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ENGINE
35
DESCRIPTION AND OPERATION 1.To cylinder block main gallery (from rear of oil cooler housing)
2.Oil cooler housing
3.Oil pressure switch
4.Full-flow filter
5.Centrifuge filter
6.Return to sump
7.Flow from oil pump (via cylinder block)
8.Oil cooler matrix
When the engine temperature is below 74°C, the thermostat in the full-flow filter adaptor housing is closed and a
proportion of the oil flow to the main oil gallery is diverted to the oil cooler to supply an oil feed to the turbocharger
bearings. Oil passes through the oil cooler to the front gallery in the oil cooler housing where there is a tapping to
connect the feed pipe to the turbocharger. Oil used by the turbocharger bearings is returned to the sump through
an oil drain pipe which connects to a port in the LH side of the cylinder block.
The remainder of the oil flow leaving the full-flow filter outlet is passed into the cylinder block via a port at the rear
of oil cooler rear gallery.
When the oil temperature rises above 74°C the thermostat in the full-flow filter housing begins to open to allow a
proportion of the oil from the full-flow filter to pass through the oil cooler before it reaches the main oil gallery in the
cylinder block. In this instance, oil supply to the turbocharger bearings is fed directly from the full-flow filter without
first passing through the oil cooler. Between 74°C and 88°C the thermostat valve plunger opens by about 9 mm
(0.3 in) to allow proportionally more oil to flow through the oil cooler before being passed to the cylinder block main
oil delivery gallery. Above 88°C the thermostat valve continues to open by about 1mm (0.03 in) for every 10°C
increase in temperature until the valve is fully open, when all the oil flow to the cylinder block is forced to pass to
the cylinder block via the oil cooler.
An oil pressure switch is located in a port in the rear gallery of the oil cooler housing to sense the oil pressure level
before flow enters the main oil gallery in the engine block. A warning lamp in the instrument cluster is switched on
if the oil pressure is detected as being too low.
Drillings from the cylinder block main oil gallery direct oil to the crankshaft main bearings and cross drillings in the
crankshaft direct oil to the big-end bearings. An additional five drillings in the cylinder block supply oil at reduced
pressure to the oil squirt jets for piston cooling and gudgeon pin lubrication.
Oil supply from the cylinder block is then passed to the cylinder head galleries through a non-return valve which is
included as an integral item in the lower face of the cylinder head.
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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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12ENGINE
14
REPAIR
9. Not EU3 model:-Apply two 3 mm diameter
beads of sealant, Part No.STC 5433 to areas’A’
shown on illustration.
CAUTION: Excessive use of sealant could
result in blockage of oil drain hole,
arrowed’B’in illustration.
10.Fit new gasket to camshaft cover. fit cover and
tighten bolts to10 Nm (7 lbf.ft).
11.Position breather hose and secure clip.
12.Fit engine acoustic cover.
13.Reconnect battery negative lead.
14.Fit battery cover.ENGINE AND ANCILLARIES
Service repair no - 12.41.01.99
Remove
1.Remove underbelly panel.See CHASSIS AND
BODY, Repair.
2.Drain engine oil.
3.Remove radiator.See COOLING SYSTEM,
Repair.
4.Remove turbocharger.See FUEL SYSTEM,
Repair.
5.Remove starter motor.See ELECTRICAL,
Repair.
6.Remove air filter.See FUEL SYSTEM, Repair.
7.Loosen clip screw and release air intake hose
from intake elbow.
8.Release clips and disconnect coolant hoses
from fuel cooler and coolant rail.
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ENGINE
19
REPAIR 70.Connect coolant hoses to fuel cooler and coolant
rail and secure clips.
71.Fit air intake hose to intake elbow and tighten
clip screw.
72.Fit starter motor.See ELECTRICAL, Repair.
73.Fit turbocharger.See FUEL SYSTEM, Repair.
74.Fit radiator.See COOLING SYSTEM, Repair.
75.Fit air filter.See FUEL SYSTEM, Repair.
76.Fill engine with oil.
77.Fit underbelly panel.See CHASSIS AND
BODY, Repair.MOUNTING - FRONT - LH
Service repair no - 12.45.01
Remove
1.Remove centrifuge assembly.See this
Section.
2.Remove 3 bolts, remove oil filter adaptor
housing and discard gasket.
3.Fit suitable lifting chains to support engine.
4.Remove 2 nuts securing engine mounting to
chassis.
5.Remove 4 bolts securing engine mounting
bracket to cylinder block.
6.Remove nut securing mounting to mounting
bracket.
7.Remove mounting and mounting bracket.
