1995 LAND ROVER DISCOVERY change wheel

01INTRODUCTION
4
INFORMATION ACCESSORIES AND CONVERSIONS
DO NOT FITunapproved accessories or conversions,
as they could affect the safety of the vehicle.
Land Rover will not accept liability for death, personal
injury, or damage to property which may occur as a
direct result of the fitting of non-approved conversions
to the vehicle.
WHEELS AND TYRES
WARNING: DO NOT replace the road
wheels with any type other than genuine
Land Rover wheels which are designed for
multi-purpose on and off road use and have very
important relationships with the proper operation
of the suspension system and vehicle handling.
Replacement tyres must be of the make and sizes
recommended for the vehicle, and all tyres must
be the same make, ply rating and tread pattern.
STEAM CLEANING
To prevent consequential rusting, any steam cleaning
within the engine bayMUSTbe followed by careful
re-waxing of the metallic components affected.
Particular attention must be given to the steering
column, engine water pipes, hose clips and ignition
coil clamp.
SPECIFICATION
The specification details and instructions set out in
this Manual apply only to a range of vehicles and not
to any one. For the specification of a particular vehicle
purchasers should consult their Dealer
The Manufacturer reserve the right to vary their
specifications with or without notice, and at such times
and in such manner as they think fit. Major as well as
minor changes may be involved in accordance with
the Manufacturer's policy of constant product
improvement.
Whilst every effort is made to ensure the accuracy of
the particulars contained in this Manual, neither the
Manufacturer or Dealer, by whom this Manual is
supplied, shall in any circumstances be held liable for
any inaccuracy or the consequences thereof.SPECIAL SERVICE TOOLS
The use of approved special service tools is
important. They are essential if service operations are
to be carried out efficiently, and safely. Where special
tools are specified,only these tools should be used
to avoid the possibility of personal injury or
damage to the components.Also the amount of time
which they save can be considerable.
Every special tool is designed with the close
co-operation of Land Rover, and no tool is put into
production which has not been tested and approved
by us. New tools are only introduced where an
operation cannot be satisfactorily carried out using
existing tools or standard equipment. The user is
therefore assured that the tool is necessary and that it
will perform accurately, efficiently and safely.
Special tools bulletins will be issued periodically giving
details of new tools as they are introduced.
All orders and enquiries from the United Kingdom
should be sent direct to V. L. Churchill. Overseas
orders should be placed with the local V. L. Churchill
distributor, where one exists. Countries where there is
no distributor may order direct from:
V. L. Churchill Limited,
PO Box 3,
Daventry, Northants,
England, NN11 4NF.
The tools recommended in this Workshop Manual are
listed in a multi-language illustrated catalogue,
obtainable from:
Messers. V. L. Churchill at the above address,
or from:
Land Rover Merchandising Service,
PO Box 534,
Erdington,
Birmingham, B24 0Q5,
COPYRIGHT
ÓLand Rover 1996
All rights reserved. No part of this publication may be
produced, stored in a retrieval system or transmitted
in any form, electronic, mechanical, recording or other
means without prior written permission of Land Rover.

Tdi
9
DESCRIPTION AND OPERATION OPERATION EDC
Under start up conditions, signals from the crank
speed and water temperature sensors are relayed to
the ECM to control starting fuel quantity and injection
timing. Once the engine has started the ECM initiates
a 'closed loop' monitoring system for fuel quantity,
injector timing and EGR relative to the appropriate
engine operating conditions.
As driver demand increases, signals from the throttle
position sensor are received by the ECM together with
crank speed and position pulses. The ECM signals
the injection pump to adjust fuel quantity and timing
relative to driver demand.
As engine coolant, fuel and air temperature changes
the ECM will correct fuel delivery and injection timing
for more efficient and accurate running. The ECM will
also make corrections for atmospheric pressure on
injection timing and EGR.
Electronic Control Unit (ECM)
The EDC system is controlled by the ECM located in
the drivers footwell on the 'A' post beneath the fascia.
The unit consists of a microprocessor with integrated
circuits and components and is connected to the main
harness by a 55 pin plug.
Inputs to the ECM from engine sensors control start of
injection, injected fuel quantity, fuel cut-off and EGR.
The ECM will also make corrections for engine
coolant, fuel and air temperature and atmospheric
pressure.Injection pump
The injection pump incorporates actuator controlled
injected fuel quantity and solenoid operated timing
which operate in response to ECM signals against
driver demand, engine speed, temperature and boost
pressure.
A fuel cut-off facility and fuel temperature sensor is
incorporated in the pump.
Injection timing sensor
An inductive sensor in No 4 injector body monitors
needle movement. This forms part of a 'closed loop'
system to control start of injection.
The system measures timing, relating the needle
movement signal to crank position (determined by
flywheel pulses from the engine speed sensor).
Air flow sensor
The Air Flow Sensor is mounted on a bracket
attached to the wheel arch valance, and connected by
hose to the air cleaner and turbo charger inlet.
The unit consists of a flap valve airflow sensor which
measures the fresh air flow into the engine. The
sensor informs the ECM and, provided that the other
conditions are met, will implement EGR.
Engine speed sensor
The engine speed sensor is an active inductive sensor
mounted on the flywheel housing. Pulses from the
sensor activated by radial slots in the flywheel give
engine speed and position information to the ECM.

