gearbox LAND ROVER DEFENDER 1999 Owner's Manual

12ENGINE
10
REPAIR Refit
39.Clean mating faces of cylinder head and cylinder
block.
40.Check cylinder head for warping, across centre
and from corner to corner:
Maximum warp = 0.10 mm (0.004 in)
CAUTION: Cylinder heads may not be
refaced, replace cylinder head assembly if
warping exceeds figure given.
41.Ensure coolant and oil passages are clean.
42.Clean dowel holes and fit new dowels.
43.Fit new cylinder head gasket of the correct
thickness with the word’TOP’uppermost.
44.Using assistance, fit cylinder head and locate on
to dowels.
45.Carefully enter new cylinder head bolts together
with their captive washers,DO NOT DROP.
Lightly tighten bolts.
46.Using sequence shown, tighten cylinder head
bolts to:-
Stage 1 -30 Nm (23 lbf.ft)
Stage 2 -65 Nm (48 lbf.ft)
Stage 3 -90°
Stage 4 -Further 180°
Stage 5 -Further 45°
CAUTION: Ensure correct tightening
sequence is followed for all 5 tightening
stages. Do not tighten bolts 315°in one
operation.
47.Fit nut and bolt securing cylinder head to timing
chain cover and tighten to25 Nm (18 lbf.ft).
48.Clean camshaft sprocket and mating face on
camshaft.
49.Ensure engine is set to TDC No. 1 cylinder and
mark on camshaft sprocket is positioned
between the 2 coloured links.
50.Position camshaft sprocket to camshaft, fit and
lightly tighten new bolts then loosen bolts half a
turn.
51.Clean fixed guide retaining pin and apply Loctite
242 to threads.
52.Fit and tighten fixed guide retaining pin to25 Nm
(18 lbf.ft).
53.Clean timing chain tensioner and fit new sealing
washer.
54.Fit timing chain tensioner and tighten to45 Nm
(33 lbf.ft).
55.Tighten camshaft sprocket retaining bolts to36
Nm (27 lbf.ft).
56.RemoveLRT-12-058from camshaft.
57.RemoveLRT-12-158from gearbox bell housing.
58.Clean access plug recess in cylinder head and
fit new’O’ring. Fit access plug.
59.Clean vacuum pump union.
60.Tighten vacuum pipe union to10 Nm (7lbf.ft).
61.Fit bolts securing alternator bracket to cylinder
head and tighten to25 Nm (18 lbf.ft).
62.Connect top hose, heater hoses and secure with
clips.
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ENGINE
17
REPAIR
23.Disconnect oil pressure switch multiplug.
24.Release engine harness from underside of inlet
manifold and tie aside.
25.Release clips and remove coolant top hose from
cylinder head and coolant rail.
26.Remove 4 bolts and move A/C compressor
aside.
27.Remove 3 bolts and remove PAS pump pulley.
28.Remove 4 bolts and move PAS pump aside.
29.Raise vehicle on ramp.
30.Remove 6 bolts securing gearbox housing to
engine.
31.Lower vehicle ramp.
32.Remove 2 upper bolts securing gearbox housing
to engine.
33.Remove bolt securing engine closing panel to
gearbox.
34.Release clip and coolant hose from engine oil
cooler.
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12ENGINE
18
REPAIR
35.Remove 2 bolts and remove acoustic cover from
rear of cylinder head.
36.FitLRT-12-138to suitable lifting chains and
connect to lifting eyes on engine.
37.Remove 2 nuts from RH and LH front engine
mountings.
38.Fit trolley jack to support gearbox.
39.With assistance raise chains and remove engine
from vehicle.Refit
40.With assistance, raise engine from bench and
position in vehicle.
41.With assistance, align engine to gearbox input
shaft.
42.Position 2 upper bolts securing gearbox housing
to engine and tighten to50 Nm (37 lbf.ft).
