1999 LAND ROVER DEFENDER engine

COOLING SYSTEM
1
ADJUSTMENT DRAIN AND REFILL
Service repair no - 26.10.01
WARNING: Hot coolant
Drain
1.Remove engine acoustic cover.
2.Visually check engine and cooling system for
signs of coolant leaks.
3.Examine hoses for signs of cracking, distortion
and security of connections.
4.Position drain tray to collect coolant.
5.Remove expansion tank filler cap.
6.Loosen clip screws securing air inlet hose to
intercooler and inlet manifold, release and
remove hose.
7.Release clip and disconnect bottom hose from
radiator.
8.Allow cooling system to drain.
9.Disconnect bottom hose from radiator.Refill
1.Flush system with water under low pressure.
2.Do not use water under high pressure as it could
damage the radiator.
3.Connect bottom hose to radiator and secure
hose with clip.
4.Prepare coolant to required concentration.
5.Position heater temperature control to maximum
hot position.
6.Remove bleed screw from top hose.
7.Fill system slowly through coolant expansion
tank until a steady flow of coolant is emitted from
the bleed hole in top hose.
8.Fit bleed screw to top hose.
9.Continue filling system until coolant level
reaches’MAX’mark on expansion tank.
10.Fit expansion tank filler cap.
11.Position air intake hose and tighten clip screws.
12.Start and run engine until normal running
temperature is reached.
13.If fitted, DO NOT operate air conditioning.
14.Switch off engine and allow to cool.
15.Check for leaks and top-up coolant to’MAX’
mark on expansion tank.
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COOLING SYSTEM
1
REPAIR COUPLING - COOLING FAN
Service repair no - 26.25.19
Remove
1.Remove battery cover.
2.Disconnect battery negative lead.
3.Remove 3 bolts and remove engine acoustic
cover.
4.Remove cooling fan cowl.
NOTE: Thread is RH.
5.Remove cooling fan usingLRT-12-093and
LRT-12-094.
Refit
6.Position cooling fan and tighten using
LRT-12-093andLRT-12-094.
7.Fit cooling fan cowl.
8.Fit engine acoustic cover.
9.Reconnect battery negative lead.
10.Fit battery cover.THERMOSTAT
Service repair no - 26.45.09
Remove
1.Drain cooling system.See Adjustment.
2.Remove cooling fan.See this Section.
3.Release 3 clips and disconnect coolant hoses
from thermostat.
4.Remove thermostat.
Refit
5.Position thermostat, connect hoses and secure
with clips.
6.Fit cooling fan.See this Section.
7.Fill cooling system.See Adjustment.
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26COOLING SYSTEM
2
REPAIR PUMP - COOLANT
Service repair no - 26.50.01
Remove
1.Drain cooling system.See Adjustment.
2.Remove centrifuge.See ENGINE , Repair.
3.Release clip and hose from coolant pump cover.
4.Remove 5 bolts securing coolant pump cover.
5.Remove cover and coolant pump from housing
and discard’O’rings.Refit
6.Clean coolant pump housing and mating faces.
7.Fit new’O’rings to coolant pump and cover.
8.Fit coolant pump and cover and tighten bolts to9
Nm (7 lbf.ft).
9.Connect hose to pump cover and secure clip.
10.Refit centrifuge.See ENGINE , Repair.
11.Refill cooling system.See Adjustment.
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30MANIFOLD AND EXHAUST SYSTEM
2
DESCRIPTION AND OPERATION DESCRIPTION
General
The diesel engine has the inlet manifold attached to the right hand side of the engine and the exhaust manifold
attached to the left hand side of the engine. The inlet manifold directs cooled compressed air from the
turbocharger and intercooler into the cylinders, where it is mixed with fuel from the injectors. Exhaust gases from
the exhaust manifold can also be directed into the inlet manifold via a pipe from the exhaust manifold and an
Exhaust Gas Recirculation (EGR) valve on the inlet manifold. The exhaust manifold allows combustion gases from
the cylinders to leave the engine where they are directed into the exhaust system and turbocharger.
The exhaust system is attached to the turbocharger and is directed along the underside of the vehicle to emit
exhaust gases from a tail pipe at the rear of the vehicle. A silencer is installed midway along the system and a
second tail silencer is located at the rear of the vehicle.
