air filter LAND ROVER DISCOVERY 1995 User Guide

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SPECIFICATIONS, TORQUE Turbo charger oil drain adaptor to block 42....................................................
Oil drain pipe to turbocharger 25....................................................................
Turbocharger oil drain pipe to adaptor 38.......................................................
Turbocharger oil feed pipe adaptor to block 25...............................................
Turbocharger oil feed pipe to adaptor 25........................................................
Oil feed pipe to turbocharger 19.....................................................................
Turbocharger to cylinder head (stud) 10.........................................................
Turbocharger to cylinder head (nut) 45...........................................................
Turbocharger to blanking plate 25..................................................................
Turbocharger to EGR valve 25.......................................................................
EGR delivery tube to valve 25........................................................................
EGR delivery tube to mixing tube 25..............................................................
Fuel lift pump to filter (union) 15.....................................................................
Fuel filter from lift pump (banjo bolt) 33...........................................................
Fuel filter to fuel injection pump (banjo bolt) 33..............................................
Fuel injection pump from fuel filter (banjo bolt) 25..........................................
Injector pipes to injectors and fuel injection pump 29.....................................
Spill rail to injectors (banjo bolt) 10.................................................................
Spill rail to injection pump (banjo bolt) 25.......................................................
Boost pipe injection pump (banjo bolt) 10.......................................................
Plug, rear of injection pump 29.......................................................................
PAS pump to mounting plate 25.....................................................................
PAS pump mounting plate to auxiliaries mounting bracket 25........................
PAS pump pulley to hub 25............................................................................
Generator to auxiliaries mounting bracket 25.................................................
Starter motor (bolt and nut) 45........................................................................
Tachometer electrical connection 4...............................................................
Air conditioning compressor
Compressor mounting bracket to front cover 45.............................................
Compressor to mounting bracket (stud) 8......................................................
Compressor to mounting bracket (nut) 25......................................................
Belt tensioner pulley to tensioner arm 45........................................................
Belt tensioner assembly to front cover plate 25..............................................
Idler pulley to front cover plate 45...................................................................
Compressor belt guard (nut) 25......................................................................
Sensors to water outlet elbow (air/con) 25......................................................
Blanking plug, water outlet elbow (air/con) 25................................................
Generator mounting bracket to front cover 45................................................
Generator to mounting bracket 85..................................................................
Generator pulley to hub 95.............................................................................
Generator belt guard 25..................................................................................

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DESCRIPTION AND OPERATION
1. Cylinder heads (2)
2. Rocker covers (2)
3. PCV filter
4. Rocker shafts (2)
5. Hydraulic tappets (8)
6. Pushrods (8)
7. Rocker brackets (8)
8. Rocker arms (4) left and (4) right
9. Rocker shaft springs (6)
10. Inlet manifold
11. Plenum chamber lower
12. Ram pipes (8)13. Plenum chamber upper
14. PCV air intake filter
15. Oil filler
16. Thermostat
17. Thermostat cover
18. Inlet valve seal, spring, cap and collets (8)
19. Exhaust valve seal, spring, cap and collets (8)
20. Inlet valve and seat (8)
21. Exhaust valve and seat (8)
22. Inlet manifold gasket and seals
23. Cylinder head gaskets (2)
24. Valve guides (16)

12ENGINE
2
FAULT DIAGNOSIS ENGINE NOISES
Excessive or obtrusive noise from the engine
compartment originates from three main sources:
A. The exhaust system, which makes an
unmistakable and easy to diagnose noise.
B. External components emit the greatest variety of
noises, but are also easy to diagnose by simply
removing the drive belt.
C. Engine internal mechanical noises which can
vary in volume and pitch and may be a
combination of, tapping - knocking or rumbling,
are the most difficult to diagnose. The following
is therefore a guide to diagnosis of engine
internal mechanical noises only.
Engine internal mechanical noises.
Single or multiple, light tapping noise, particularly
when engine is cold.
See Description and
operation, Description
1.Is engine oil level correct?
NO - Top up to correct level.
See
LUBRICANTS, FLUIDS AND
CAPACITIES, Information,
Recommended Lubricants and Fluids
YES - Continue.
2.Is the lubricating pressure correct?
NO -
See Engine Oil Pressure Test
YES - Suspect valve operating mechanism.
3.To confirm diagnosis, remove the rocker covers
and with the engine idling, insert a feeler gauge
of 0,015mm between each rocker and valve
stem. A faulty valve operating mechanism will
emit a different noise when the feeler gauge is
inserted.
See Repair, Rocker Shaft Renew
Heavy knocking noise (particularly on load and
when engine is hot).
See Description and
operation, Description
1.Is engine oil level correct?
NO - Top up to correct level.
See
LUBRICANTS, FLUIDS AND
CAPACITIES, Information,
Recommended Lubricants and Fluids
YES - Continue.
2.Is the lubricating pressure correct?
NO -
See Engine Oil Pressure Test
YES - Drain engine oil and filter, and examine
for metallic contamination.
3.Is the oil contaminated with metal particles?
YES - Suspect faulty big end bearings. To
confirm diagnosis, short out the ignition to
each spark plug in turn. The noise will
disappear or be reduced when the
cylinder with the faulty big end is shorted
out.
4.If noise is not conclusively diagnosed, check the
security of the flywheel and crankshaft front
pulley. Temporarily release the drive belt to
reduce general noise level and use a
stethoscope to locate source of noise.
Heavy rumbling noise (particularly during hard
acceleration).
See Description and operation,
Description
1.Is engine oil level correct?
NO - Top up to correct level.
See
LUBRICANTS, FLUIDS AND
CAPACITIES, Information,
Recommended Lubricants and Fluids
YES - Continue.
2.Is the lubricating pressure correct?
NO -
See Engine Oil Pressure Test
YES - Drain engine oil and filter, and examine
for metallic contamination.
3.Is the oil contaminated with metal particles?
YES - Suspect faulty main bearings. If noise is
not conclusively diagnosed, check the
security of the flywheel and crankshaft
front pulley. Temporarily release the drive
belt to reduce general noise level and use
a stethoscope to locate source of noise.