43.Lower engine onto mountings and tighten nuts to
85 Nm (63 lbf.ft).
44.RemoveLRT-12-138from engine.
45.Fit and tighten bolt securing engine closing panel
to gearbox.
46.Raise vehicle on ramp.
47.Fit bolts securing gearbox housing to engine and
tighten to50 Nm (37 lbf.ft).
48.Lower ramp.
49.Fit acoustic cover to rear of cylinder head and
tighten bolts.
50.Position coolant hose to engine oil cooler and
secure clip.
51.Position PAS pump and tighten bolts to25 Nm
(18 lbf.ft).
52.Position PAS pulley and tighten bolts to25 Nm
(18 lbf.ft).
53.Position A/C compressor and tighten bolts to25
Nm (18 lbf.ft).
54.Route engine harness beneath inlet manifold
and connect multiplugs to oil pressure switch,
A/C compressor, and ECT sensor.
55.Fit and tighten bolts securing engine harness to
camshaft carrier.
56.Connect multiplug to alternator.
57.Connect battery lead to alternator and tighten
nut.
58.Clean CKP sensor and mating face.
CAUTION: If originally fitted:- Fit spacer to
CKP sensor.
59.Using a new’O’ring, fit CKP sensor, tighten bolt
to10 Nm (7 lbf.ft).
60.Connect CKP sensor multiplug.
61.Connect multiplugs to EGR solenoid, inlet
manifold sensor, injector harness, fuel
temperature sensor and CKP sensor.
62.Connect glow plug leads.
63.Connect multiplug to condensor cooling fan.
64.Connect vacuum hose to EGR valve.
65.Connect EGR vacuum hose to vacuum pipe.
66.Position pipe to vacuum pump and secure pipe
to acoustic cover clips.
67.Position fuel cooler. Apply Loctite 242 to bolts
and tighten to18 Nm (13 lbf.ft).
68.Disconnect fuel hose from connector block and
connect to fuel cooler.
69.Connect fuel hoses to fuel cooler and connector
block on cylinder head.
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ENGINE
21
REPAIR Refit
11.Fit mounting and mounting bracket.
12.Fit mounting bracket to cylinder block bolts and
tighten to48 Nm (35 lbf.ft).
13.Fit nuts securing mounting to chassis and tighten
to85 Nm (63 lbf. ft).
14.Fit mounting to mounting bracket nut and tighten
to85 Nm (63 lbf.ft).
15.Remove engine support chains.
16.Position fuel cooler. Apply Loctite 242 to bolts
and tighten to18 Nm (13 lbf.ft).
17.Remove stand(s) and lower vehicle.
18.Reconnect battery negative lead.
19.Fit engine acoustic cover.See this Section.MOUNTING - GEARBOX - REAR - LH
Service repair no - 12.45.07
Remove
1.Raise vehicle on ramp.
2.Position jack to support gearbox.
3.Remove 4 bolts securing mounting bracket to
transfer gearbox.
4.Remove 2 nuts, remove mounting and mounting
bracket.
5.Remove heat shield from mounting.
Refit
6.Clean mounting and mating faces.
7.Position heat shield to mounting.
8.Position mounting and mounting bracket and
tighten nuts to48 Nm (35 lbf.ft)and bolts to85
Nm (63 lbf. ft).
9.Lower support jack.
10.Lower vehicle.
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12ENGINE
22
REPAIR MOUNTING - GEARBOX - REAR - RH
Service repair no - 12.45.09
Remove
1.Remove LH rear gearbox mounting.See this
Section.
2.Remove 4 bolts securing mounting bracket to
transfer gearbox.
3.Remove 2 nuts, remove mounting and mounting
bracket.
Refit
4.Clean mounting and mating faces.
5.Position mounting and mounting bracket and
tighten nuts to48 Nm (35 lbf.ft)and bolts to85
Nm (63 lbf.ft).
6.Fit LH rear gearbox mounting.See this
Section.FLYWHEEL
Service repair no - 12.53.07
Remove
1.Remove clutch assembly.See CLUTCH,
Repair.
