1999 LAND ROVER DEFENDER oil type

12ENGINE
16
OVERHAUL 5.Repeat above procedures for remaining rocker
arms.
CAUTION: Keep rocker arms in their fitted
order.Rocker arms and shaft - Inspection
1.Clean rocker arms and shaft, ensure oilways are
clear.
CAUTION: Identify type of rocker shaft
fitted. Engine Serial No. Prefixes 10P to
14P - Type A rocker shaft. Engine Serial
No. Prefixes 15P to 19P - Type B rocker shaft.
Type B rocker arms and shaft may be fitted to
Engine Serial No. Prefixes 10P to 14P as an
assembly.
2.Check diameter of each rocker arm journal on
shaft, take 2 measurements at 180°in centre of
journal.
Journal diameter =26.971 to 26.998 mm
(1.062 to 1.063 in)
CAUTION: Any ovality must be within
limits given.
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ENGINE
17
OVERHAUL
3.Using a vernier, check internal diameter of each
rocker arm, take 2 measurements at 180°.
Rocker arm internal diameter =27.0 to 27.013
mm (1.102 to 1.103 in)
CAUTION: Any ovality must be within
limits given.Rocker shaft - Assembling
1.Fit new spring ring to groove in rocker shaft.
2.Lubricate rocker shaft journals and rocker arms
with engine oil.
3.Fit rocker arm to shaft ensuring that it is in its
original fitted order.
4.Fit new spring ring to retain rocker arm.
5.Repeat above procedures for remaining rocker
arms ensuring they are in their original fitted
order.
6.Fit new rocker adjusting screws and locknuts to
rocker arms; do not tighten screws fully into
arms at this stage.
CAUTION: Ensure screws are correct for
type of rocker arms fitted. Replacement
screws for Engine Serial No. Prefixes 15P
to 19P have a centre punch mark adjacent to the
adjusting slot. These screws are not
interchangeable with those fitted to Engine Serial
No. Prefixes 10P to 14P.
Cylinder head - Assembling
1.Lubricate new valve stem oil seals with engine
oil.
2.Using toolLRT-12-071, fit valve stem oil seals.
3.Lubricate valve guides, valve stems, valve
spring caps and springs with engine oil.
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ENGINE
31
OVERHAUL 8.Remove and discard big-end bearing shell from
connecting rod.
CAUTION: Engine Serial No. Prefixes 10P
to 14P:- The’sputter type’connecting rod
bearings fitted to these engines, identified
by them having a slightly darker colour than the
bearing cap shells should be replaced with the
’plain type’bearing shells fitted to Engine Serial
No. Prefixes 15P to 19P.
9.Repeat above procedures for remaining big-end
bearings.
CAUTION: Keep bearing caps in their fitted
order.
Inspection
NOTE: If crankshaft is to be removed,
big-end bearing journals should be
checked when crankshaft is inspected.
1.Check each big-end bearing journal for scoring,
wear and ovality, make 3 checks at 120°intervals
in centre of journal:
Big-end journal diameter =
54.000±0.01 mm (2.125±0.0004 in)
CAUTION: Big-end journals may not be
reground undersize,only one size of
big-end bearing shell is available and if
journals are found to be scored, oval or worn,
crankshaft must be replaced. Big-end bearing
shells must be replaced whenever they have been
removed.Refit
1.Clean connecting rod journals and bearing shell
locations.
2.Lubricate new big-end bearing shells with engine
oil and fit to connecting rods and bearing caps
ensuring that the’sputter bearings’are fitted to
the connecting rods.
NOTE:’Sputter type’bearing shells can be
identified by them by having a slightly
darker colour.
3.Rotate crankshaft until No. 1 big-end bearing
journal is at BDC.
4.Taking care not to damage oil squirt jet or to
displace bearing shell, pull connecting rod on to
crankshaft journal.
5.Check that bearing shell is correctly located in
big-end bearing cap.
6.Fit No. 1 big-end bearing cap ensuring that
reference marks are aligned.
7.Lightly oil threads of new big-end bearing cap
bolts, fit bolts and tighten to:
Stage 1 -20 Nm (15 lbf.ft)
Stage 2 -Further 80
°
CAUTION: Do not carry out stages 1 and 2
in one operation.
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COOLING SYSTEM
5
DESCRIPTION AND OPERATION A - EU 3 Models
B- Pre EU3 Models
GENERAL
The cooling system used on the Diesel engine is a pressure relief by-pass type system which allows coolant to
circulate around the engine block and heater circuit when the thermostat is closed. With coolant not passing
through the by-pass or the radiator promotes faster heater warm-up which in turn improves passenger comfort.