SFI
1
DESCRIPTION AND OPERATION ENGINE MANAGEMENT SYSTEM
Description
The engine management system (EMS) maintains
optimum engine performance over the entire
operating range. The correct amount of fuel is
metered into each cylinder inlet tract and the ignition
timing is adjusted at each spark plug.
The system is controlled by the ENGINE CONTROL
MODULE (ECM) which receives data from sensors
located on and around the engine. From this
information it provides the correct fuel requirements
and ignition timing at all engine loads and speeds.
The fuel injection system uses a hot wire Mass Air
Flow Sensor to calculate the amount of air flowing into
the engine.
The ignition system does not use a distributor. It is a
direct ignition system (DIS), using four double ended
coils. The circuit to each coil is completed by
switching inside the ECM.
The on board diagnostic system detects any faults
which may occur within the EMS. Fault diagnosis
includes failure of all EMS sensors and actuators,
emissions related items, fuel supply and exhaust
systems.
The system incorporates certain default strategies to
enable the vehicle to be driven in case of sensor
failure. This may mean that a fault is not detected by
the driver. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.
A further feature of the system is 'robust
immobilisation'.Crankshaft position sensor (CKP Sensor)
The crankshaft position sensor is the most important
sensor on the engine. It is located in the left hand side
of the flywheel housing and uses a different thickness
of spacer for manual and automatic gearboxes. The
signal it produces informs the ECM:
- the engine is turning
- how fast the engine is turning
- which stage the engine is at in the cycle.
As there is no default strategy, failure of the
crankshaft sensor will result in the engine failing to
start. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.
Camshaft position sensor (CMP Sensor)
The camshaft position sensor is located in the engine
front cover. It produces one pulse every two
revolutions. The signal is used in two areas, injector
timing corrections for fully sequential fuelling and
active knock control.
If the camshaft sensor fails, default operation is to
continue normal ignition timing. The fuel injectors will
be actuated sequentially, timing the injection with
respect to top dead centre. Injection will either be
correct or one revolution out of synchronisation. The
fault is not easily detected by the driver. The fault is
indicated by illumination of the malfunction indicator
light (MIL) on North American specification vehicles.
Mass air flow sensor (MAF Sensor)
The 'hot wire' type mass air flow sensor is mounted
rigidly to the air filter and connected by flexible hose to
the plenum chamber inlet. The sensing element of the
MAF Sensor is a hot wire anenometer consisting of
two wires, a sensing wire which is heated and a
compensating wire which is not heated. Air flows
across the wires cooling the heated one, changing its
resistance. The ECM measures this change in
resistance and calculates the amount of air flowing
into the engine.
As there is no default strategy, failure will result in the
engine starting, and dying when it reaches 550
rev/min, when the ECM detects no MAF Sensor
signal. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.