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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.

EMISSION CONTROL
1
DESCRIPTION AND OPERATION REV: 09/95 EMISSION CONTROL
Three systems are used to control the vehicle
atmospheric emissions these are:
Engine crankcase fume emissions.
Fuel tank Evaporative emissions
Engine exhaust gas emissions.
Crankcase ventilation system - 3.9 MFi models
only
The crankcase ventilation system which is an integral
part of the air supply to the engine combustion
chambers, is often overlooked when diagnosing
problems associated with engine performance. A
blocked ventilation pipe or filter or excessive air leak
into the inlet system through a damaged pipe or
leaking gasket can effect the mixture, performance
and economy of the engine.
1. Three way connector
2. Air filter
3. Oil separatorThe purpose of the crankcase ventilation system is to
ensure that any noxious gas generated in the engine
crankcase is rendered harmless by burning in the
combustion chambers as follows:
Oil laden noxious gas in the engine crankcase is
drawn through an oil separator 3 located on the right
cylinder head rocker cover, where the oil is separated
and returned to the sump. The gas flows through a
restrictor in the three way connection 1 and into the
inlet plenum chamber where it is drawn into the
combustion chambers and burned. The volume of
fresh air which is drawn from the atmospheric side of
the throttle butterfly to mix with the gas, depends on
the position of the throttle and the engine speed.
The air filter 2 fitted to the left cylinder head rocker
cover, must be maintained in clean condition to
ensure sufficient air enters the crankcase under
varying throttle openings and manifold depression, to
prevent excessive crankcase pressure or depression
developing.

17EMISSION CONTROL
8
DESCRIPTION AND OPERATION ADD: 09/95 System operation
The system is designed to prevent fuel vapour
escaping to atmosphere, and consists of four roll-over
valves fitted internally in the fuel tank, connected to
the liquid/vapour separator by a nylon line. The
separator is mounted to the side of the filler neck. An
EVAP canister is positioned in the engine
compartment mounted on the right front side valance.
The liquid/vapour separator and EVAP canister are
connected by a nylon line which runs the length of the
chassis.
Pressure/vacuum relief valves are incorporated into
the fuel filler cap and are designed to protect the fuel
tank from permanent deformation in the event of
system pressure or vacuum exceeding the system
operating parameters. There are no other relief or
one-way valves in the system.
A vent line flow restrictor known as an anti-trickle fill
valve is fitted to the filler pipe in the line between the
tank and EVAP canister. The function of this valve is
to prevent overfilling the tank by trickling fuel in,
thereby preserving the vapour space in the tank to
allow for fuel expansion during hot weather.
The valve achieves this by blocking the vent line
during the fuel filling process. The valve is operated
by the action of inserting the filler gun so that when
the fuel in the tank reaches the level of the filling
breather, flow cut off occurs due to fuel filling the filler
pipe.During normal vehicle operation and when the engine
is switched off, the venting system between the fuel
tank and EVAP canister is open to allow the free
passage of vapour.
The EVAP canister, which is connected by a nylon
hose to the plenum chamber, absorbs and stores the
fuel vapour from the fuel tank when the engine is not
running. With the engine running, vapour is purged
from the EVAP canister by allowing outside air to be
drawn through the EVAP canister vent solenoid and
link pipe by the influence of manifold vacuum to the
EVAP canister purge connection on the canister.
Filter pads are fitted above and below the charcoal
and in the EVAP canister vent solenoid to prevent the
ingress of foreign matter into the purge line.
The EVAP canister purge valve, which is fitted in the
line from the EVAP canister to the plenum, is
controlled by the ECM which determines the most
emission acceptable time at which purging should
take place. This will normally be at engine speeds
above idle and when the vehicle is in motion.
The EVAP canister vent solenoid is mounted on the
side of the EVAP canister bracket and is connected to
the EVAP canister by a length of large bore hose. The
ECVS is controlled by the ECM and is normally open.
The function of the ECVS is to block the air intake
side of the EVAP canister. When the system receives
an ECM signal the valve closes; this allows the
system leak check to take place. The leak check only
occurs when pre-determined vehicle operating
conditions are met.