Inlet manifold
The inlet manifold is a one piece aluminium casting. The manifold is secured to the cylinder head with two studs
and flanged nuts and eight flanged bolts. A one piece laminated gasket seals the manifold to the cylinder head.
Four threaded bosses on the manifold provide for the attachment of the fuel cooler. The fuel cooler is secured to
the manifold with four bolts. A boss with two threaded holes allows for the attachment of the combined intake air
temperature/pressure sensor. The sensor is secured to the manifold with two screws and sealed with a gasket.
At the forward end of the manifold, a machined face and four threaded holes provide for the attachment of the
EGR valve. The valve is sealed to the manifold with a gasket.
Exhaust manifold
The exhaust manifold is made from cast iron. The manifold has five ports, one from each cylinder, which merge
into one flanged outlet connection positioned centrally on the manifold.
The manifold is attached to the cylinder head with ten studs and flanged nuts. A laminated metal gasket seals the
manifold to the cylinder head. The flanged outlet on the manifold provides the attachment for the turbocharger,
which is attached with three studs and flanged nuts and sealed with a metal laminated gasket.
A second flanged outlet, located at the forward end of the manifold, provides attachment for the EGR pipe. The
EGR pipe is secured to the manifold with two cap screws and connected to the EGR valve mounted on the inlet
manifold. There is no gasket used between the pipe and the exhaust manifold.
Exhaust system
The exhaust system comprises a front pipe, an intermediate pipe which incorporates a silencer and a tail pipe
assembly which also has a silencer. The exhaust system is constructed mainly of 63 mm (2.48 in) diameter
extruded pipe with a 1.5 mm (0.06 in) wall thickness. All pipes are aluminized to resist corrosion and the silencers
are fabricated from stainless steel sheet.
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MANIFOLD AND EXHAUST SYSTEM
3
DESCRIPTION AND OPERATION Front pipe assembly
The front pipe is of welded and fabricated tubular construction. The front pipe is connected to a flange on the
turbocharger and secured with three flanged nuts and sealed with a metal laminated gasket. The front pipe
incorporates a flexible pipe near the connection with the turbocharger and terminates in a flanged connection with
the intermediate pipe.
The flexible pipe is formed into a concertina shape with woven metal strands around its outer diameter. The
flexible pipe allows for ease of exhaust system alignment and also absorbs engine vibration. The woven metal
strands also increase the longevity of the flexible pipe.
The front pipe is attached via a bracket and a mounting rubber to the chassis. The mounting rubber allows ease of
alignment and vibration absorption.
Intermediate pipe and silencer
The intermediate pipe is of welded and fabricated tubular construction. It connects at its forward end to the front
pipe flange. Two captive studs on the intermediate pipe flange allow for attachment to the front pipe with locknuts.
The rear section of intermediate pipe connects to the tail pipe assembly via a flanged joint, sealed with a metal
gasket and secured with locknuts and studs.
The forward and rear sections are joined by a silencer. The silencer is fabricated from stainless steel sheet to form
the body of the silencer. An end plate closes each end of the silencer and is attached to the body with seam joints.
Perforated baffle tubes, inside the silencer, are connected to the inlet and outlet pipes on each end plate. Internal
baffle plates support the baffle tubes and, together with a stainless steel fibre packing, absorb combustion noise
as the exhaust gases pass through the silencer.
The intermediate pipe is attached by two brackets, positioned at each end of the silencer, and two mounting
rubbers to the chassis. The mounting rubber allows for ease of alignment and vibration absorption.
Tail pipe assembly
The tail pipe is of welded and fabricated construction. The tail pipe connects to the intermediate pipe with a
flanged joint secured with locknuts and sealed with a metal gasket. The pipe is shaped to locate above the rear
axle allowing clearance for axle articulation. The pipe is also curved to clear the left hand side of the fuel tank
which has a reflective shield to protect the tank from heat generated from the pipe.
