1999 LAND ROVER DEFENDER ECU

12ENGINE
26
DESCRIPTION AND OPERATION Fuel connector block
Type A - Non EU3 Models - Engine Serial No. Prefixes 10P to 14P
Type B - EU3 Models - Engine Serial No. Prefixes 15P to 19P
1.Fuel connector block assembly
2.Outlet stub pipe
3.Stub pipe - to fuel cooler4.Fuel temperature sensor
5.Fuel pressure regulator
6.Spill return fuel connection (EU3 models only)
A cast and machined aluminium alloy fuel connector block assembly is located at the rear RH side of the cylinder
head, attached by three flanged bolts. A metal gasket is used to seal the faces between the fuel connector block
and the cylinder head, which must be replaced every time the fuel connector block is removed.
CAUTION: The cylinder head incorporates drillings for the fuel injection system, any
contamination which enters these drillings could cause engine running problems or injector
failure. It is therefore, essential that absolute cleanliness is maintained when carrying out work on
the cylinder head.
CAUTION: The valve heads, tips of the injectors and glow plugs protrude below the face of the
cylinder head and will be damaged if the cylinder head is stored face down.
Camshaft carrier
The cast aluminium alloy camshaft carrier is bolted to the cylinder head by thirteen screws. The camshaft carrier
and cylinder head assembly is attached to the cylinder block by twelve cylinder head retaining bolts which pass
through the camshaft carrier and the cylinder head to secure the assembly to the cylinder block.
The carrier is machined together with the cylinder head to form a matched pair for carrying the camshaft.
Non-return valve
A non-return valve is located at the front, bottom LH side of the cylinder head. The non-return valve prevents oil
from draining from the lash adjusters and is an integral component within the cylinder head and is
non-serviceable.
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12ENGINE
28
DESCRIPTION AND OPERATION Inlet and exhaust valves
The inlet and exhaust valves are mounted directly above the engine block cylinders.
Each valve is a forged and ground solid one-piece head and stem which is hardened by heat treatment. The
stems are chrome-plated then ground for improved heat transfer, wear resistance and smooth operation. It is not
possible to recut the valve’s face angle, but the valves can be lapped to their seats using grinding paste.
The valve springs are made from spring steel and are of the parallel single-coil type. The bottom end of the spring
rests on the flange of a spring seal which has a centre bore that locates on a recess ground into the lower valve
stem. The top end of the spring is held in place by a spring cap which is held in position at the top end of the valve
stem by split taper collets. The taper collets have grooves on the internal bore that locate in grooves ground into
the upper stems of the valves.
The valve seats and valve guides are sintered and are an interference fit into the cylinder head. The valve seats
and guides are non-serviceable.
Finger followers and lash adjusters
1.Valve stem
2.Finger follower
3.Lash adjuster plunger4.Oil supply hole
5.Lash adjuster body
The valves are operated through finger followers and lash adjusters, actuated by the camshaft lobes. When the
camshaft lobe presses down on the top of a finger follower roller mechanism, the respective valve is forced down
opening the inlet or exhaust port.
The lash adjuster body contains a plunger and two chambers for oil feed and pressurised oil. Pressurised oil is
supplied to the lash adjusters via the oil galleries in the cylinder head and through a hole in the side of the lash
adjuster body. The oil passes into a feed chamber in the lash adjuster then through to a separate pressure
chamber via a one way ball valve. Oil flow from the pressure chamber is determined by the amount of clearance
between the lash adjuster outer body and the centre plunger, oil escapes up the side of the plunger every time the
lash adjuster is operated, the downward pressure on the plunger forcing a corresponding amount of oil in the lash
adjuster body to be displaced. When the downward pressure from the camshaft and finger follower is removed
(i.e. after the trailing flank of the camshaft lobe has passed), oil pressure forces the lash adjuster’s plunger up
again. This pressure is not sufficient to effect the valve operation, but eliminates the clearance between the finger
follower and top of the valve stem.
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12ENGINE
30
DESCRIPTION AND OPERATION CAMSHAFT COVER COMPONENTS
The camshaft cover cover components are described below:
Camshaft cover
The camshaft cover is cast from aluminium alloy and is fixed to the camshaft carrier / cylinder head assembly by
thirteen bolts. The cover has spacers and sealing washers inserted into each of the thirteen bolt holes.
