ECU LAND ROVER DISCOVERY 1995 Service Owner's 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.

Tdi
21
REPAIR 23.Remove rocker cover.
24.Remove nuts and bolts and withdraw rocker
shaft assembly.
25.Remove push rods, store as an identified set to
allow refitment to same location.
26.Remove valve stem caps.
27.Evenly slacken, then remove, bolts retaining
cylinder head to block. Two of the bolts also
secure the air cleaner mounting bracket.
28.Lift off cylinder head and remove gasket.
Refit
29.Ensure face of cylinder block is thoroughly clean.
30.Select new gasket of correct thickness.
CAUTION: Three thicknesses of gasket are
available, different thicknesses are
identified by the number of small holes
punched in the right hand side of the gasket. One
hole identifies the thinnest gasket and three holes
the thickest. When renewing gaskets the gasket
being fitted must be of the same thickness as the
one removed. Therefore if the removed gasket had
two holes punched in the side the replacement
gasket must also have two holes punched in the
side.
31.Place gasket on cylinder block with identification
holes positioned towards rear on right hand side
and side marked TOP uppermost.
32.Clean mating face of cylinder head.
33.Lower cylinder head onto block ensuring correct
location with dowels.

12ENGINE
22
REPAIR
NOTE: Cylinder head retaining bolts can
be used up to a maximum of five times.
34.Lubricate threads of bolts with light oil and fit to
positions illustrated.
Bolt sizes:
M10 x 117mm locations 3, 5, 12, and 13.
M12 x 140mm locations 1, 2, 7, 8, 9, 10, 15, 16, 17,
and 18.
M12 x 100mm locations 4, 6, 11, 14.
35.Tighten bolts so that underside of heads just
make contact with cylinder head.
36.Following the sequence illustrated tighten all
bolts to
40 Nm.
37.Attach degree disc special tool LRT-12-007 to a
power bar.
38.Make a suitable pointer from welding rod and
attach to a bolt screwed into a rocker shaft
securing bolt hole.
39.Tighten all bolts through 60°strictly in sequence
illustrated.
40.Repeat 60°tightening procedure, again strictly in
sequence illustrated.
41.Tighten the ten longer bolts (M12 x 140mm) a
further 20°, again following the sequence
illustrated.
NOTE: Repositioning of the pointer will be
necessary to reach all bolts, the pointer
can be fitted to the rocker shaft securing
studs using two nuts.
CAUTION: The double tightening
procedure must be carried out, on no
account should tightening be performed in
one operation, otherwise damage to the cylinder
head may occur.
42.Fit valve stem caps.
43.Fit push rods to locations from which they were
removed.
44.Fit rocker shaft assembly evenly tightening
securing nuts and bolts to correct torque.
45.Fit rocker cover ensuring oil seal is satisfactory
for continued use.
NOTE: Rocker cover seals can be re-used
up to a maximum of five times.
46.Secure rocker cover with special seal washers
and nuts tightened to correct torque.
47.Refit remainder of items by reversing operations
1 to 22 tightening securing bolts to correct torque
where applicable.

Tdi
23
REPAIR VACUUM PUMP
Service repair no - 70.50.19
Remove
NOTE: To ease pump removal set engine
to T.D.C. on No.1 cylinder.
1.Disconnect battery negative lead.
2.Detach servo hose from vacuum pump.
3.Remove six bolts securing vacuum pump.
4.Detach pump complete with harness bracket.
Note location of bracket for refitting.
Refit
5.Clean mating faces of pump and block.
6.Loosely assemble pump to block with a new
gasket and with harness bracket located under
head of bolt noted during removal.
7.Evenly tighten bolts, to depress pump plunger,
finally tightening to
25 Nm.
8.Connect vacuum hose and secure with clip.
9.Reconnect battery negative lead.GENERATOR
Service repair no - 86.10.02
Remove
1.Disconnect battery negative lead.
2.Remove drive belt.
See Drive Belt Renew
3.Disconnect electrical leads from rear of
generator.
4.Remove securing bolt from bottom of generator.
5.Remove long through bolt from top fixing and
withdraw generator.
Refit
6.Reverse removal procedure.

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.

