ecu LAND ROVER DEFENDER 1999 Repair Manual

12ENGINE
28
OVERHAUL Inspection
1.Clean all components.
2.Check condition of timing chain running surfaces
on adjustable and fixed guides.
CAUTION: Adjustable guide fitted to
Engine Serial No. Prefixes 15P to 19P may
be fitted to Engine Serial No. Prefixes 10P
to 14P provided that timing chain tensioner having
a YELLOW colour coded body is also fitted.
3.Check timing chains and sprockets for signs of
wear.
CAUTION: Timing chains and sprockets
fitted to Engine Serial No. Prefixes 15P to
19P may be fitted to Engine Serial No.
Prefixes 10P to 14P as an assembly only, oil pump
sprockets are interchangeable. Timing chains
fitted to Engine Serial No. Prefixes 15P to 19P
have BRONZE coloured timing links.
4.Check that drilling in timing chain lubrication jet
is clear.
5.Clean oil seal recess in timing cover and oil seal
running surface on crankshaft.
6.Remove all traces of sealant from mating faces
of timing cover and cylinder block using suitable
solvent.
CAUTION: Do not use metal scrapers.
7.Ensure bolt and dowel holes are clean and dry.
8.Clean oil pump sprocket bolt threads.Refit
1.Fit timing chain lubrication jet.
2.Fit bolt securing lubrication jet and tighten to10
Nm (7 lbf.ft).
3.If crankshaft has been rotated, check that No. 1
piston is at TDC using the following procedures:
4.Temporarily fit and lightly tighten a new
crankshaft pulley bolt.
5.Assemble a magnetic base DTI to cylinder block
top face, position stylus to cylinder block top face
and zero gauge.
6.Using crankshaft pulley bolt, rotate crankshaft
clockwise until No. 1 piston is at top of its stroke
and Woodruff key slot in crankshaft is at 12
o’clock position.
7.Position stylus of DTI to No. 1 piston crown and
rotate crankshaft until highest reading is
indicated on DTI.
8.Check that Woodruff key slot in crankshaft is still
at 12 o’clock position indicating No. 1 piston is at
TDC firing.
9.Remove DTI.
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12ENGINE
30
OVERHAUL
22.Fit oil seal guide, from seal kit, over end of
crankshaft.
23.Fit new oil seal into timing cover using
LRT-12-156.
CAUTION: Oil seal must be fitted dry.
24.RemoveLRT-12-156and oil seal guide.
25.Fit crankshaft pulley, fit crankshaft pulley bolt.
26.FitLRT-51-003to crankshaft pulley and secure
with 2 bolts.
27.Using assistance, restrain engine and using a
torque multiplier, tighten crankshaft bolt to460
Nm (340 lbf.ft).
WARNING: DUE TO THE HIGH TORQUE
LOADING REQUIRED, IT IS ESSENTIAL
THAT ENGINE IS ADEQUATELY
RESTRAINED.
28.RemoveLRT-51-003.
29.Position damper to crankshaft pulley, fit 3 bolts
and tighten to80 Nm (60 lbf.ft).
30.Fit sump gasket.See this Section.
31.Fit cylinder head gasket.See this Section.BEARINGS - CONNECTING RODS
Service repair no - 12.17.16.01
Remove
1.Remove oil pump.See this Section.
2.Mark cylinder reference number on each
connecting rod big-end bearing cap.
3.Make suitable alignment marks between each
big-end bearing cap and connecting rod.
CAUTION: Due to the’fracture split’
method of manufacturing connecting rods
and bearing caps, incorrect fitting of cap
to connecting rod will damage mating faces and
necessitate replacement of connecting rod
assembly.
4.Rotate crankshaft clockwise until No. 1 big-end
is at BDC.
5.Remove and discard 2 bolts securing No. 1
big-end bearing cap.
6.Remove bearing cap, remove and discard
big-end bearing shell.
7.Push connecting rod up cylinder bore until rod is
clear of crankshaft journal.
CAUTION: Ensure that connecting rod
does not contact cylinder bore or oil squirt
jet and piston does not contact the valves
or EUI’s if the cylinder head is fitted.
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12ENGINE
32
OVERHAUL
8.Carefully move connecting rod to one side of
journal and using feeler gauges, measure
end-float of connecting rod on journal:
Connecting rod end-float =0.2 to 0.5 mm
(0.008 to 0.021 in).
CAUTION: If end-float exceeds limits
given, replace connecting rod and repeat
end-float check - See pistons, connecting
rods and cylinder bores.
9.Repeat above procedures for remaining big-end
bearings.
