sensor LAND ROVER DISCOVERY 1999 Workshop Manual

MANIFOLDS AND EXHAUST SYSTEMS - V8
30-2-18 REPAIRS
Gasket - inlet manifold - upper - With
Secondary Air Injection
$% 30.15.24
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery earth lead.
3.Remove bonnet.

+ EXTERIOR FITTINGS, REPAIRS,
Bonnet.
4.Disconnect multiplug from MAF sensor.
5.Release clip on intake hose and release
harness.
Note: Pre 03 MY air intake hose illustrated.
6.Release and disconnect IACV hose.
7.Loosen clip securing air intake hose to throttle
body.
8.Release 2 clips securing MAF sensor.
9.Release and remove air intake hose.10.Disconnect vacuum hose from air valve.
11.Loosen clip securing air valve hose to air valve.
12.Remove 2 nuts securing air manifold support
bracket to upper inlet manifold.
13.Disconnect 2 air manifold unions from adapters
in cylinder head.
CAUTION: Take care that air manifold pipes
are not damaged during removal of union
nuts.
14.Remove LH air manifold.
15.Disconnect purge valve hose from inlet
manifold.
16.Release purge valve from clips and air control
valve from bracket and lay aside.
17.Disconnect multiplug from IACV.
18.Release clip and disconnect breather hose
from throttle housing.
19.Disconnect multiplug from TP sensor.

MANIFOLDS AND EXHAUST SYSTEMS - V8
30-2-20 REPAIRS
34.Release clip and disconnect IACV hose.
35.Remove 6 bolts securing upper manifold and
remove manifold.
36.Collect upper manifold gasket.
Refit
1.Clean upper and lower inlet manifold mating
faces, dowels and dowel holes.
2.Using a new gasket, position upper inlet
manifold. Fit bolts and, working in a diagonal
sequence, tighten to 22 Nm (16 lbf.ft).
3.Connect IACV hose and secure clip.
4.Connect hose to air valve and tighten clip.
5.Secure plug leads to clips.
6.Fit and tighten nuts securing RH air manifold
support bracket.
7.Align air pipe and coil bracket, fit bolts and
tighten to 8 Nm (6 lbf.ft).
8.Tighten 2 lower bolts securing coil bracket to 8
Nm (6 lbf.ft).
9.Fit bonnet seal.
10.Secure engine harness in bulkhead clips.
11.Connect breather hose to manifold and secure
clip.
12.Connect vacuum hose to inlet manifold.
13.Connect brake servo hose to inlet manifold.
14.Connect throttle and cruise control cables.
15.Adjust throttle cable.

+ ENGINE MANAGEMENT SYSTEM -
V8, ADJUSTMENTS, Cable - throttle.16.Adjust cruise control cable.

+ ENGINE MANAGEMENT SYSTEM -
V8, ADJUSTMENTS, Cable - cruise control.
17.Connect coolant hoses to throttle housing and
secure clips.
18.Connect multiplug to TP sensor.
19.Connect breather hose to throttle housing and
secure with clip.
20.Connect multiplug to IACV.
21.Secure purge valve and air control valve to clips
and bracket.
22.Connect purge hose to manifold.
23.Clean air manifold unions.
24.Apply a small amount of engine oil to top of air
manifold union nuts and around air manifold
pipes.
25.Position air manifold and finger tighten both air
manifold union nuts.
CAUTION: Finger tighten union nuts as far
as possible, damage to air manifold pipes or
adaptors may result if this is not done.
26.Tighten both air manifold union nuts to 25 Nm
(18 lbf.ft).
CAUTION: Ensure that air manifold pipes
are not distorted during tightening
operation.
27.Fit nuts securing air manifold support bracket
and tighten to 25 Nm (18 lbf.ft).
28.Connect hose to air valve and tighten clip.
29.Connect vacuum hose to air valve.
30.Fit air intake hose.
31.Connect multiplug to MAF sensor.
32.Secure harness to clip.
33.Connect battery earth lead.
34.Fit battery cover and secure with fixings.
35.Top up cooling system.