V8i
5
REPAIR CYLINDER HEADS - RENEW
Service repair no - 12.29.15
1.Remove cylinder heads and gaskets.
See
Cylinder Head Gaskets - Renew
2.Remove spark plugs.
3.Using spring compressor LRT-12-034, remove
seals, valves, collets, springs and caps.
CAUTION: Keep components in fitted
order
4.From left hand cylinder head, remove earth lead
studs.
5.Remove three bolts securing power steering
pump mounting bracket to cylinder head.
6.Remove four bolts securing generator mounting
bracket to cylinder head.
7.Right hand cylinder head, remove rear lifting
bracket.
8.Fit lifting bracket to new right hand cylinder
head.
9.Fit mounting brackets and earth lead studs to
new cylinder head. Tighten bolts to
30 Nm.
10.Regrind valves- refer to engine overhaul
publication
11.Lubricate valve stems, fit valves, springs, and
caps. Fit new inlet and exhaust valve stem seals.
12.Using spring compressor LRT-12-034, compress
springs, fit collets. Tap valve to check correct
collet seating.
13.Fit spark plugs.
14.Fit cylinder heads with new gaskets.
See
Cylinder Head Gaskets - Renew
ROCKER COVER - RIGHT HAND - RENEW
Service repair no - 12.29.41
1.Disconnect battery negative lead.
2.Disconnect purge pipe from charcoal canister at
plenum.
3.Remove breather pipe from rocker cover.
4.Remove coolant pipes from inlet manifold.
5.Remove spark plug leads from plugs and
retaining clips.
6.Remove four rocker cover bolts. Moving fuel
pipes aside, remove rocker cover.
7.Discard rocker cover gasket.
8.Remove plug lead retaining clips from rocker
cover, fit to new rocker cover.
9.Clean and dry rocker cover and cylinder head
mating faces, using Bostik cleaner 6001.
NOTE: Gasket fits one way round only. It
must be fitted accurately, first time.
Subsequent movement will destroy
bonding.
10.Apply Bostik 1775 impact adhesive to rocker
cover seal face and gasket, using a brush to
ensure an even film. Allow adhesive to become
touch dry.

12ENGINE
6
REPAIR 11.Place one end of gasket into cover recess with
edge firmly against recess wall, holding
remainder of gasket clear. Work around cover,
pressing gasket into place ensuring edge firmly
contacts recess wall.
12.Allow cover to stand for thirty minutes before
fitting.
13.Fit rocker cover to cylinder head with four
screws, short screws inboard, tighten to
9 Nm.
14.Position fuel pipes.
15.Fit breather pipe to rocker cover, tighten clip.
16.Fit coolant pipes to inlet manifold, tighten bolts.
17.Fit spark plug leads to plugs and retaining clips.
18.Connect purge pipe from charcoal canister at
plenum, tighten clip.
ROCKER COVER - LEFT HAND - RENEW
Service repair no - 12.29.40
1.Remove air flow sensor.
See FUEL SYSTEM,
Repair, Air Flow Sensor
2.Remove plenum chamber.See FUEL SYSTEM,
Repair, Plenum Chamber
3.Remove dipstick.
4.Remove spark plug leads from plugs and
retaining clips.
5.Disconnect HT lead from coil.
6.Remove generator heat shield securing nut from
rocker cover.
7.Remove air flow meter harness clip.
8.Remove bolt securing dipstick tube clip.
9.Remove four rocker cover bolts, remove rocker
cover.
10.Discard gasket
11.Remove plug lead retaining clips from rocker
cover, fit to new rocker cover.
12.Clean and dry rocker cover and cylinder head
mating faces, using Bostik cleaner 6001.
NOTE: Gasket fits one way round only. It
must be fitted accurately, first time.
Subsequent movement will destroy
bonding.
13.Apply Bostik 1775 impact adhesive to rocker
cover seal face and gasket, using a brush to
ensure an even film. Allow adhesive to become
touch dry, approximately fifteen minutes.
14.Place one end of gasket into cover recess with
edge firmly against recess wall, holding
remainder of gasket clear. Work around cover,
pressing gasket into place ensuring edge firmly
contacts recess wall.
15.Allow cover to stand for thirty minutes before
fitting.
16.Fit rocker cover to cylinder head with four
screws, short screws inboard. Tighten to
9 Nm.
17.Position dipstick tube clip. Fit and tighten bolts.
18.Fit and tighten air flow meter harness clip.
19.Fit generator heat shield to rocker cover.
20.Connect HT lead to coil.
21.Connect spark plug leads to plugs and retaining
clips.
22.Fit dipstick.
23.Fit plenum chamber.
24.Fit air flow meter.

