1999 LAND ROVER DEFENDER gearbox

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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CLUTCH
3
DESCRIPTION AND OPERATION 1.Brake/clutch reservoir
2.Connecting hose
3.Bolt - 2 off
4.Master cylinder
5.Clutch pedal
6.Gearbox housing
7.Primary driveshaft
8.Bolt - 2 off
9.Slave cylinder
10.Bleed nipple
11.Pressure plate
12.Drive plate
13.Dual mass flywheel
14.Metal hydraulic pipe
15.Ball spigot
16.Clutch release bearing sleeve
17.Bolt - 2 off
18.Pivot washer
19.Release lever
20.Release bearing
21.Retaining clip
22.Bolt
23.Plastic hydraulic pipe
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33CLUTCH
6
DESCRIPTION AND OPERATION DESCRIPTION
General
The clutch system is a diaphragm type clutch operated by a hydraulic cylinder. The drive plate is of the rigid centre
type with no integral damping springs. The flywheel is of the dual mass type with damping springs integral with the
flywheel. The clutch requires no adjustment to compensate for wear.
Hydraulic Clutch
The hydraulic clutch comprises a master cylinder, slave cylinder and a hydraulic reservoir. The master and slave
cylinders are connected to each other hydraulically by plastic and metal pipes. The plastic section of the pipe
allows ease of pipe routing and also absorbs engine movements and vibrations.
The master cylinder comprises a body with a central bore. Two ports in the body connect the bore to the hydraulic
feed pipe to the slave cylinder and the fluid reservoir. The bore is also connected to a damper which prevents
engine pulses being transferred hydraulically to the clutch pedal. A piston is fitted in the bore and has an external
rod which is attached to the clutch pedal with a pin. Two coil springs on the clutch pedal reduce the effort required
to depress the pedal.
The master cylinder is mounted on the bulkhead and secured with two bolts. The cylinder is connected to the
shared brake/clutch reservoir on the brake servo by a braided connecting hose.
The slave cylinder is located on the left hand side of the gearbox housing and secured with two bolts. A heat
shield is fitted to protect the underside of the slave cylinder from heat generated from the exhaust system. The
slave cylinder comprises a cylinder with a piston and a rod. A port in the cylinder body provides the attachment for
the hydraulic feed pipe from the master cylinder. A second port is fitted witha bleed nipple used for removing air
from the hydraulic system after servicing. The piston rod locates on a clutch release lever located in the gearbox
housing. The rod is positively retained on the release lever with a clip.
Clutch Mechanism
The clutch mechanism comprises a flywheel, drive plate, pressure plate, release lever and a release bearing. The
clutch mechanism is fully enclosed at the rear of the engine by the gearbox housing.
A clutch release bearing sleeve is attached in the gearbox housing with two bolts and located on two dowels. A
spigot with a ball end is formed on the release bearing sleeve and provides a mounting and pivot point for the
clutch release lever. A dished pivot washer is located on the ball of the spigot. When the release lever is located
on the ball, the pivot washer seats against the rear face of the release lever. A spring clip is located on the lever
and the pivot washer and secures the lever on the spigot. A small bolt retains the spring clip in position.
The release lever is forked at its inner end and locates on the clutch release bearing carrier. The outer end of the
release lever has a nylon seat which locates the slave cylinder piston rod. A second nylon seat, positioned
centrally on the release lever, locates on the ball spigot of the release bearing sleeve and allows the release lever
to pivot freely around the ball.
The clutch release bearing locates on the clutch release lever and release bearing sleeve. The bearing is retained
on a carrier which has two flats to prevent the carrier rotating on the release lever. A clip retains the release lever
on the carrier. The bearing and carrier are not serviceable individually.
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