+ MAINTENANCE, PROCEDURES,
Cooling system.
36.Fit bonnet.

+ EXTERIOR FITTINGS, REPAIRS,
Bonnet.

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
37-14 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

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.

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.

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.

TRANSFER BOX - LT230SE
DESCRIPTION AND OPERATION 41-13
Description
General
The LT 230SE transfer box is mounted at the rear of the gearbox and transmits drive via high or low reduction ratios
to the front and rear axles via the propeller shafts. The high/low ratios are 1.211:1 and 3.32:1 respectively.
Transfer boxes fitted to this model have the prefixes 41D and 42D to the unit serial number. Prefix 41D denotes that
the unit is not fitted with interlock whilst 42D denotes that interlock is fitted.
Vehicles up to 03 model year – Whilst similar to LT230Q transfer boxes fitted to other models, the LT230SE transfer
box has certain engineering modifications incorporated which are as follows:
lUprated torque capacity
lModified front and rear output and cross shaft housings
lIntermediate gear bearing pre-load now controlled by a selective, non-collapsible spacer
lSpeedometer drive and driven gears not fitted for this application
lModified high/low sleeve
lModified front output flange and mud shield
lDifferential lock fitted to certain vehicles, but no longer driver operated
lFixed setting of differential lock warning lamp switch on vehicles fitted with differential lock
Vehicles from 03 model year – The LT230SE transfer box is as described above for vehicles up to 03 model year
with the following modifications:
The following items are introduced on vehicles from 03 model year
lRibs added to main casing to reduce operating noise
lRevised machining process for intermediate gears to reduce operating noise
lBearing retaining nut on the differential carrier has patchlock added to the threads
lInterlock solenoid moved from main casing to selector lever assembly
lIntermediate gears modified with machined internal shoulder and bearing circlips deleted
lDriver operated differential lock
lHigh/Low selector shaft fitted with spring assist
lExisting differential lock switch replaced by 2 new switches of improved design with the additional switch installed
adjacent to the existing switch location.
Construction
The transfer box comprises three main assemblies; the main casing, the front output housing and the rear output
housing. Both output housings and all cover plates are sealed to the main casing by sealant; mud and water ingress
being prevented by mud shields located on the output flanges.
Main casing
The main casing carries the mainshaft input gear, the intermediate gears and the differential, together with the high/
low range gears, selector shaft and fork. The front and rear output housings are bolted to either side of the main
casing.
Transmission neutral sensor
A transmission neutral sensor is fitted on automatic gearbox vehicles for North America and Japan. The sensor is
connected to the BCU and is normally in the open position. The sensor provides an earth path for the BCU which then
interprets the signal and activates an audible warning generated by the IDM if neutral is selected on the transfer box
when the ignition is on.
Transfer box interlock solenoid - Automatic gearbox vehicles
An interlock solenoid is fitted for North America and Japan. The solenoid is located on the top of the transfer box main
casing on vehicles up to 03 model year or on the selector lever assembly on vehicles from 03 model year. The
solenoid is connected to the transfer box relay which, in turn, is controlled by the IDM. The purpose of the solenoid is
to prevent neutral being selected on the transfer box when the ignition key is removed, thereby locking the box in
either high or low ratio.