2.Remove and discard 8 bolts securing flywheel to
crankshaft and remove flywheel.
NOTE: Dowel located.
Refit
3.Clean flywheel and crankshaft mating face.
4.Position flywheel to crankshaft.
5.Fit new flywheel retaining bolts and tighten by
diagonal selection to:
Stage 1 -40 Nm (30 lbf.ft)
Stage 2 -Further 90°
CAUTION: Do not carry out stages 1 and 2
in one operation.
6.Fit clutch assembly.See CLUTCH, Repair.
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12ENGINE
26
REPAIR
15.Position oil pump drive sprocket and chain on to
oil pump ensuring that the’D’shape on the drive
sprocket is located on flat on the oil pump drive
shaft.
16.Clean oil pump drive sprocket retaining bolt and
apply Loctite 242 to bolt threads.
17.Fit oil pump drive sprocket retaining bolt and
tighten to25 Nm (18 lbf.ft).
18.Fit new sump gasket.See this Section.GASKET - ENGINE TO SUMP
Service repair no - 12.60.38
Remove
1.Remove battery cover.
2.Disconnect battery negative lead.
3.Remove exhaust front pipe.See MANIFOLD
AND EXHAUST SYSTEM, Repair.
4.Drain engine oil.
5.Loosen 4 bolts securing sump to gearbox bell
housing.
6.Remove 2 bolts securing centrifuge drain pipe to
sump and discard gasket.
7.Using sequence shown and noting their fitted
position, remove 20 bolts securing sump.
8.Remove sump, remove and discard gasket.
CAUTION: Do not lever between sump and
cylinder block.
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ENGINE
27
REPAIR Refit
9.Clean sump and mating faces.
10.Apply a bead of sealant, Part No. STC 3254 to
joint faces of timing chain cover and crankshaft
rear oil seal.
11.Position new sump gasket.
CAUTION: Gasket must be fitted dry.
12.Position sump, fit bolts ensuring they are in their
correct fitted position, lightly tighten bolts.
13.Fit bolts securing sump to gearbox bell housing
and tighten to15 Nm (11 lbf.ft).
14.Using sequence shown, tighten sump bolts to25
Nm (18 lbf.ft).
15.Tighten sump to gearbox bell housing bolts to50
Nm (37 lbf ft).
16.Fit new gasket to centrifuge drain pipe and
tighten bolts to10 Nm (7 lbf.ft).
17.Fit exhaust front pipe.See MANIFOLD AND
EXHAUST SYSTEM, Repair.
18.Refill engine with oil.
19.Reconnect battery negative lead.
20.Refit battery cover.
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18ENGINE MANAGEMENT SYSTEM
2
REPAIR SENSOR - CRANKSHAFT SPEED AND POSITION
(CKP)
Service repair no - 18.30.12
Remove
1.Disconnect CKP sensor multiplug.
2.Remove bolt, remove CKP sensor from gearbox
housing and discard’O’ring.
3.If fitted, collect spacer.
Refit
4.Clean gearbox housing and CKP sensor.
5.If fitted, refit spacer.
6.Fit new’O’ring, position CKP sensor to gearbox
housing and tighten bolt to10 Nm (7 lbf.ft).
7.Connect sensor multiplug.
