transmission LAND ROVER DISCOVERY 1995 User Guide

12ENGINE
20
REPAIR CYLINDER HEAD GASKET
Service repair no - 12.29.02
Remove
1.Disconnect battery negative lead.
2.Remove bonnet [Hood].
See CHASSIS AND
BODY, Repair, Bonnet [Hood]
3.Drain coolant.
4.Remove air cleaner assembly.
See FUEL
SYSTEM, Repair, Air Cleaner
5.Detach crankcase ventilation valve and side
breather hose from rocker cover and move to
one side.
6.Remove injection pipes.
7.Disconnect spill rail from fuel injectors.
8.Remove fuel injectors and sealing washers.
Identify each injector to the location from which it
is removed.
See FUEL SYSTEM, Repair,
Injectors
9.Remove inter-connecting harness from glow
plugs.
10.Remove glow plugs.
See FUEL SYSTEM,
Repair, Glow Plugs
11.Remove top hose, radiator to thermostat.
12.Disconnect by-pass hose from thermostat.
13.Disconnect hose, thermostat to water pump.
14.Disconnect water temperature sensor lead.
15.Remove hose inter-cooler to induction manifold.
16.Remove induction manifold.
See MANIFOLD
AND EXHAUST SYSTEM, Repair, Exhaust
Manifold - Tdi
17.Remove exhaust manifold and turbocharger
assembly.
See MANIFOLD AND EXHAUST
SYSTEM, Repair, Exhaust Manifold - Tdi
18.Disconnect heater hose from water pump and
move heater rail aside.
19.Disconnect heater hose from rear of cylinder
head.
20.Remove bolt securing air cleaner mounting
bracket to support strut.
21.Remove bolt securing harness bracket to
cylinder head.
22.Remove rear lifting bracket, this will also release
clips securing transmission and engine breather
pipes and multiplug. Note loose spacer under
clip securing engine breather pipe and multiplug.

V8i
3
FAULT DIAGNOSIS ENGINE STARTING PROBLEMS
Engine fails to crank in park or neutral (Automatic
Transmission)
1.Is battery in good state of charge?
NO -
See INTRODUCTION, Information,
Jump Starting
YES - Continue.
2.Is automatic transmission inhibitor switch faulty
or gear selection linkage incorrectly adjusted?
YES -
See AUTOMATIC GEARBOX, Repair,
Inhibitor Switch
,
NO -
See Electrical Trouble Shooting
Manual.
If problem is not diagnosed repeat tests, starting
at 1.
Engine fails to crank (Manual Transmission)
1.Is battery in good state of charge?
NO -
See INTRODUCTION, Information,
Jump Starting
YES -See Electrical Trouble Shooting
Manual.
If problem is not diagnosed repeat tests, starting
at 1.
Engine cranks but fails to start
1.Is the cranking speed fast enough (120 rpm)?
NO -
See INTRODUCTION, Information,
Jump Starting
If necessary also.See Electrical Trouble
Shooting Manual.
YES - Continue.
2.Is there combustion in any cylinder?
NO -
See ELECTRICAL, Fault diagnosis,
Lucas Constant Energy Ignition
System - V8i See Electrical Trouble
Shooting Manual.
YES - Continue.
3.Are the fuel supply, tank, pump, ventilation and
emission control systems in correct working
order or the fuel contaminated?
NO -
See FUEL SYSTEM, Repair, Fuel
Filter See FUEL SYSTEM, Repair,
Fuel Tank See FUEL SYSTEM, Repair,
Fuel pump and Sender Unit See
EMISSION CONTROL, Description and
operation, Emission control
If problem is not diagnosed repeat tests, starting
at 2.ENGINE RUNNING PROBLEMS
Engine runs at high speed but will not idle (stops)
Engine idle speed erratic Engine starts but stops
immediately
Engine stalls Engine misfires/hesitation
1.Multiport fuel injection.
See Electrical Trouble
Shooting Manual. See ELECTRICAL, Fault
diagnosis, Lucas Constant Energy Ignition
System - V8i
Check brake vacuum connections.See
BRAKES, Description and operation, Brake
Servo Unit
Check heater/ventilation unit vacuum
connections.
See HEATING AND
VENTILATION, Description and operation,
Heating and Ventilation Unit
If problem is not diagnosed continue.
2.Are HT leads correctly routed and clipped?
NO -
See ELECTRICAL, Repair, Distributor
- V8i
YES - Continue.
3.Is fuel supply, tank, pump, ventilation and
emission control systems in correct working
order or the fuel contaminated?
NO -
See FUEL SYSTEM, Repair, Fuel
Filter See FUEL SYSTEM, Repair,
Fuel Tank See FUEL SYSTEM, Repair,
Fuel Pump and Sender Unit See
EMISSION CONTROL, Description and
operation, Emission Control
If problem is not diagnosed repeat tests, starting
at 1.
Engine lacks power/poor performance
1.Is throttle travel restricted or cable incorrectly
adjusted?
YES - Check thickness of carpets.
See FUEL
SYSTEM, Repair, Throttle Cable See
FUEL SYSTEM, Repair, Accelerator
Pedal
NO - Continue.
2.Are the Ignition and Multiport Fuel Injection
systems in order?
NO -
See Electrical Trouble Shooting
Manual.A1 See ELECTRICAL, Fault
diagnosis, Lucas Constant Energy
Ignition System - V8i See
ELECTRICAL, Repair, Distributor - V8i
YES - Continue.