19FUEL SYSTEM
2
DESCRIPTION AND OPERATION Basic ignition timing
MEMS provides the optimum ignition timing for the
relevant engine speed and load. The speed and
position of the engine is detected by the crankshaft
sensor which is bolted to, and projects through the
engine adapter plate.
The sensor incorporates an armature which runs
adjacent to a reluctor insert in the flywheel, the insert
consisting of 34 poles spaced at 10°intervals, with
two missing poles 180°apart to identify the T.D.C.
positions.
The sensor 'reads' these poles to provide a constant
up-date of engine speed and crankshaft position to
the ECM
The load signal is provided by the manifold absolute
pressure sensor mounted inside the ECM casing
which detects manifold pressure via a hose connected
to the manifold chamber. The sensor converts
pressure variations into graduated electrical signals
which can be read by the ECMIgnition timing compensation
Coolant temperature sensor
When the ECM receives a low engine temperature
signal from the coolant sensor, it provides optimum
driveability and emissions by advancing or retarding
the ignition timing.
Knock sensor
The knock sensor is a capacitive device mounted in
the cylinder block between nos. 2 and 3 cylinders
below the inlet manifold. The sensor monitors noise
and vibration in the engine and passes this
information to the ECM which is able to identify the
characteristics of the knocking and make the
necessary corrections to the ignition timing of
individual cylinders.
Idle speed control
When the throttle pedal is released and the engine is
at idle, the ECM uses the fast response of ignition
timing to assist idle speed control.
When loads are placed on, or removed from the
engine the ECM senses the change in engine speed
and in conjuction with the opening of the throttle disc
by the stepper motor, advances or retards the ignition
timing to maintain the specified idle speed. When load
is removed from the engine and the stepper motor
returns to it's original position, the ignition timing
returns to the idle setting.
NOTE: Due to the sensitivity of this system
the ignition timing will be constantly
changing at idle speed.

REAR AXLE AND FINAL DRIVE
1
OVERHAUL AXLE DIFFERENTIAL ASSEMBLY
Service repair no - 51.15.07.
DISMANTLE
NOTE: Mark differential components so
their original positions relative to other
components is maintained. Bearing caps
must not be interchanged.
1.Remove axle shafts then differential assembly
fom axle.
2.Remove roll pin securing bearing nut locking
fingers to bearing caps. Remove locking fingers.
3.Loosen bearing cap bolts and mark caps for
assembly.
4.Using service tool LRT-54-508, remove bearing
adjusting nuts.
5.Remove bearing cap bolts and bearing caps.
6.Remove crown wheel differential unit and
bearings.
Remove pinion FRONT AXLE DIFFERENTIAL
ONLY
7.Remove pinion flange nut using service tool
LRT-51-003 to restrain flange.
8.Remove washer and pinion drive flange.
9.Remove pinion complete with bearing and outer
bearing shims.
10.Remove pinion flange oil seal, spacer and
bearing.
Remove pinion REAR AXLE DIFFERENTIAL ONLY
7.Remove pinion flange centralizing peg using
service tool LRT-51-008.
8.Remove pinion flange nut using service tool
LRT-51-003 to restrain flange.
9.Remove pinion complete with bearing and outer
bearing shims.
10.Remove pinion flange oil seal and bearing.
11.Using service tool LRT-54-505, remove pinion
head bearing track and shim and drive out outer
bearing of differential housing.

57STEERING
8
FAULT DIAGNOSIS 4. DIRECTIONAL STABILITY
From 1. GENERAL STEERING:
1.Is directional stability concern when vehicle is
towing?
YES - Check towing/vehicle loading parameters
in Owner's Handbook.
NO - go to 3.
2.Is problem resolved?
YES - end
NO - continue.
3.Check condition of rear trailing link/chassis
bushes.
4.Is problem resolved?
YES - end
NO - continue.
5.Check condition of front and rear shock
absorbers. If in doubt change units in pairs, side
to side.
6.Is problem resolved?
YES - end
NO - continue.
7.Check steering damper.
See Steering Damper
8.Is problem resolved?
YES - end
NO - continue.
9.Check wheel balance
10.Is problem resolved?
YES - end
NO - contact local technical office.POWER STEERING FLUID LEAKS
1.Is fluid level correct?
YES - go to 3.
NO - Refill or drain to correct level. Bleed
system, check for leaks.
See Repair,
Power Steering System - Bleed
2.Is problem resolved?
YES - end
NO - continue.
3.Are hoses or joints leaking? Check on full lock
with engine at 2000 rev/min.
YES - loosen and retorque joints.
NO - go to 6.
4.Does leak remain?
YES - change PAS pipe.
NO - end.
5.Does leak remain?
YES - suspect seal in component. Check and
replace as necessary.
NO - end.
6.Is oil escaping from filler cap?
YES - bleed system.
See Repair, Power
Steering System - Bleed
NO - go to 8.
7.Is oil still escaping from filler cap?
YES - go back to 1.
NO - end.
8.Is oil leaking from PAS pump?
YES - go to 10.
NO - continue.
9.Is oil leaking from PAS box?
YES - go to 10.
NO - end.
10.Clean unit, add tracer dye to system. Retest
11.Is oil still leaking?
YES - establish leak point. Repair or replace
unit as necessary.
NO - end.