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COOLING SYSTEM
3
DESCRIPTION AND OPERATION
NOTE: Inset A shows differences for Pre
EU3 models
1.Pressure cap
2.Overflow pipe
3.Heater return hose
4.Heater matrix
5.Heater inlet hose
6.Oil cooler return pipe - EU3 models
7.Connecting hose
8.Oil cooler housing assembly
9.Heater inlet pipe
10.Connecting hose
11.Outlet housing
12.Engine Coolant Temperature (ECT) sensor
13.Bleed screw
14.Radiator top hose
15.Radiator - upper
16.Intercooler
17.Gearbox oil cooler
18.Radiator - lower
19.Viscous fan
20.Drain plug
21.Connecting hose
22.Fuel cooler feed hose
23.Radiator bottom hose
24.Thermostat housing
25.Connecting hose
26.Coolant pump feed pipe
27.Coolant by-pass pipe
28.Radiator bleed pipe
29.Connecting hose
30.Coolant pump
31.Fuel cooler
32.Heater/expansion tank return hose
33.Expansion tank
34.EGR Cooler - EU3 models
35.Connecting hose - EU3 models
36.Connecting hose - EU3 models
37.Hose - EGR Cooler to oil cooler return pipe -
EU3 models
38.Radiator lower feed hose - Pre EU3 models
39.Oil cooler return pipe - Pre EU3 models
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COOLING SYSTEM
7
DESCRIPTION AND OPERATION Radiator
The 44 row radiator is located at the front of the vehicle in the engine compartment. The cross flow type radiator is
manufactured from aluminium with moulded plastic end tanks interconnected with tubes. The bottom four rows are
separate from the upper radiator and form the lower radiator for the fuel cooler. Aluminium fins are located
between the tubes and conduct heat from the hot coolant flowing through the tubes, reducing the coolant
temperature as it flows through the radiator. Air intake from the front of the vehicle when moving carries the heat
away from the fins. When the vehicle is stationary, the viscous fan draws air through the radiator fins to prevent
the engine from overheating.
Two connections at the top of the radiator provide for the attachment of the top hose from the outlet housing and
bleed pipe to the expansion tank. Three connections at the bottom of the radiator allow for the attachment of the
bottom hose to the thermostat housing and the return hose from the oil cooler and the feed hose to the fuel cooler.
The bottom four rows of the lower radiator are dedicated to the fuel cooler. The upper of the two connections at
the bottom of the radiator receives coolant from the oil cooler. This is fed through the four rows of the lower
radiator in a dual pass and emerges at the lower connection. The dual pass lowers the coolant temperature by up
to 24°C before being passed to the fuel cooler. Two smaller radiators are located in front of the cooling radiator.
The upper radiator is the intercooler for the air intake system and the lower radiator provides cooling of the
gearbox oil.
Pipes and Hoses
The coolant circuit comprises flexible hoses and metal formed pipes which direct the coolant into and out of the
engine, radiator and heater matrix. Plastic pipes are used for the bleed and overflow pipes to the expansion tank.
A bleed screw is installed in the radiator top hose and is used to bleed air during system filling. A drain plug to
drain the heater and cylinder block circuit of coolant is located on the underside of the coolant pump feed pipe.
Oil Cooler
The oil cooler is located on the left hand side of the engine block behind the oil centrifuge and oil filter. Oil from the
oil pump is passed through a heat exchanger which is surrounded by coolant in a housing on the side of the
engine.
Full water pump flow is directed along the cooler housing which also distributes the flow evenly along the block
into three core holes for cylinder cooling. This cools the engine oil before it is passed into the engine. A small
percentage of the coolant from the oil cooler passes into a metal pipe behind the engine. It then flows into the
lower radiator via a hose.
Fuel Cooler
The fuel cooler is located on the right hand side of the engine and is attached to the inlet manifold. The cooler is
cylindrical in design and has a coolant feed connection at its forward end. A’T’connection at the rear of the cooler
provides a connection for the coolant return from the heater matrix and coolant return from the fuel cooler.
The’T’connection houses a thermostat which opens at approximately 82°C. This prevents the cooler operating in
cold climates. Two quick release couplings on the cooler allow for the connection of the fuel feed from the
pressure regulator and return to the fuel tank. A counter flow system is used within the cooler.
Fuel flows around a coolant jacket within the cooler and flows from the back to the front of the cooler. As the hot
fuel cools travelling slowly forwards it meets progressively colder coolant travelling in the opposite direction
maintaining a differential cooling effect.
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