12ENGINE
4
FAULT DIAGNOSIS 3.Are fuel supply, tank, pump, ventilation and
emission control systems in correct working
order or the fuel contaminated?
NO -
See FUEL SYSTEM, Repair, Fuel
Filter See FUEL SYSTEM, Repair,
Fuel Tank See FUEL SYSTEM, Repair,
Fuel Pump and Sender Unit
YES - Suspect valves held open by hydraulic
tappets due to high oil pressure.
See
Engine Oil Pressure Test
4.Is oil pressure high?
YES - Remove oil filter and cooler adaptor and
check pressure relief valve strainer gauze
for blockage and that the relief valve is
not stuck closed.
See Description and
operation, Description
NO - Carry out cylinder compression tests to
determine condition of head gaskets and
valves.
See Cylinder Compression -
Test
5.Are cylinder compressions satisfactory?
NO -
See Repair, Cylinder Heads - Renew
YES - Check brake vacuum connections.See
BRAKES, Description and operation,
Brake Servo Unit
Check heater/ventilation unit vacuum connections.
See HEATING AND VENTILATION, Description and
operation, Heating and Ventilation Unit
If problem is not diagnosed: Continue.
6.Are the brakes binding?
YES - Investigate cause of binding.
NO - Continue.
7.Automatic Transmission only. Is the Torque
Converter and Transmission operating correctly?
Carry out Road test, Static tests and Stall tests
to determine condition of Automatic
transmission.
If problem is not diagnosed: repeat tests starting at 1.Engine backfires into exhaust system
1.Are there any leaking joints/connections or holes
in the exhaust system?
YES -
See MANIFOLD AND EXHAUST
SYSTEM, Repair, Exhaust System
Complete
NO - Continue.
2.Is distributor fitted correctly, HT leads in correct
firing order and routed correctly?
NO -
See ELECTRICAL, Repair, Distributor
- V8i
YES - Continue.
3.Is air fuel ratio correct?
NO - Check multiport fuel injection.
See
Electrical Trouble Shooting Manual.
Check brake vacuum connections.See
BRAKES, Description and operation, Brake
Servo Unit
Check heater/ventilation unit vacuum
connections.
See HEATING AND
VENTILATION, Description and operation,
Heating and Ventilation Unit
Check the crank case and fuel tank ventilation
system.
See EMISSION CONTROL,
Description and operation, Emission Control
YES - Continue.
4.Are cylinder compressions satisfactory?
NO - Carry out compression test to check for
leaking gaskets valves etc.
See
Cylinder Compression - Test
See Repair, Cylinder Heads - Renew
If problem is not diagnosed: repeat tests starting
at 1.