57STEERING
10
FAULT DIAGNOSIS VISUAL AND SAFETY CHECKS
WARNING: Before taking vehicle out on
the public highway for road test, it is
important that the following basic visual
checks are carried out to ensure that the vehicle
complies with legal requirements.
Tyres and wheel rims
1.Check and adjust tyre pressures.
See
GENERAL SPECIFICATION DATA,
Information, Tyre Pressures
Note that this information refers to standard tyres
fitted as original equipment.
2.Check condition of tyres. Inspect for signs of
uneven wear, damage and feathering. Check
tread depth.
3.Ensure that the tyre make, type and general
condition are common across each axle.
4.Check wheel rims for signs of damage and
excessive run out.
5.Carry out road test.
See Road Test Procedure
ROAD TEST PROCEDURE
General steering/handling problems can usually be
classified into one of the categories listed and ARE
GENERALLY RELATED TO THE AGE, CONDITION
AND USE OF THE VEHICLE.
WARNING: Ensure that all road tests are
conducted by suitably qualified drivers in
a safe and legal manner, and where local
traffic conditions allow.
1.Carry out visual and safety checks.
See Visual
and Safety Checks
Confirm general nature of complaint with customer,
simulating where possible the conditions under which
the problem occurs. Carry out following road test
procedure to establish the problem.2.Steering load assessment - drive at 16 km/h (10
mph). Put 90°turn input into steering wheel,
check self centering. The self centering should
be equal on each lock BUT not necessarily
return to exactly straight ahead without
assistance from the driver.
3.Steering assessment - drive at 64 km/h (40 mph)
on a staight FLAT road (no camber), check for
steering veer. The vehicle should follow a
straight path with NO tendency to follow a
curved path. If vehicle veers towards the kerb,
vehicle may be 'camber sensitive'. A small
amount of veer in direction of camber is
acceptable.
4.Directional stability assessment - drive at 112
km/h (70 mph) or maximum legal speed on a
straight flat road. Carry out a normal lane
change. Vehicle should quickly settle into a new
straight path.
5.Braking assessment (medium effort) - drive at 96
km/h (60 mph) on a straight flat road. Apply
steady medium braking effort, noting any
tendency to veer. Carry out brake test three
times, if a veer is consistently noted carry out a
braking efficiency test on a rolling road.
6.Braking assessment (full effort) - drive at 96
km/h (60 mph) on a straight flat road. Apply full
braking effort, noting any tendency to veer. Carry
out brake test three times, if a veer is
consistently noted carry out a braking efficiency
test on a rolling road.
If the symptom described by the customer is stiff
steering or steering niggle, carry out stiff steering
procedure.
See Stiff Steering Checklist
If not proceed with basic checks and adjustments.
See Visual Check and Basic Adjustments

74WHEELS AND TYRES
2
REPAIR When the indicators appear in two or more adjacent
grooves, at three locations around the tyre, a new tyre
must be fitted.
NOTE: Do not attempt to interchange
tyres, e.g. from front to rear, as tyre wear
produces characteristic patterns
depending on their position. If tyre position is
changed after wear has occured, the performance
of the tyre will be adversely affected.
NOTE: Territorial vehicle regulations
governing tyre wear MUST be adhered to.
WHEELS INSPECTION
Regularly check the condition of the wheels. Replace
any wheel that is bent, cracked, dented or has
excessive runout.
VALVES INSPECTION
Check condition of inflation valve. Replace any valve
that is worn, cracked, loose, or leaking air.TYRE PRESSURES
Maximum tyre life and performance will be
obtained only if tyres are maintained at the correct
pressures.
Tyre pressures must be checked at least once a
month and at least once a week, preferably daily, if
the vehicle is used off road.
The tyre inflation pressure is calculated to give the
vehicle satisfactory ride and steering characteristics
without compromising tyre tread life. For
recommended tyre pressures in all conditions.
See
GENERAL SPECIFICATION DATA, Information,
Wheels and Tyres
American vehicles - A label attached to the inside
edge of the driver's door also provides tyre pressure
information.
Always check tyre inflation pressures using an
accurate gauge and inflate tyres to the
recommended pressures only.
Check and adjust tyre pressuresONLYwhen the
tyres are cold, vehicle parked for three hours or more,
or driven for less than 3.2 km (2 miles) at speeds
below 64 km/h (40 mph). Do not reduce inflation
pressures if the tyres are hot or the vehicle has been
driven for more than 3.2 km (2 miles) at speeds over
64 km/h (40 mph), as pressures can increase by 0.41
bars (6 p.s.i) over cold inflation pressures.
CheckALLtyre pressures including the spare. Refit
the valve caps as they form a positive seal and keep
dust out of the valve.