A coolant pump is mounted on a casting behind the PAS pump and is driven from the PAS pump at crankshaft
speed by the auxiliary drive belt. The pump mounting casting connects with passages in the cylinder block and
pumps coolant from the radiator through the cylinder block.
A viscous fan is attached to an idler pulley at the front of the engine. The fan is attached to a threaded spigot on
the pulley with a right hand threaded nut. The fan draws air through the radiator to assist in cooling when the
vehicle is stationary. The fan rotational speed is controlled relative to the running temperature of the engine by a
thermostatic valve regulated by a bi-metallic coil.
The cooling system uses a 50/50 mix of anti-freeze and water.
Thermostat Housing
A plastic thermostat housing is located behind the radiator. The housing has three connections which locate the
radiator bottom hose, top hose and coolant pump feed pipe. The housing contains a wax element thermostat and
a spring loaded by-pass flow valve.
Thermostat - Main valve
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid
engine warm-up. The thermostat is closed at temperatures below approximately 82°C (179°F). When the coolant
temperature reaches approximately 82°C the thermostat starts to open and is fully open at approximately 96°C
(204°F). In this condition the full flow of coolant is directed through the radiator.
The thermostat is exposed to 90% hot coolant from the engine on one side and 10% cold coolant returning from
the radiator bottom hose on the other side.
Hot coolant from the engine passes from the by-pass pipe through four sensing holes in the flow valve into a tube
surrounding 90% of the thermostat sensitive area. Cold coolant returning from the radiator, cooled by the ambient
air, conducts through 10% of the thermostat sensitive area.
In cold ambient temperatures, the engine temperature is raised approximately 10°C (50°F) to compensate for the
heat loss of 10% exposure to the cold coolant returning from the radiator bottom hose.
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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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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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REAR AXLE AND FINAL DRIVE
1
DESCRIPTION AND OPERATION DESCRIPTION
The welded steel rear axle casing houses a separate
spiral bevel type differential unit, which is off set to the
right of the vehicle centre line. The differential unit
drives the rear wheels via the axle shafts and fully
floating hubs which are mounted on tapered roller
bearings.
Lubrication
The differential is lubricated with oil and the hub
bearings with grease.The hub bearings are fitted with inner and outer seals.
The outer seals prevent the differential oil mixing with
the hub grease and the inner seals prevent dirt
ingress into the hub.
Ventilation
Ventilation of the hub bearings is through the outer oil
seals and the differential ventilation pipe, which
terminates at a high level.
Rear axle hub - 90
1.Axle casing
2.Ventilation pipe
3.Axle shaft
4.Wheel studs and hub
5.Wheel bearing stub axle6.Wheel bearings
7.Inner hub seal
8.Outer hub/axle shaft seal
9.Hub lock plate, thrust washer and nuts
10.Brake disc
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77PANEL REPAIRS
18
SEALING AND CORROSION PROTECTION Seam Sealers
A heat cured, PVC Plastisol sealer is applied to joint
areas during factory assembly. This material is not
suitable for service use.
Carry out seam sealing after the application of primer
and before the surfacer and final paint coats. Ensure
that surfaces are first cleaned of all grease and oil.
Apply the sealer material to the joint as a bead, either
by hand or using an applicator gun. Where necessary,
brush sealer well into the joint and wipe smooth using
a cloth soaked with solvent such as Shell SBP3. This
will ensure an acceptable cosmetic finish.
Apply sealer to ALL accessible joints following repair
work. Be aware that damage to a vehicle can often
result in deflection to those areas of the body which
are remote from the impact. The sealers in these
areas can therefore be disturbed by subsequent
straightening and repair operations. Check joints in
the vicinity of the area undergoing repair for evidence
of cracked sealer, clean them out as required and
re-treat them with fresh sealer using the following
procedure:
Clean the affected joint or seam and
re-treat any exposed metal areas with a
suitable etch phosphate primer.
Treat affected area with an acid-etch
primer.
Apply appropriate seam sealer as
necessary.
Apply appropriate colour coat (and
underbody sealer as applicable).
Where joints are inaccessible following the
reassembly or fitment of components, ensure that a
paste-type sealer is applied to such joints. Certain
seams also become inaccessible after the completion
of panel repairs. In such instances the paint process
should be carried out and sealers applied before final
assembly.Provided access is adequate, apply the sealer to both
sides of the repair joint. Where access is limited to
one side only (e.g. box sections), inject the affected
box member with cavity wax.
CAUTION: ALWAYS deploy an extractor
unit to remove toxic fumes when using
oxy-acetylene equipment to remove panels
treated with wax and sealers.
The following Illustrations show the treatment areas
for Seam Sealing.
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