fuel LAND ROVER DEFENDER 1999 Owner's Manual

MAINTENANCE
9
MAINTENANCE INTERCOOLER / COOLING SYSTEM
1.Visually check for any obstructions in the
radiator and intercooler matrix and remove
debris as necessary.
2.Visually check fan blades for damage.
3.Check cooling, intercooler and heating systems
for leaks, hoses and oil pipes for security and
condition.
4.Check accessible hose clips for tightness.
5.Check coolant level, top-up if necessary
Cooling System Top-Up
1.With engine cold, remove expansion tank filler
cap.
2.Top-up with recommended mixture of coolant
until level reaches mark on expansion tank.
3.Fit expansion tank filler cap.
Intercooler Flush
1.Remove intercooler.See FUEL SYSTEM,
Repair.
2.Flush intercooler element using Unicorn
Chemicals’C’Solve following the manufaturers
instructions.
3.Thoroughly dry intercooler ensuring that no trace
of solvent remains in the element.
4.Refit intercooler.See FUEL SYSTEM, Repair.AMBIENT AIR PRESSURE (AAP) SENSOR - Td5
1.Check ambient air pressure sensor for damage.
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MAINTENANCE
11
MAINTENANCE BRAKE FLUID
1.Renew brake fluid.See BRAKES,
Adjustment.AIR FILTER ELEMENT AND DUMP VALVE
1.Replace air cleaner element.See FUEL
SYSTEM, Repair.
2.Remove all dirt from dump valve.
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12ENGINE
12
DESCRIPTION AND OPERATION GENERAL
The Td5 diesel engine is a 2.5 litre, 5 cylinder, in-line direct injection unit having 2 valves per cylinder, operated by
a single overhead camshaft. The engine emissions on pre EU3 models comply with ECD2 (European Commission
Directive) legislative requirements. EU3 models comply with ECD3 legislative requirements. Both units employ
electronic engine management control, positive crankcase ventilation and exhaust gas recirculation to limit the
emission of pollutants. The unit is water cooled and turbo-charged and is controlled by an electronic engine
management system.
The cylinder block is a monobloc cast iron construction with an aluminium stiffening plate fitted to the bottom of the
cylinder block to improve lower structure rigidity. The cylinder head and sump are cast aluminium. An acoustic
cover is fitted over the upper engine to reduce engine generated noise.
The engine utilises the following features:
Electronic Unit Injectors (EUI’s)controlled by an Engine Management System for precise fuel delivery under
all prevailing operating conditions.
Turbochargingwhich delivers compressed air to the combustion chambers via an intercooler for improved
power output.
Fuel Cooler
Oil Cooler
Centrifuge Oil Filter
Hydraulic Lash Adjusterswith independent finger followers
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ENGINE
15
DESCRIPTION AND OPERATION Pistons
1.Bowl in piston head
2.Piston ring grooves3.Graphite coated aluminium alloy skirt
4.Gudgeon pin bore
The five pistons have graphite compound coated aluminium alloy skirts which are gravity die cast and machined.
Each of the pistons has phosphated, shaped gudgeon pin bores and a swirl chamber (bowl-in-piston) machined in
the head which partly contains the inlet air that is compressed during the combustion process and helps provide
turbulence for efficient air / fuel mixture to promote complete combustion. The recesses in the piston crowns also
provide clearance for the valve heads.
CAUTION: Pre EU3 and EU3 pistons are not interchangeable due to the EU3 piston combustion
bowl being offset.
The pistons are attached to the small-end of the connecting rods by fully floating gudgeon pins which are retained
in the piston gudgeon pin bushings by circlips.
The pistons and gudgeon pins are gallery cooled, oil being supplied under pressure from the piston lubrication jets
when the pistons are close to bottom dead centre.
Piston rings
Each piston is fitted with two compression rings and an oil control ring. The top compression ring is located in a
steel insert ring carrier which helps to provide a minimal reaction to compression forces.
The top ring is barrel-edged and chrome-plated, the 2nd compression ring is taper-faced and the oil control ring is
chrome-plated and features a bevelled ring with spring.
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ENGINE
25
DESCRIPTION AND OPERATION CYLINDER HEAD COMPONENTS
The cylinder head components are described below:
Cylinder head
The cylinder head is of aluminium construction. It is not possible to reface the cylinder head if it becomes worn or
damaged. An alloy camshaft carrier is bolted directly to the upper surface of the cylinder head. Two dowels are
included in the cylinder head upper face for correct location of the camshaft carrier.