10.Fit oil pump.See this Section.PISTONS, CONNECTING RODS AND CYLINDER
BORES
Service repair no - 12.17.02.01
Remove
1.Remove cylinder head gasket.See this
Section.
2.Remove connecting rod bearings.See this
Section.
3.Remove ridge of carbon from top of cylinder
bore.
4.Suitably identify each piston and connecting rod
assembly to its respective cylinder bore.
5.Carefully push connecting rod to top of cylinder
bore taking care that connecting rod does not
contact oil squirt jet or cylinder wall, remove
each piston and connecting rod assembly in
turn.
6.Using a suitable expander, remove and discard
piston rings from pistons.
7.Using a squared off end of an old piston ring,
clean carbon from ring grooves.
8.Clean carbon from piston crown and skirt.
CAUTION: Do not use abrasives on
graphited area of piston skirt, do not use a
wire brush or scraper on any part of the
pistons.
9.Secure connecting rod in a soft jawed vice.
10.Suitably identify each piston to its connecting rod
and fitted position of piston on rod.
11.Using suitable circlip pliers, remove and discard
2 circlips securing gudgeon pin.
12.Push gudgeon pin out of piston and connecting
rod; remove piston.
13.Suitably identify each gudgeon pin to its
respective piston.
14.Repeat above procedures for each piston.
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ENGINE
35
OVERHAUL Piston ring gaps - Checking
1.Insert new compression and oil control piston
rings in turn into No. 1 cylinder bore 30 mm (1.25
in) from top of bore and check ring fitted gaps;
ensure rings are kept square to bore when
checking gaps.
1st compression ring fitted gap =0.30 to 0.40
mm (0.012 to 0.016 in)
2nd compression ring fitted gap =0.40 to 0.60
mm (0.016 to 0.024 in)
Oil control ring fitted gap =0.25 to 0.50 mm
(0.01 to 0.02 in)
Repeat for each cylinder bore in turn.
CAUTION: Ensure rings are suitably
identified with the cylinder bore in which
they were checked and are fitted to the
piston for that bore.
2.Fit oil control expander and ring to piston.
3.Fit 2nd compression ring with’TOP’marking
upwards.
4.Fit 1st compression ring with’TOP’marking
upwards.
5.Check piston ring to groove clearance:
1st compression ring -Not measured
2nd compression ring =0.050 to 0.082 mm
(0.02 to 0.003 in)
Oil control ring =0.050 to 0.082 mm (0.02 to
0.003 in)
Pistons and connecting rods - Assembling
1.Lubricate gudgeon pin, gudgeon pin holes in
piston and small-end bush with engine oil.
2.Position piston to its respective connecting rod
with arrow on piston crown on the same side as
the cast boss on the connecting rod.
3.Fit gudgeon pin to its respective piston and
connecting rod; secure with new circlips.
CAUTION: Ensure circlips are fully seated
in their grooves.
4.Repeat above procedures for remaining pistons.
5.Lubricate piston rings and cylinder bores with
engine oil.
6.Check that rings are free to rotate, position ring
gaps at 120°to each other and away from the
thrust - LH side of piston - viewed from front of
piston.
7.Using a suitable piston ring clamp, compress
piston rings.
8.Insert connecting rod and piston into its
respective cylinder bore, ensuring that the arrow
on piston crown and the cast boss on connecting
rod are facing towards the front of the cylinder
block.
CAUTION: Ensure that connecting rod
does not contact cylinder bore or oil squirt
jet. Do not pull connecting rod fully down
cylinder bore at this stage.
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12ENGINE
36
OVERHAUL 9.Check that the cut-out in piston skirt is
positioned above the oil squirt jet.
10.Repeat for other pistons in turn ensuring that
pistons and connecting rods are fitted in cylinder
bores from which they were removed.
11.Fit connecting rod bearings.See this Section.
CAUTION: If new pistons, connecting rods
or crankshaft have been fitted, it will be
necessary to select correct thickness of
cylinder head gasket.See this Section.CRANKSHAFT
Service repair no - 12.21.33.01
Remove
1.Remove timing chain and sprockets.See this
Section.
2.Remove crankshaft rear oil seal.See this
Section.
3.Remove connecting rod bearings.See this
Section.
4.Check that cylinder reference number is on each
main bearing cap. Make suitable alignment
marks between each main bearing cap and
cylinder block.
5.Starting at No. 3 main bearing cap and working
outwards, progressively loosen, then remove 2
bolts securing each cap. Discard main bearing
cap bolts.
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ENGINE
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OVERHAUL
6.Fit 2 slave bolts into each main bearing cap in
turn and ease bearing caps from cylinder block.
7.Remove and discard bearing shells from each
cap.