TRANSFER BOX - LT230SE
41-26 REPAIRS
9.Remove handbrake drum retaining screw and
remove drum.
10.Remove 4 bolts from handbrake back plate,
release back plate and tie aside.
11. Models fitted with high/low shift interlock
solenoid: Release interlock solenoid multiplug
and disconnect multiplug from main harness.
12. Models fitted with high/low shift interlock
solenoid: Remove sleeve retaining rings and
remove sleeve from high/low selector cable.
13. If fitted: Release and remove clevis pin
securing differential lock selector cable to
transfer gearbox.14. If fitted: Loosen locknuts securing differential
lock selector cable to differential lock selector
cable abutment bracket.
15. If fitted: Release and remove differential lock
selector cable from differential lock selector
cable abutment bracket.
16.Remove clevis pin securing high/low ratio
selector cable to selector lever, remove 'C' clip
and release outer cable from abutment bracket.
17. Up to 03 Model Year - if fitted: Disconnect 2
Lucars from differential lock switch and
multiplugs from high/low ratio switch and
neutral sensor.
18.Disconnect multiplug from reverse light switch.

TRANSFER BOX - LT230SE
41-28 REPAIRS
28.Remove 4 bolts and nut, remove gearbox RH
mounting.
29.With assistance, remove transfer box from
gearbox.
30.Remove input shaft oil seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Oil seal - input shaft.
Refit
1.Fit new input shaft oil seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Oil seal - input shaft.
2.Clean transfer box to gearbox mating faces.
3.Raise transfer box on jack and align to guide
studs LRT-41-009.
4.Clean transfer box to gearbox bolt threads.
5.Apply sealant, Part No. STC 50552 to bolt and
stud threads.
6.Fit and lightly tighten 2 bolts and nut securing
transfer box to gearbox. If new stud is to be
fitted, apply sealant, Part No. STC 50552 to
stud threads and tighten to 45 Nm (33 lbf.ft).
7.Remove guide studs, fit and lightly tighten
remaining 3 bolts.
8.Tighten bolts and nut by diagonal selection to
45 Nm (33 lbf.ft).
9.Position gearbox RH mounting and tighten
bolts to 85 Nm (63 lbf.ft).
10.Tighten gearbox RH mounting nut to 48 Nm
(35 lbf.ft).
11.Remove 4 bolts securing support plate to
gearbox jack.
12.Remove 4 bolts securing support plate LRT-99-
010 to transfer box and remove plate.
13.Clean bottom plate bolt threads.
14.Apply sealant, Part No. STC 50552 to threads
of 4 bottom plate bolts.
15.Fit 4 bolts securing bottom plate to transfer box
and tighten to 25 Nm (18 lbf.ft).
16.Position breather pipe and secure to bulkhead
clip.
17.Connect multiplug to reverse light switch. 18. Up to 03 Model Year - if fitted : Connect
Lucars to differential lock switch and multiplugs
to high/low ratio switch and neutral sensor.
19. 03 Model Year onwards - if fitted: Connect
differential lock warning lamp multiplugs,
secure harness.
20.Position high/low ratio selector cable and
secure with clevis pin and 'C' clip.
21.Position differential lock selector cable to
differential lock selector cable abutment
bracket and tighten locknuts sufficiently to
retain cable.
22. If fitted: Fit differential lock selector cable to
transfer gearbox and secure with clevis pin.
23. If fitted: Adjust differential lock selector cable.

+ TRANSFER BOX - LT230SE,
ADJUSTMENTS, Cable - selector -
differential lock - adjust.
24. Models fitted with high/low shift interlock
solenoid: Position interlock solenoid harness
to high/low shift cable, fit sleeve around cable
and harness; secure sleeve.
25. Models fitted with high/low shift interlock
solenoid: Connect solenoid multiplug to main
harness and secure multiplug to bracket.
26.Clean handbrake and mating face.
27.Position handbrake back plate and tighten
bolts to 75 Nm (55 lbf.ft).
28.Clean handbrake drum.
29.Fit handbrake drum and tighten retaining
screw.
30.Fit front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
31.Fit rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
32.Clean exhaust silencer and mating face.
33.Position silencer, fit new gasket , connect
mounting rubbers and tighten nuts to 40 Nm
(30 lbf.ft).
34.Refill transfer box with oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
35.Fit front exhaust pipe.

+ MANIFOLDS AND EXHAUST
SYSTEMS - Td5, REPAIRS, Pipe - front.