The EU3 cylinder head has a single internal fuel rail for delivering fuel to the injectors and an external fuel pipe for
returning spill fuel back to the fuel connector block. Therefore, pre EU3 and EU3 cylinder heads are not
interchangeable.
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.
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.
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.
The camshaft is located between the cylinder head and the camshaft carrier, and the bearing journals are line
bored between the two components to form a matched pair.
CAUTION: Always fit plugs to open connections to prevent contamination.
The valve guides and valve seat inserts are sintered components which are an interference fit to the cylinder
head. The cylinder head machining also provide the locations for the electronic unit injectors, glow plugs, hydraulic
lash adjusters, finger followers and low pressure fuel rail.
Cooling to the cylinder head is provided by coolant flow through a water jacket machined into the cylinder head.
Drillings through the block provide lubrication channels for pressurised oil supply to cylinder head components
such as the lash adjusters, finger followers, rocker arms and camshaft bearings.
A coolant outlet elbow is fitted to the front LH side of the cylinder head to allow flow of coolant from the cylinder
head back to the radiator. A metal gasket is used to seal the joint between the water outlet elbow and the cylinder
head. A coolant temperature sensor is located in a port in the side of the water outlet elbow for monitoring coolant
temperature.
A stub pipe is connected at the front RH side of the cylinder block above the timing cover which connects a pipe to
supply oil to the vacuum pump. The timing chain tensioner adjuster is screwed in a thread in the cylinder head at a
location on the front RH side of the engine below the oil feed port for the vacuum pump.
An access hole for the camshaft gear is included at the front of the cylinder head which is sealed with a plastic
plug and rubber’O’ring. A press-fit core plug for the chain chest is located on the front face of the cylinder head.
A press-fit core plug for the cylinder head water jacket is located at the rear of the cylinder head and a threaded
brass plug for the water jacket is located on the LH side of the cylinder head beneath the exhaust manifold
assembly.
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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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ENGINE
27
DESCRIPTION AND OPERATION Camshaft
The camshaft is machined from cast steel and is located between the cylinder head and the camshaft carrier and
the six bearing journals are line bored between the two components to form a matched pair. The machined
camshaft has 15 lobes. Ten lobes operate the inlet and exhaust valves through hydraulic lash adjusters and finger
followers which are located below the camshaft. Five larger lobes activate the injector rockers which are located
above the camshaft on the rocker shaft and are used to generate fuel pressure in the EUI injectors.
The camshaft sprocket is driven via a Duplex chain connected to the crankshaft sprocket at a speed ratio of 2:1.
The camshaft sprocket is fixed to the front end of the camshaft by three bolts.
Camshaft lubrication is by splash and channel fed via pressurised oil flowing through galleries in the cylinder head.
Rocker shaft and rocker arms
Type A - Non EU3 Models - Engine Serial No. Prefixes 10P to 14P
Type B - EU3 Models - Engine Serial No. Prefixes 15P to 19p
1.Rocker arm adjusting screw
2.Rocker shaft
3.Rocker arm
4.EUI pin and roller assembly
5.Roller pin retention slug6.Camshaft lobe
7.Injector spring
8.Injector push-rod
9.Adjusting nut
The hollow rocker shaft is located in the camshaft carrier in six fixed mountings which sit above the camshaft. Six
bolts are used to lock the rocker shaft to the camshaft carrier. The front rocker shaft bearing has a ring dowel
located at the front rocker shaft mounting of the camshaft carrier for rocker shaft alignment. Two circlips hold each
rocker arm in position at the relevant positions on the rocker shaft.
CAUTION: The rocker shaft from a pre EU3 engine must not be fitted to an EU3 engine. This is
because the stroke of the EU3 injector has increased which requires the rocker to articulate over a
larger angle.
The camshaft end of each rocker arm features a roller which is free to rotate about a pin which passes through
two webs in the rocker arm, the roller pins are held in place by an interference fit retention slug passing through a
hole in the front web of each rocker arm.
To correctly function against the higher loads of the EU3 engine the geometry of the contact between the injector
pushrod and rocker arm adjusting screw has been modified. Both designs of adjusting screw are separately
available, with the EU3 version identified by an engraved dimple on the slotted end.
Rocker shaft and rocker arm lubrication is by splash and channel fed via pressurised oil flowing through galleries
in the cylinder head and through the rocker shaft.
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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
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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