NOTE: These bearing shells are plain.
8.Using assistance, remove crankshaft.
9.Remove and discard main bearing shells and 2
thrust washers from cylinder block.
NOTE: These bearing shells are grooved.
10.Remove Torx screw securing each oil squirt jet
to cylinder block, remove squirt jets.Cylinder block - Inspection
1.Clean main bearing shell and thrust washer
locations in cylinder block, ensure bolt holes are
clean and dry.
2.Clean main bearing caps.
3.Clean crankshaft bearing journals, check oilways
are clear.
4.Ensure drillings in oil squirt jets are clear.
5.Check core plugs in cylinder block for corrosion
or signs of leakage, seal replacement plugs with
Loctite 243.
Crankshaft - Inspection
1.Check crankshaft main and big-end bearing
journals for scoring, wear and ovality, make 3
checks at 120°intervals in centre of journals.
Crankshaft bearing journal diameters:
Main bearings =
62.000 mm±0.013 mm (2.441 in±0.001 in)
Big-end bearings =
54.000±0.01 mm (2.125±0.0004in)
CAUTION: Crankshafts may not be
reground, only one size of main and
big-end bearing shell is available and if
journals are found to be scored, oval or worn,
crankshaft must be replaced. Main and big-end
bearing shells and thrust washers must be
replaced whenever they are removed.
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12ENGINE
38
OVERHAUL Crankshaft spigot bush
1.Check crankshaft spigot bush for wear, replace if
necessary using the following procedures:
2.Secure crankshaft in a suitably padded vice.
3.Tap a thread in spigot bush to accommodate a
suitable impulse extractor.
4.Fit impulse extractor to spigot bush.
5.Remove spigot bush.
6.Clean spigot bush recess in crankshaft.
7.Fit new spigot bush to crankshaft using a
suitable mandrel.
Crankshaft - Refit
1.Fit oil squirt jets, fit Torx screws and tighten to8
Nm (6 lbf.ft).
2.Lubricate new, grooved, main bearing shells with
engine oil and fit to cylinder block.
3.Lubricate new thrust washers with engine oil and
fit, grooved side facing outwards, to recess in
each side of cylinder block No. 3 main bearing.
4.Lubricate crankshaft journals with engine oil and
using assistance, position crankshaft in cylinder
block.
5.Lubricate new, plain, main bearing shells with
engine oil and fit to main bearing caps.
6.Fit main bearing caps in their original fitted
positions ensuring that reference marks are
aligned.
7.Fit and lightly tighten new main bearing cap
bolts.
CAUTION: Do not lubricate bolt threads.
8.Starting with No. 3 main bearing cap and
working outwards, tighten main bearing cap bolts
to:
Stage 1 -33 Nm (24 lbf.ft)
Stage 2 -Further 90
°
CAUTION: Do not carry out stages 1 and 2
in one operation.
9.Check that crankshaft rotates smoothly.
10.Assemble a magnetic base DTI to front of
cylinder block with stylus of gauge on end of
crankshaft.
11.Using suitably padded levers, move crankshaft
rearwards and zero DTI.
12.Move crankshaft forwards and note crankshaft
end-float reading on gauge.
Crankshaft end-float =0.02 to 0.25 mm (0.001
to 0.011 in)
CAUTION: Oversize thrust washers are not
available, if end-float exceeds figure given,
crankshaft must be replaced.
13.Remove DTI.
14.Fit connecting rod bearings.See this Section.
15.Fit timing chain and sprockets.See this
Section.
16.Fit crankshaft rear oil seal.See this Section.
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EMISSION CONTROL
9
DESCRIPTION AND OPERATION EGR MODULATOR
1.Port to vacuum source (white band)
2.Port to EGR valve (blue band)3.Port to atmosphere via in-line filter (green band)
4.Harness connector
The EGR modulator is located on a plate fixed to the inner RH front wing. The modulator is attached to the plate
by two studs, each with two nuts which secure the assembly to a rubber mounting, which helps reduce noise. The
modulator must be mounted vertically with the two vacuum ports uppermost.
Modulator operation is controlled by a signal from the ECM which determines the required amount of EGR needed
in response to inputs relating to air flow, engine operation, and ambient conditions. The modulator has a two pin
connector at its base to connect it to the ECM via the engine harness.
The modulator features three ports:
The top port is identified by a white band and connects to a T-piece in the vacuum line via a small bore light
brown plastic hose. The two other ports on the T-piece connect to the vacuum line hoses of black vinyl tubing
between the vacuum pump and the brake servo assembly attached to the bulkhead. The vacuum pump end of
the tubing terminates in a rubber elbow, which gives a vacuum tight seal on the suction port of the vacuum
pump. The brake servo end of the tubing terminates with a non-return valve in a plastic housing which plugs
into the front face of the brake servo housing.