V8i
11
REPAIR FLEXIBLE DRIVE PLATE AND RING GEAR
Service repair no - 12.53.13
Remove
1.Remove transmission.
See AUTOMATIC
GEARBOX, Repair, LT230T Transfer Gearbox
with Automatic Gearbox Assembly - V8i
2.Remove flexible drive plate and ring gear
assembly.
See V8i Overhaul Manual.
Refit
3.Clean all components for reassembly.
4.Fit ring gear and flexible drive plate assembly.
See V8i Overhaul Manual.
5.Fit transmission.CRANKSHAFT REAR OIL SEAL
Service repair no - 12.21.20
1.Automatic transmission, remove drive plate.
See Flexible Drive Plate and Ring Gear
OR manual transmission, remove flywheel.See
Flywheel
2.Remove sump.See Oil Sump
3.Remove rear main bearing cap.
4.Remove cross seals from cap.
5.Remove crankshaft rear oil seal.
6.Clean main bearing cap and oil seal area of
block.
7.Fit new cross seals to bearing cap.
8.Apply Hylomar SQ32M to block as illustrated.
9.Lubricate bearing shell and cross seals using
clean engine oil.
10.Fit bearing cap, do not tighten bolts.
11.Ensure cap is fully home and seated squarely on
the block.

V8i
13
REPAIR
NOTE: Release bolts securing compressor
mounting bracket to engine and remove
bracket to enable temporary lifting eye
ETC 5964 to be fitted. Secure lifting eye to
mounting bracket fixing points with suitable bolts
of equivalent size, pitch and thread. Leave lifting
eye attached until engine is reinstalled in vehicle.
15.Place drain tray underneath vehicle.
16.Disconnect hose from reservoir to power
steering pump. Secure hose end above level of
fluid reservoir to avoid unnecessary loss of fluid.
17.Disconnect power steering pump to power
steering box hose. Seal hose and pump
openings with masking tape to prevent ingress of
dirt. Wipe away any fluid spillage from chassis or
steering box.
18.Disconnect fuel temperature and coolant
temperature sensor multi-plugs.
19.Disconnect leads from coil.
20.Identify each injector multi-plug for re-assembly
and disconnect plugs from injectors.
21.Manoeuvre harness from behind fuel rails and
place to one side clear of engine assembly.
22.Remove two clamps securing gearbox oil cooler
pipes to engine block.
23.Remove engine mounting fixings on both sides
of cylinder block.
24.Fit lifting chains to engine lifting eyes as shown
in illustration RR1780E.
1. L/H Front chain 356mm total overall length.
2. R/H Front chain 330mm total overall length.
3. R/H Rear chain 457mm total overall length.
NOTE: All chain dimensions are measured
from end of lifting hook to end of last link
in chain.
25.Fit chain lifting eye to a suitable engine hoist.
Raise hoist high enough to enable engine
mountings to be removed, and withdraw rubber
mountings.
26.Lower hoist until engine rests securely on engine
mounting brackets. Remove lifting chains and
hoist.
27.Disconnect two heater hoses located on top of
right hand rocker cover.
28.Remove ground strap from rear of left hand
cylinder head. DO NOT remove from retaining
clip.
29.Remove all electrical harnesses from retaining
clips at rear of engine.
30.Remove transmission breather pipes from
retaining clip on rear lifting eye.
31.Remove top two bolts securing bell housing to
cylinder block.
32.Raise front of vehicle, lower vehicle on to axle
stands.
33.Remove bell housing bottom cover. Remove
gasket from bell housing face.
34.Remove nuts securing exhaust downpipes to
manifolds, remove heat shield from right hand
side downpipe.
35.Remove electrical leads from starter motor
solenoid. Disconnect multi-plug from oil level
sensor on side of sump, if fitted.
NOTE: Instructions 37, 38 and 39 refer to
automatic vehicles only.
36.With assistance rotate engine at crankshaft
pulley until two access holes in drive plate/ring
gear assembly are visible.
37.Remove two bolts visible through access holes.
Mark one access hole and one bolt hole to
ensure unit is reassembled in its original position
38.Rotate crankshaft 180Ê until two remaining
access holes are visible, remove two bolts.