A fabricated silencer is located at the rear of the tail pipe. The silencer is circular in section and is constructed from
stainless steel sheet. A baffle tube is located inside the silencer and the space around the baffle tube is packed
with a stainless steel fibre. The holes in the baffle tube allow the packing to further reduce combustion noise from
the engine. The tail pipe from the silencer is curved downwards at the rear of the vehicle and directs exhaust
gases towards the ground. The curved pipe allows the exhaust gases to be dissipated by the airflow under the
vehicle and prevents the gases from being drawn behind the vehicle.
The tail pipe is attached by a bracket, positioned forward of the silencer, and a mounting rubber to the chassis.
The mounting rubber allows ease of alignment and vibration absorption.
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MANIFOLD AND EXHAUST SYSTEM
1
REPAIR PIPE - EXHAUST - FRONT
Service repair no - 30.10.09
Remove
1.Remove engine acoustic cover.See ENGINE ,
Repair.
2.Release clip and disconnect breather hose from
camshaft cover.
3.Release clips and disconnect air flow meter from
air filter.
4.Disconnect multiplug from air flow meter.
5.Loosen clip screw and remove air inlet hose
from turbocharger.
6.Remove 3 bolts and remove exhaust manifold
heat shield.
7.Remove 3 nuts, release front pipe from
turbocharger and discard gasket.
8.Remove underbelly panel.See CHASSIS AND
BODY, Repair.
9.Remove 8 nuts and bolts and remove chassis
cross member.
10.Remove 2 nuts, release front pipe from
intermediate silencer.
11.Release front pipe from mounting rubber and
remove pipe.
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30MANIFOLD AND EXHAUST SYSTEM
2
REPAIR Refit
12.Clean front pipe and mating faces.
13.Position front pipe and using new gaskets, align
to intermediate pipe and turbocharger.
14.Connect mounting rubber to front pipe.
15.Fit and tighten exhaust flange nuts to27 Nm (20
lbf.ft).
16.Fit chassis cross member, and tighten bolts to
45 Nm (33 lbf.ft)
17.Fit underbelly panel.See CHASSIS AND
BODY, Repair.
18.Position new gasket and front pipe to
turbocharger and tighten nuts to27 Nm (20
lbf.ft).
19.Position exhaust manifold heat shield and
tighten M6 bolts to10 Nm (7 lbf.ft)and M8 bolt
to25 Nm(18 lbf.ft).
20.Position air inlet hose to turbocharger and
tighten clip screw.
21.Connect air flow meter to air filter and secure
clips.
22.Connect air flow meter multiplug.
23.Connect breather hose and secure clip.
24.Fit engine acoustic cover.See ENGINE ,
Repair.SILENCER - INTERMEDIATE
Service repair no - 30.10.11
Remove
1.Raise vehicle on a 4 post ramp.
2.Remove 2 nuts securing intermediate silencer to
front pipe.
3.Remove 3 nuts securing intermediate silencer to
tail pipe.
4.Release intermediate silencer from rubber
mountings and remove silencer.
5.Remove and discard gasket from tail pipe flange.
Refit
6.Clean intermediate silencer and mating faces.
7.Fit new gasket to tail pipe flange.
8.Position intermediate silencer to rubber
mountings and tail pipe flange.
9.Fit nuts securing intermediate silencer to front
pipe and tail pipe and tighten to25 Nm (18
lbf.ft).
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MANIFOLD AND EXHAUST SYSTEM
3
REPAIR EXHAUST - TAIL PIPE AND SILENCER
Service repair no - 30.10.22
Remove
1.Raise vehicle on ramp.
2.Remove 3 nuts securing silencer to tail pipe.
3.Release tail pipe from mounting and remove tail
pipe.
4.Collect silencer to tail pipe gasket.
Refit
5.Clean silencer and tail pipe mating faces.
6.Position tail pipe and secure on mounting
rubber.
7.Using a new gasket, align silencer to tail pipe.
8.Fit nuts to silencer and tighten to25 Nm (18
lbf.ft).GASKET - INLET MANIFOLD
Service repair no - 30.15.08
Remove
1.Remove battery cover.
2.Disconnect battery negative lead.
3.Remove 3 bolts and remove engine acoustic
cover.
4.Release retainers and remove cooling fan cowl.
5.Disconnect multiplug from manifold air pressure
sensor and release 4 glow plug leads.
6.Remove 4 bolts, release EGR valve from inlet
manifold and discard gasket.
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