A breather hose is connected to a port at the top of the camshaft cover by means of a hose clip which vents
crankcase gases back to the air intake via a breather valve in the air intake tract, located forward of the
turbocharger in the flexible air intake duct.
A rubber seal is fitted between the camshaft cover and camshaft carrier.
An oil filler aperture is included in the top of the camshaft cover, which is sealed with a plastic cap with integral
rubber seal.
CAMSHAFT TIMING CHAIN COMPONENTS
The timing chain cover and timing chain components are described below:
Timing chain cover
The timing chain cover is cast and machined aluminium alloy and is attached to the cylinder head by a bolt at the
RH top of the cover and by a stud and nut at the LH top of the cover. Eight screws are used to attach the timing
chain cover to the front of the engine block. The timing cover is located to the cylinder block front face by two
dowels.
A viscous fan is attached to an idler pulley at the front of the engine block. The fan bearing is located on a shaft
and held in place by a circlip and a bearing flange, the inner race of the fan bearing is an interference fit on the
shaft. The fan idler pulley is attached to the bearing hub by three bolts and the fan itself is secured to the pulley
and bearing shaft by a left-hand threaded nut.
The front of the crankshaft passes through a hole in the lower part of the timing cover. An oil seal is pressed into a
recess in the front of the timing cover to seal the interface between the front of the crankshaft and the timing
cover.
A stub pipe is fitted to the front RH side of the timing cover which is used to attach the oil drain pipe from the
vacuum pump by means of a hose and spring clip.
Timing chains
The timing chain between the camshaft and crankshaft sprockets is a duplex type, each chain having 56 links.
The timing chain is contained between a fixed plastic guide and an hydraulically adjustable plastic tensioner arm
which are attached to the front of the engine block.
To cope with the higher injection loads of the EU3 engine, the timing drive between the camshaft and crankshaft
has been upgraded. This requires thicker chain links to be used, therefore the individual pre EU3 and EU3
components are not interchangeable.
To distinguish between the two timing chains the links are different colours. A pre EU3 chain has blue links. An
EU3 chain has bronze links.
The oil pump timing chain is a single type and traverses the oil pump sprocket and the rear crankshaft sprocket.
The timing chains are oil lubricated, with oil being provided by a chain lubrication jet and from oil flow returning
back to the sump from the cylinder head. An oil hole is included at the front left hand side of the cylinder head
which supplies oil from the cylinder head oil galleries.
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ENGINE
1
REPAIR CAMSHAFT
Service repair no - 12.13.02
Remove
1.Remove cylinder head gasket.See this
Section.
2.Note the gasket thickness indicator and ensure
the same thickness gasket is used on refitment
of cylinder head.
3.Disconnect multiplug from injector units and
remove harness from camshaft carrier.
4.Remove and discard multiplug’O’ring.
5.Loosen lock nuts and fully retract rocker
adjusting screws.
6.Progressively loosen then remove and discard 6
bolts securing rocker shaft, remove shaft.
7.Using sequence shown, progressively loosen
then remove 13 bolts securing camshaft carrier
to cylinder head.
8.Gently tap the camshaft carrier upwards to break
the sealant bond and remove carrier noting it is
located by 2 dowels.
9.Remove camshaft.
10.Remove and discard camshaft rear oil seal.
11.Remove and discard lock nuts and rocker
adjusting screws.
12.Check bearing surfaces in cylinder head and
camshaft carrier for signs of scoring and wear.
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ENGINE
3
REPAIR
25.Using sequence shown, progressively tighten
bolts to25 Nm (18 lbf.ft).
26.Lubricate a new camshaft rear oil seal with
engine oil, fit seal using a suitable mandrel.
27.Fit rocker shaft ensuring it is located on dowel, fit
new bolts and working from the centre outwards,
tighten bolts progressively to32 Nm (24 lbf.ft).
28.Fit new’O’ring to injector harness multiplug, fit
harness and connect injector multiplugs.
29.Fit cylinder head gasket.See this Section.
30.Before refitting the camshaft cover the fuel
injector rockers must be adjusted.
31.Rotate engine clockwise until No. 1 injector lobe
is at full lift.
32.Rotate rocker adjusting screw clockwise until the
injector plunger is felt to bottom out.