4.0 V8
5
REPAIR 77.Release sensor/shield and remove.
78.Disconnect sensor multiplug.
79.Remove sensor.
80.Remove starter motor heatshield.
See
ELECTRICAL, Repair, Starter Motor
Heatshield - 4.0 V8
81.Disconnect solenoid Lucar.
82.Disconnect RH and LH knock sensor multiplugs.
See FUEL SYSTEM SFI, Repair, Knock
Sensor
83.Release harness from engine.
84.Remove nut securing handbrake cable
heatshield.
85.Release speed sensor lead from clip on
heatshield.
86.Remove heatshield.
87.Disconnect top oil cooler pipe union from
transmission.
88.Release union.
89.Remove 'O' ring and discard.
90.Plug pipe and transmission.
91.Remove bolt securing oil cooler pipe bracket tosump. Collect spacer.
92.Remove 3 bolts from top of bell housing.
93.Collect 2 harness brackets.
94.Remove 2 bolts, LH and RH side of bell housing.
95.Remove centre LH bell housing bolt using long
extension.
96.Remove 2 lower bolts from bell housing.
97.Fit suitable wooden block in access plate hole to
retain torque converter.
98.Secure block with cover plate and tighten one
cover plate bolt.
99.Support gearbox on a jack.
100.Lower ramp.
101.Position lifting chains and attach hooks to engine
lifting eyes.
102.Raise engine.
103.Raise jack.
104.Break engine to gearbox joint.
105.Raise engine.

12ENGINE
6
REPAIR
106.Remove top starter bolt securing engine earth
cable.
107.Remove nut securing kick-down cable clip to LH
cylinder head.
108.With assistance, raise engine, move aside all
pipes and wires. Move engine clear of vehicle.
109.Lower engine onto bench.
Refit
110.Clean engine and gearbox mating faces.
111.Clean dowel and dowel holes.
112.With assistance raise engine off bench. Lower
and guide engine into engine compartment
ensuring no wires or pipes become trapped.
113.Position clip securing kick-down cable to LH
cylinder head.
114.Fit and tighten nut.
115.Position engine earth cable and secure to starter
with top bolt. Tighten to
45 Nm.
116.Lower engine.
117.With assistance, engage engine with gearbox.
118.Fit 3 bottom bell housing bolts. Tighten to
46
Nm.
119.Lower jack supporting gearbox.
120.Lower engine onto mounting brackets.
121.Fit centre RH bell housing bolt.
122.Fit centre LH bell housing bolt.
123.Fit harness brackets to 2 top bell housing bolts.
124.Fit bolts. Tighten to
46 Nm.
125.Remove plugs from tranmission and oil cooler
pipe.
126.Clean pipe, lubricate NEW 'O' ring and fit to
pipe.
127.Connect pipe to transmission and secure with
union. Tighten to
30 Nm.
128.Align pipe bracket to sump, position spacer and
fit bolt. Tighten to
18 Nm.
129.Fit heatshield and secure with nut.
130.Secure transducer lead to clip on heatshield.131.Slacken bell housing access plate bolt.
132.Move plate aside.
133.Remove block.
134.Align drive plate and torque converter.
135.Fit 2 torque converter bolts.
136.Rotate engine and fit second 2 bolts. Tighten to
45 Nm.
137.Rotate engine and tighten first 2 bolts to Tighten
to
45 Nm.
138.Clean cover plate and mating face.
139.Position cover plate and fit bolts. Tighten to
45
Nm.
140.Position access plate.
141.Fit 2 remaining bolts and tighten all bolts to
Tighten to
9 Nm.
142.Position engine harness around engine.
143.Connect knock sensor multiplug.
144.Connect starter solenoid Lucar.
145.Position starter motor heatshield and secure clip
to solenoid.
146.Align shield bracket to engine mounting bracket
and fit bolt. Tighten to
9 Nm.
147.Clean crankshaft sensor mating faces.
148.Position sensor and connect multiplug.
149.Position/align sensor and shield to backplate. Fit
bolts. Tighten to
6 Nm.
150.Fit tie bar, align to transmission and fit bolts.
Tighten to
25 Nm.
151.Fit tie bar securing nut. Tighten to45 Nm.
152.Fit catalytic converter/front pipe assembly.See
EMISSION CONTROL, Repair, Catalytic
Converter/Front Pipe - 4.0 V8
153.Raise engine.
154.Fit RH mounting rubber.
155.Move engine over.
156.Fit LH mounting rubber.
157.Lower engine.
158.Disconnect hoist.
159.Fit engine mounting nuts. Tighten to
55 Nm.
160.Remove plugs from steering pump and steering
box.
161.Clean PAS hose unions.
162.Lubricate 'O' rings and fit to hose unions.
163.Position hose.
164.Align unions to pump and steering box. Tighten
14mm thread to
15 Nm, 16mm thread to
Tighten to
20 Nm.
165.Remove plugs from feed hose and PAS pump.
166.Connect hose to pump and tighten clip.
167.Untie compressor and position to engine
bracket.
168.Position heatshield and fit bolts. Tighten to
25
Nm.
169.Connect compressor multiplug.
170.Position drive belt.