8.Remove mounting shield.
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12ENGINE
20
REPAIR Refit
9.Fit shield to mounting ensuring cut-away portion
is correctly aligned.
10.Fit mounting and mounting bracket.
11.Fit mounting bracket to cylinder block bolts and
tighten to48 Nm (35 lbf.ft).
12.Fit nuts securing mounting to chassis and tighten
to85 Nm (63 lbf.ft).
13.Fit mounting to mounting bracket nut and tighten
to85 Nm (63 lbf.ft).
14.Remove engine support chains.
15.Clean oil filter adaptor housing and mating face.
16.Fit oil filter adaptor housing using a new gasket
and tighten bolts to25 Nm (18 lbf.ft).
17.Fit centrifuge assembly.See this Section.MOUNTING - FRONT - RH
Service repair no - 12.45.03
Remove
1.Remove engine acoustic cover.See this
Section.
2.Remove fixings, remove battery cover.
3.Disconnect battery negative lead.
4.Raise front of vehicle.
WARNING: Support on safety stands.
5.Remove 4 bolts, move fuel cooler to one side.
6.Fit suitable lifting chains to support engine.
7.Remove 2 nuts securing engine mounting to
chassis.
8.Remove 4 bolts securing engine mounting
bracket to cylinder block.
9.Remove nut securing mounting to mounting
bracket.
10.Remove mounting and mounting bracket.
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ENGINE
23
REPAIR FILTER - OIL
Service repair no - 12.60.04
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
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 manifold heat
shield.
7.Clean area around filter head and place a
container beneath engine.
8.Using a strap wrench, unscrew and discard filter.
Refit
9.Clean mating face of filter head.
10.Lubricate sealing ring of new filter with clean
engine oil.
11.Fit filter and tighten by hand until it seats then
tighten a further half turn.
12.Start and run engine to check for leaks.
13.Stop engine, wait a few minutes, then check oil
level.
14.Top up engine oil.
15.Position exhaust manifold heat shield and
tighten 3 bolts.
16.Position air inlet hose to turbocharger and
tighten clip screw.
17.Connect air flow meter to air filter and secure
clips.
18.Connect air flow meter multiplug.
19.Connect breather hose and secure with clip.
20.Position engine acoustic cover.
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12ENGINE
28
REPAIR SWITCH - OIL PRESSURE
Service repair no - 12.60.50
Remove
1.Remove fixings and remove engine acoustic
cover.
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.Release clip screw and remove air inlet hose
from turbocharger.
6.Remove 3 bolts and remove exhaust manifold
heat shield.
7.Disconnect multiplug from oil pressure switch.
8.Position container below switch to catch oil
spillage.
9.Remove oil pressure switch.
Refit
10.Clean oil pressure switch threads.
11.Fit oil pressure switch and tighten to9Nm(7
lbf.ft).
12.Connect switch multiplug.
13.Position exhaust manifold heat shield and
tighten M6 bolts to10 Nm (7 lbf.ft)and M8 bolt
to25 Nm (18 lbf.ft).
14.Position air inlet hose to turbocharger and
tighten clip screw.
15.Connect air flow meter to air filter and secure
clips.
16.Connect air flow meter multiplug.
17.Connect breather hose and secure clip.
18.Fit and secure engine acoustic cover.
19.Top up engine oil.
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ENGINE
29
REPAIR VALVE - RELIEF - OIL PRESSURE
Service repair no - 12.60.56
Remove
1.Remove sump gasket.See this Section.
2.Remove and discard oil pressure relief valve
plug from oil pump housing.
3.Remove spring and valve.
Refit
4.Clean valve and spring.
5.Clean valve seating inside oil pump housing.
6.Lubricate valve and seating.
7.Fit valve and spring to pump.
8.Apply Loctite 243 sealant to threads of a new
plug.
9.Fit plug and tighten to23 Nm ( 17 lbf.ft).
10.Fit sump gasket.See this Section.
11.Check engine oil level, top-up if necessary.COOLER - ENGINE OIL
Service repair no - 12.60.68
Remove
1.Drain cooling system.See COOLING
SYSTEM, Adjustment.
2.Remove centrifuge assembly.See this
Section.
3.Remove clutch housing bolt and release coolant
pipe from rear of engine.
4.Release clip and coolant hose from oil cooler.
5.Disconnect oil pressure switch multiplug.
6.Remove oil filter element using a suitable strap
wrench.
7.Remove 3 bolts, remove oil filter adaptor and
discard gasket.
8.Remove 7 bolts, remove oil cooler and discard
gasket.
9.Remove oil pressure switch.
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