33.Rotate rocker adjusting screw anti-clockwise 1
complete turn to give plunger the required bump
clearance and tighten rocker adjusting screw
locknut to16 Nm (12 lbf.ft).
34.Carry out above procedure for the remaining 4
rockers.
35.After completion of rocker adjustment, slowly
rotate engine clockwise 2 complete turns by
hand to ensure that no injectors are bottoming
out on their plungers.PULLEY - CRANKSHAFT
Service repair no - 12.21.01
Remove
1.Remove underbelly panel.See CHASSIS AND
BODY, Repair.
2.Remove radiator.See COOLING SYSTEM,
Repair.
3.Using a 15 mm ring spanner release the
auxiliary drive belt tensioner.
4.Remove auxiliary drive belt.
5.Remove 3 bolts and remove crankshaft damper.
6.PositionLRT-51-003to crankshaft pulley and
secure with 2 bolts.
7.Remove and discard crankshaft pulley bolt.
Remove crankshaft pulley.
8.Remove 2 bolts and removeLRT-51-003.
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12ENGINE
4
REPAIR Refit
9.Position new crankshaft pulley to vice.
10.Remove 3 bolts and remove damper from
crankshaft pulley.
11.Using a lint free cloth, thoroughly clean oil seal
recess and the running surface on crankshaft
pulley.
12.Fit crankshaft pulley.
13.FitLRT-51-003to crankshaft pulley and secure
with 2 bolts.
14.Fit new crankshaft pulley bolt and tighten to460
Nm (340 lbf.ft).
NOTE: It is recommended that a torque
multiplier is used to tighten crankshaft
pulley bolt.
15.Remove 2 bolts and removeLRT-51-003from
crankshaft pulley.
16.Fit damper to crankshaft pulley, fit bolts and
tighten to80 Nm (60 lbf.ft).
17.Fit auxiliary drive belt.
18.Fit radiator.See COOLING SYSTEM, Repair.
19.Fit underbelly panel.See CHASSIS AND
BODY, Repair.OIL SEAL - CRANKSHAFT - REAR
Service repair no - 12.21.20
Remove
1.Remove flywheel.See this Section.
2.Remove sump gasket.See this Section.
3.Remove 5 bolts securing oil seal housing to
cylinder block.
4.Remove seal housing.
Refit
5.Clean seal housing mating face on cylinder
block.
6.Position seal protector,LRT-12-061over
crankshaft boss. Fit new seal and housing
assembly and remove toolLRT-12-061.
CAUTION: Oil seal must be fitted dry.
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12ENGINE
6
REPAIR GASKET - CYLINDER HEAD
Service repair no - 12.29.02
Remove
NOTE: The following procedures cover
engines fitted with or without an EGR
cooler. The EGR cooler is bolted to the
front of the cylinder head.
1.Remove underbelly panel.See CHASSIS AND
BODY, Repair.
2.Drain cooling system.See COOLING
SYSTEM, Adjustment.
3.Remove camshaft cover gasket.See this
Section.
4.Remove cooling fan.See COOLING SYSTEM,
Repair.
5.Release clips and disconnect air flow meter from
air filter.
6.Disconnect multiplug from air flow meter.
7.Loosen clip and remove air inlet hose from
turbocharger.
8.Remove 3 bolts and remove exhaust manifold
heat shield.
9.Remove turbocharger oil feed banjo bolt and
discard sealing washers.
10.Remove 3 nuts, release turbocharger from
exhaust manifold, discard gasket and tie
turbocharger aside.
11.Remove 2 bolts securing engine harness to
camshaft carrier.
12.Disconnect fuel injector, coolant and compressor
sensors.
13.Disconnect 4 heater plug connectors.
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ENGINE
7
REPAIR
14.Disconnect MAP sensor multiplug from inlet
manifold.
15.Position engine harness clear of inlet manifold.
16.Disconnect vacuum hose from EGR valve.
17.Loosen clip screw and disconnect air intake
hose from EGR valve.
18.Release 3 clips and disconnect coolant hoses
from fuel cooler.
19.Disconnect fuel hoses, tank to fuel cooler and
connector block on cylinder head.
CAUTION: Plug the connections.
20.Disconnect fuel hose from fuel cooler and secure
to connector block on cylinder head. This is to
prevent contamination of the fuel injection
system.
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