EMISSION CONTROL
1
REPAIR POSITIVE CRANKCASE VENTILATION AIR
INTAKE FILTER
Service repair no - 17.10.02
The PCV air intake filter is located at the rear of the
left hand rocker cover, beneath the throttle linkage
bracket.
Remove
1.Pry the filter outer cover upwards to release it
from its mounting.
2.Remove the sponge filter from the cover and
discard the sponge.
Refit
3.Insert a new filter into the filter cover.
4.Press the filter onto its mounting until it clips
firmly into position.POSITIVE CRANKCASE VENTILATION BREATHER
FILTER
Service repair no - 17.10.03
Remove
1.Release the hose clamp and pull the hose off the
canister.
2.Unscrew the canister and remove it from the
rocker cover.
3.Remove the large rubber 'O' ring and inspect for
deterioration.
4.Visually inspect the condition of the wire screen
within the canister, if in poor condition, replace
the whole assembly, if the filter unit is in an
acceptable condition, clean as follows.
5.Immerse the canister in a small amount of
solvent (mineral spirits) and allow time for the
solvent to dissolve or loosen any debris.
6.Remove the canister from the solvent bath and
allow to dry in still air.
WARNING: Do not use a compressed air
line to dry, clean or remove any remaining
particles of debris within the canister as
this could cause fire or personal injury.
Refit
7.If the original canister is being refitted, fit a new
'O' ring.
8.Screw the canister into the rocker cover securely
- hand tight only.
9.Refit the hose and tighten the hose clamp
securely.

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DESCRIPTION AND OPERATION DESCRIPTION
Air intake
The air cleaner is positioned to the right of the engine
and connected by hoses to a cold air intake duct and
the turbocharger inlet. A crankcase breather hose is
fitted between the air cleaner and the separator.
A single stage turbocharger, fitted between the
exhaust manifold and exhaust pipe, is connected by
hoses to the air cleaner and to an intercooler mounted
on the right of the radiator. The intercooler is
connected by a hose to the inlet manifold.
Fuel system
A 89 litre fuel tank is mounted at the rear of the
vehicle beneath the load space floor. The tank is
vented by a 2 way valve in the filler cap.
A mechanical lift pump, driven by the camshaft, is
mounted on the side of the engine.
A fuel filter, fitted with a replaceable element and
incorporating a water separator, is positioned on the
LH side of the bulkhead.
A Bosch Type injection pump, incorporating a cold
start advance unit and a high idle setting is mounted
on the LH side of the engine and is directly driven by
gears from the crankshaft. The pump meters and
distributes fuel to 4 pintle type injectors located in
pre-combustion chambers in the cylinder heads.
A return line passes excess fuel from the injection
pump and injectors back to the fuel tank.
Glow plugs
Four glow plugs are located in the cylinder head,
directly below each injector.Exhaust gas recirculation (EGR)
Exhaust gas recirculation is controlled by the EGR
control unit mounted in the passenger compartment
on the RH 'A' post behind the fascia and receives the
following inputs:
a. Engine temperature from coolant temperature
transmitter in No. 4 cylinder head.
b. Throttle position from the sensor on the injection
pump.
c. Engine speed from the tachometer.
d. EGR valve lift position.
When all correct signals are received, the EGR
solenoid allows vacuum to open the EGR valve and
recirculate a portion of the exhaust gas.

19FUEL SYSTEM
2
DESCRIPTION AND OPERATION FUEL SYSTEM LAYOUT
1. Fuel tank
2. Fuel lift pump
3. Fuel filter
4. Fuel injection pump
5. Spill return line
6. Fuel injectors
7. Sediment plug
FUEL SYSTEM COMPONENT LOCATION
1. Fuel filter bleed screw
2. Fuel filter
3. Turbocharger
4. Wastegate
5. Air cleaner
6. Fuel injector
7. Glow plug
8. Glow plug controller
9. EGR valve and valve lift position sensor
10. Coolant temperature transmitter - EGR and instruments
11. Fuel injection pump
12. EGR throttle position sensor
13. Fuel lift pump
14. Intercooler
15. EGR Control unit