check clearance between
reverse idler and shaft flange; fit a thicker or
thinner spacer if necessary in order to achieve
correct clearance:
lNew clearance = 0.04 - 0.38 mm (0.002 -
0.015 in)
lService limit = 0.38 mm (0.015 in)
6.Apply sealant, Part No. STC 4404 to gearbox
casing.
7.Fit lower spring and detent ball into centre
plate, retain using a dummy shaft.
8.Align selector shaft pin with slot in centre plate.
9.Fit centre plate and fit 2 off 8x35 mm slave bolts
to retain centre plate in position on gearbox
case; recover dummy shaft.
10.Fit filter to gearbox case.
11.Fit interlock spool to selector shaft.
12.Using new 'O' ring, fit spool retainer and tighten
bolts to 8 Nm (6 lbf.ft).
13.Clean threads of detent plug.
14.Apply sealant, Part No. STC 50552 to threads
of detent plug, fit upper detent ball and spring.
15.Fit detent plug and tighten to 25 Nm (18 lbf.ft).
16.Position reverse gear to layshaft.
17.Position reverse gear complete with bearing,
collar and selective spacer to output shaft.
18.Fit 5th / reverse gear synchroniser.

+ MANUAL GEARBOX - R380,
OVERHAUL, Synchronizer assembly - 5th/
reverse.
Housing - gear selector mechanism
$% 37.16.37.01
Disassembly
1.Remove 4 bolts and remove gear selector
housing.
Reassembly
1.Clean mating faces on selector housing and
gearbox.
2.Apply sealant, STC 4404 to selector housing.
3.Clean selector housing bolt threads.
4.Apply sealant, Part No. STC 50552 to threads
of selector housing bolts, position selector
housing and tighten bolts to 25 Nm (18 lbf.ft)
5.Adjust gear lever bias springs.

+ MANUAL GEARBOX - R380,
ADJUSTMENTS, Spring - gear lever bias.

AUTOMATIC GEARBOX - ZF4HP22 - 24
44-16 DESCRIPTION AND OPERATION
Warning lamps
Warning lamps and selector lever position indication
1Transmission temperature warning lamp (red)
2Gear selector lever position indication3Sport mode warning lamp (green)
4Manual mode warning lamp (green)
Illumination for each warning lamp is provided by a non serviceable LED.

PROPELLER SHAFTS
DESCRIPTION AND OPERATION 47-3
Front propeller shaft
1Hookes joint
2Grease nipple
3Universal joint4Gaiter/Sliding spline joint
5Lubrication point
The front propeller shaft consists of a tube with a universal joint and a sliding spline joint at the front end, and a
Hookes joint at the rear end. The universal joint is bolted to the pinion flange of the front axle differential. The Hookes
joint is bolted to the front output shaft of the transfer box.
The Hookes joint is lubricated during manufacture and sealed for life. A grease nipple is installed in the universal joint
to lubricate the serviceable, sealed needle bearings of the joint. The sliding spline joint is sealed with a gaiter and
lubricated through a lubrication point on the tube. Because of the proximity of a chassis crossmember to the front
propeller shaft, the lubrication point is normally sealed with a grub screw. During maintenance, the grub screw is
temporarily replaced by a slave grease nipple to lubricate the sliding spline joint.

PROPELLER SHAFTS
47-4 DESCRIPTION AND OPERATION
Rear propeller shaft
1Flexible coupling
2Grease nipple
3Universal joint4Gaiter/Sliding spline joint
5Grease nipple
The rear propeller shaft consists of a tube with a universal joint and a sliding spline joint at the front end, and a flexible
coupling bolted to the rear end. The universal joint is bolted to the rear output shaft of the transfer box. The flexible
coupling is bolted to the pinion flange of the rear axle differential.
A grease nipple is installed in the universal joint for lubrication of the serviceable, sealed needle bearings in the joint.
The sliding spline joint is sealed with a gaiter and lubricated through a grease nipple in the tube.

PROPELLER SHAFTS
47-6 REPAIRS
Bush - spigot - rear propeller shaft
$% 47.15.16
Remove
1.Remove rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
2.Clean protruding end of spigot bush fitted to
rear propeller shaft.
3. Fit LRT-47-001/1 to exposed end of spigot
bush at rear of propeller shaft and tighten
draw bar.
4.Fit LRT-99-004 to draw bar of LRT-47-001/1,
tighten and with assistance remove bush from
rear propeller shaft.
5.Remove bush and dismantle service tools.Refit
1.Ensure bush bore is clean.
2.Fit spigot bush to LRT-47-001/02 , ensure
spigot bush sealing ring is facing drive flange
on service tool.
3.Align bush to bore of rear propeller shaft and
with assistance drive fully home. Note: Do not
allow the propeller shaft universal joint to
support the load during fitting.
4.Remove service tool.
5.Lubricate bush.
6.Fit rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.

STEERING
DESCRIPTION AND OPERATION 57-7
Reservoir
1Filler cap
2Reservoir body (dual PAS/ACE shown )
3Filter4Supply connection
5Return connection
The fluid reservoir is made of moulded plastic and is located on LH side of the engine compartment, on a bracket
which is attached to the inner wing. Dependent on the vehicles specification the reservoir may be a dual PAS/ACE,
or PAS only reservoir. Both types of reservoir are similar to each other the dual PAS/ACE reservoir has two chambers,
the PAS only reservoir has one chamber of a larger capacity. On both types of reservoir the PAS chamber has its own
filler cap and is identified by lettering on the reservoir body.
A filter of fine polyester mesh is moulded into the base of the chamber. The filter removes particulate matter from the
fluid before it is drawn into the supply connection and is non-serviceable. Upper and lower level marks are moulded
into the reservoir body, the reservoir is fitted with filler cap, a seal in the cap prevents leakage. The filler cap is pushed
onto a latch and turned through 90° to lock. A breather hole is incorporated in the cap to allow venting of air due to
fluid level changes during operation. The breather hole also allows air that may be in the fluid to separate out and vent
to atmosphere.
The reservoir holds hydraulic fluid and allows for expansion and contraction of the fluid due to temperature variations.
With the reservoir correctly filled the inlet to the PAS pump will be kept covered at normal operational attitudes. The
fluid flowing to the reservoir is cooled by convection from the pipe surfaces, the fluid held in the reservoir also allows
convection from the sides of the reservoir to take place. The total capacity of the reservoir with PAS only is 1000 cc
(0.264 US gallons), for vehicles fitted with PAS and ACE the total capacity of the reservoir is 500 cc (0.132 US
gallons).