19FUEL SYSTEM
10
DESCRIPTION AND OPERATION Vehicle speed sensor
The vehicle speed sensor is located on the transfer
box behind the transmission brake. The unit has a
multirole as the vehicle electronic speedometer
sensor and as a sensor for 'surge damping', (a
function which smooths out engine response to sharp
accelerator movement and reduces vehicle 'bucking').
The sensor is an additional input for engine overheat
protection.
Brake and clutch switches
The brake and clutch switches are located on the
pedal box and serve as safety features to the system.
They return information to the ECM which limits
maximum fuel quantity under braking.
Throttle position sensor
The accelerator pedal is connected directly to a
sensor mounted in the pedal box. Driver demand is
relayed back to the ECM to increase or decrease
injected fuel quantity.
Incorporated in the sensor is a backup idle switch
which the system will default to in the event of sensor
failure.
Boost pressure sensor
The boost pressure sensor is mounted on the
bulkhead. It relays boost pressure information to the
ECM which compensates fuel quantity to reduce
smoke during acceleration.
Electro-pneumatic modulator
The electro-pneumatic modulator is located on the
inner wing just forward of the air cleaner. It regulates
vacuum signals from the source to the EGR valve.
The ECM controls the modulator to open the EGR
valve according to required airflow.Exhaust gas recirculation valve
The EGR valve is located on the engine exhaust
manifold and is controlled by vacuum from the
electro-pneumatic modulator.
Once open the EGR valve directs a quantity of
exhaust gas back into the inlet manifold to be burnt
inside the engine. This reduces NOx (Oxides of
nitrogen) emissions of the engine.
Temperature sensors
Water, Fuel and Air temperature sensors monitor
engine conditions and relay their information back to
the ECM which makes adjustments to injected fuel
quantity, injection timing, EGR and corrections to
measured boost pressure and airflow.

19FUEL SYSTEM
2
FAULT DIAGNOSIS BASE IDLE SPEED SETTING
NOTE: Base idle speed is set at factory. It
should not require further adjustment
unless plenum chamber is changed. The
adjustment screw is sealed with a plug to prevent
unauthorised alteration. Check ignition timing
before attempting following procedure, since this
will affect idle speed.
Equipment required
Two blanking hoses.these are manufactured using
a new air by-pass valve hose - Part No.ETC7874. Cut
two equal pieces 90mm long from hose and seal one
end of each, using 13mm diameter bar. Use a suitable
clamp to ensure an air tight seal.
Checking procedure
1.Drive vehicle at least two miles until engine and
transmission are hot. Switch off engine.
2.Check all electrical loads are OFF, including air
conditioning.
3.Remove air by-pass valve hose.
4.Fit blanking hoses to both plenum chamber and
air by-pass valve. Ensure hoses are securely
fitted to prevent air leaks. Note throttle cable and
cruise control actuator have been omitted from
illustration.5.Start engine and check idle speed is within
limits.
See ENGINE TUNING DATA,
Information, Engine 3.9 v8i
Adjusting base idle speed
6.Drill tamper proof plug and insert a self tapping
screw to enable plug to be extracted.
7.Start engine, adjust idle screw clockwise to
decrease or counter-clockwise to increase idle
speed.
8.Stop engine, remove blanking hoses. Reconnect
hose to plenum.
9.Fit new tamper proof plug.

CRUISE CONTROL
1
DESCRIPTION AND OPERATION CRUISE CONTROL COMPONENT LOCATIONS -
Tdi AUTO EDC
COMPONENT LOCATION
1. Cruise control unit Under LH dash...................................................
2. Engagement (on/off) switch Dash panel....................................
3. Cruise control switch Steering wheel...............................................
4. Rotary coupler Steering wheel.........................................................
5. Vacuum pump Box section under jack.........................................................
6. Brake/vent switch Brake pedal....................................................
7. Vehicle speed sensor Transfer box behind transmission brake..............................................
8. Neutral lock-out relay Behind RH lower 'A' post trim casing..............................................
9. Actuator RH engine compartment...................................................................