1999 LAND ROVER DEFENDER engine oil

12ENGINE
34
DESCRIPTION AND OPERATION OIL COOLER / FILTER FLOW
(THERMOSTAT OPEN)
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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
36
DESCRIPTION AND OPERATION CYLINDER HEAD FLOW
1.Cast-in groove between cylinder head and
camshaft carrier
2.Rocker shaft flow
3.Lash adjuster supply channels (10 off)
4.Non-return valve
5.Chain lubrication jet supply6.Oil return from vacuum pump
7.Oil supply to timing chain tensioner adjuster
8.Oil supply to vacuum pump
9.Oil supply hole to camshaft sprocket and timing
chain
Oil passes to the cylinder head from the cylinder block via a non-return valve which is included to prevent oil
draining away from the lash adjusters when the engine is switched off.
Oil is passed to a cast-in groove between the top of the cylinder head and the camshaft carrier. The part of the
channel on the top left hand side of the cylinder head has ten cross-drillings which supply oil to the hydraulic lash
adjusters and finger followers. Lubrication oil fed to the lash adjusters passes up through the lash adjuster body
and into the socket of the finger followers. The oil exits the finger followers through a small hole to lubricate the
surfaces between the camshaft lobes and rollers.
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ENGINE
37
DESCRIPTION AND OPERATION An additional tapping is included at the front left hand side of the cylinder head to supply oil to the chain lubrication
jet and a through hole near the front centre of the cylinder head allows a passage of oil through from the cast-in
groove to lubricate the timing chain and camshaft sprocket.
At the centre front of the cylinder head, the cast-in groove channels oil into the rocker shaft via the front rocker
shaft fixing. Oil flow through the rocker shaft and clearance around the rocker shaft fixings provides oil feed to the
camshaft bearings.
A tapping towards the right hand side of the cylinder head diverts oil supply from the cast-in groove down to a stub
pipe which attaches to a feed line to the vacuum pump. An hydraulic tensioner is located below the vacuum stub
pipe which receives oil through a small hole in the side of the tensioner body to force a plunger against a plastic
faced adjuster shoe for timing chain tensioning. Oil from the vacuum pump is returned to the a port in the timing
chain cover via a short hose which connects to stub pipes at both ends using spring clips.
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ENGINE
1
ADJUSTMENT ENGINE OIL PRESSURE CHECK
Service repair no - 12.90.09.01
Check
1.Remove oil pressure switch.See Repair.
2.Connect pressure check kitLRT-12-052C
adaptor and gauge to oil pressure switch
position on oil cooler.
3.Check and if necessary, top-up engine oil.
4.Run engine at idle speed and check that oil
pressure is within limits given.
5.Switch off ignition.
6.Remove oil pressure check kitLRT-12-052C.
7.Clean oil spillage.
8.Fit oil pressure switch.See Repair.
Adjust
1.If engine oil pressure is not within specified
limits, check condition of oil pump and/or main
and connecting rod bearings.
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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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12ENGINE
2
REPAIR
13.Position camshaft in camshaft carrier.
14.Check end-float of camshaft using a DTI.
Camshaft end-float = 0.06 to 0.16 mm (0.002 to
0.006in).
15.Renew components as necessary to achieve
correct end-float.
CAUTION: Cylinder head and camshaft
carrier are machined together as an
assembly. If bearing surfaces in either
component are found to be damaged, complete
assembly must be replaced.
NOTE: The procedure for checking
camshaft bearing clearances is covered in
Td5 Engine Overhaul section - Cylinder
head - overhaul.Refit
16.Using a suitable cleaning solvent, clean mating
faces of cylinder head and camshaft carrier.
17.Blow out all oilways and waterways.
18.Ensure threaded holes in cylinder head and
camshaft carrier are clean and dry.
CAUTION: Support each end of the
cylinder head on blocks of wood. With
camshaft carrier bolted down some valves
and the injector nozzles will protrude from the
face of cylinder head.
19.Fit new adjusting screws fully into rocker arms.
Fit new lock nuts to screws but do tighten.
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 screw slot. These screws are not
interchangeable with those fitted to Engine Serial
No. Prefixes 10P to 14P.
20.Lubricate cams and bearing journals on
camshaft, cylinder head and camshaft carrier
with clean engine oil.
21.Position camshaft in cylinder head with the
timing pin hole in the vertical position.
22.Apply an even film of sealant, Part No. STC
4600 to camshaft carrier face as shown and
spread to an even film using a roller.
CAUTION: Ensure sealant does not block
oilways (arrowed) or contaminate
camshaft bearings. Assembly and bolt
tightening must be completed within 20 minutes
of applying sealant.
23.Fit camshaft carrier ensuring that it is correctly
located on dowels.
24.Fit and lightly tighten camshaft carrier bolts.
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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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