V8i
9
REPAIR FRONT COVER GASKET
Service repair no - 12.65.04
1.Remove crankshaft pulley.
See Crankshaft
Pulley Assembly. Do not remove pulleys
2.Remove water pump pulley.
3.Release distributor cap clips.
4.Release plug leads from plugs and clips.
5.Place cap and leads to one side.
6.Turn engine until No. 1 piston is at T.D.C.
7.Check position of rotor arm.
8.Remove fixings securing power steering pump
bracket to water pump bracket.
9.Remove power steering pump bracket from
water pump.
10.Remove clips securing wiring to generator
tensioner.
11.Disconnect distributor feed wire.
12.Pivot power steering pump away from front
cover, tighten pivot to retain in position.
13.Disconnect vacuum pipe from distributor.
14.Remove water pump bottom hose.
15.Disconnect oil pressure switch.
16.Disconnect heater hose at water pump.
17.Remove generator tensioner from water pump,
move tensioner aside.
18.Mark distributor position to front cover.
19.Remove distributor clamp, remove distributor.
See ELECTRICAL, Repair, Distributor - V8i
20.Remove fixings sump to front cover.
21.Loosen four adjacent sump fixings.
22.Remove generator support strut from front cover,
move strut aside.
23.Loosen remaining front cover fixings and remove
front cover.
24.Remove front cover gasket.Refit
25.Clean timing cover, clean block face.
26.Lightly grease gasket faces.
27.Fit new gasket to block face.
28.Apply hylosil to sump gasket.
29.Clean threads of cover fixing bolts, apply Loctite
372 to threads.
30.Fit timing cover, fit fixing bolts. Tighten to
28
Nm.
31.Fit generator support strut to front cover.
32.Tighten sump to timing cover fixings to
10 Nm.
33.Tighten sump fixings to10 Nm.
34.Lubricate distributor O ring.
35.Fit distributor in position marked.
36.Align oil pump drive, if distributor does not seat
correctly.
37.Fit distributor clamp. Tighten to
20 Nm.
38.Locate generator tensioner on water pump
bracket.
39.Connect heater hose, tighten clip.
40.Connect oil pressure switch.
41.Connect bottom hose, tighten clip.
42.Connect vacuum pipe to distributor.
43.Loosen power steering pump pivot, lower pump.
44.Connect distributor feed wire.
45.Connect wire ties to generator tensioner.
46.Fit power steering pump bracket to water pump.
Tighten to
28 Nm.
47.Fit power steering pump to bracket.
48.Position distributor cap. Fit plug leads to plugs
and clips.
49.Clip distributor cap in position.
50.Fit water pump pulley. Tighten to
10 Nm.
51.Fit crankshaft pulley.See Crankshaft Pulley
Assembly
52.Tension drive belts correctly.
53.Check ignition timing.
54.Refill cooling system.

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.

12ENGINE
14
REPAIR
39.Remove remaining bell housing to cylinder block
bolts.
40.Remove starter motor ground strap from
chassis.
41.Remove stands and lower vehicle.
42.Position hydraulic trolley jack under bell housing
to support gearbox when engine and gearbox
are separated.
43.Fit lifting chains to engine. Carefully raise hoist a
little, ease engine and gearbox apart, steady
engine on hoist.
44.Ensure no components remain that will prevent
engine being removed.
45.Slowly raise engine clear of engine
compartment. Move engine away from vehicle
and place on a suitable engine stand.
Refit
46.Fit lifting chains to engine. Raise engine using
hoist.
47.Lower engine into engine compartment. Ensure
all components are clear of engine assembly.
48.Automatic vehicles: With assistance, manoeuvre
engine until bottom two engine and bellhousing
bolt holes align. Ensure that two cylinder block
dowels locate in bell housing.
Manual vehicles: Lower engine into position.
Locate primary pinion into clutch. Engage bell
housing dowels.
49.Fit two bolts and partially tighten.
50.Remove jack and lower hoist until engine rests
securely on engine mounting brackets.
51.Fit top two bell housing securing bolts. Tighten
to
40 Nm.
52.Fit remaining bell housing to cylinder block bolts.
Tighten to
40 Nm.
53.Automatic vehicles: With assistance, rotate
crankshaft pulley, line up marked holes in drive
plate and torque converter. Fit two bolts.
Tighten to
40 Nm.
54.Rotate crankshaft 180°and fit remaining two
bolts tighten to correct torque,
40 Nm.
55.Fit new gasket and refit bottom cover, tighten
bolts to
9 Nm.
56.Fit new exhaust flange gaskets, fit exhaust to
manifold.
57.Refit all harnesses, ground straps breather pipes
and hoses at rear of engine.
58.Raise engine and refit engine mounting rubbers,
tighten nuts to
20 Nm.
59.Remove temporary lifting eye ETC 5964 and
reverse instructions 1 to 23, ensuring that all
electrical plugs and harnesses are fitted in
correct locations.