The middle port is identified by a blue band, and connects to the suction port on the EGR valve through a small
bore blue plastic hose.
The lower port is identified by a green band and connects to atmosphere through an in-line filter via a small
bore green plastic hose.
The blue and brown vacuum hoses are protected by corrugated plastic sheaths. The ends of the hoses are fitted
with rubber boots to ensure vacuum tight seals at the component ports.
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17EMISSION CONTROL
10
DESCRIPTION AND OPERATION INLET THROTTLE (ILT) MODULATOR
1.Port to vacuum source (white band)
2.Port to ILT valve (blue band)
3.Port to atmosphere via in-line filter (green band)
4.Harness connector (green)
The ILT modulator is located on a plate fixed to the inner wing on the RH side of the engine below the EGR
modulator. The modulator is attached to the plate by two through-studs, each with two nuts which secure the
modulator assembly to a rubber mounting which helps to reduce noise. The modulator must be mounted in the
vertical orientation with the two vacuum ports uppermost.
The modulator operation is controlled by a signal from the ECM which determines the required ratio of exhaust
gas to fresh inlet air needed in response to inputs relating to air flow and engine operating and ambient conditions.
The modulator has a green two-pin connector at its base to connect it to the ECM through the engine harness.
The ILT valve modulator features three ports:
The top port is identified by a white band and connects to a’T’-piece in the vacuum line via a small-bore brown
plastic hose where it is connected in parallel with the vacuum source line to the EGR valve modulator. The two
other ports on the’T’-piece connect vacuum line hoses of black vinyl tubing between the vacuum pump
attached to the alternator and the brake-servo assembly attached to the bulkhead.
The middle port is identified by a blue band and connects to the suction port on the ILT valve through a
small-bore blue plastic hose.
The lower port is identified by a green band and connects to atmosphere through an in-line filter via a green
plastic hose and a three-way connector positioned in-line between the modulators and the filter. The ILT
modulator hose is connected opposite to the two parallel ports at the three-way connector which connect the
vent lines to the EGR valve modulator and the in-line filter. The other port of the in-line filter vents directly to
atmosphere.
The blue and brown vacuum hoses are protected by corrugated plastic sheaths. The ends of the hoses are fitted
with rubber boots to ensure vacuum tight seals at the component ports.
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17EMISSION CONTROL
14
DESCRIPTION AND OPERATION EGR SYSTEMS
There are two types of exhaust gas recirculation system used with the Td5 engine dependent on legislation and
market requirements, these are type 1 and type 2.
Type 1 EGR system is fitted to all Td5’s built up to the introduction of 2002 MY, except for Japanese specification
vehicles.
Type 2 EGR system is fitted to all Japanese specification vehicles and was introduced into European markets for
2002 MY to meet EU3 emission requirements. An additional feature introduced at 2002 MY is the EGR cooler,
which is bolted to the front of the cylinder head.
EGR System - Type 1
This EGR system features a modulator which is electrically controlled to modulate a vacuum source to the EGR
valve. The controlled vacuum opens the valve by the amount required to ensure the optimal proportion of exhaust
gas is allowed through to the inlet manifold to be combined with the fresh air intake. Control feedback is achieved
by monitoring the mass of fresh air flowing through the MAF sensor.
EGR modulator operation is controlled by a signal from the ECM, which determines the required amount of EGR
needed in response to inputs relating to air flow and engine operating and ambient conditions. The ECM is
low-side driven, sinking current returned from the vacuum modulator for switching operating condition.
The exhaust gases are routed from the exhaust manifold through a shaped metal pipe which connects to the
underside of the EGR valve. The pipe is held securely in position to the front of the cylinder head using a clamp
bracket. The EGR pipe is attached to a mating port at the front end of the exhaust manifold using 2 Allen screws,
and at the EGR valve assembly by a metal band clamp. The 2 Allen screws should be replaced every time the
EGR pipe is removed.
CAUTION: Extreme caution should be exercised when removing and refitting the EGR pipe to
avoid damage.
When a vacuum is applied to the EGR suction port, it causes a spindle with sealing disc (EGR valve) to be raised,
thus opening the port at the EGR pipe to allow the recirculated exhaust gas to pass through into the inlet manifold.
The valve is spring loaded so that when the vacuum is removed from the suction port the valve returns to its rest
position to tightly close the exhaust gas port.
By controlling the quantity of recirculated exhaust gas available in the inlet manifold, the optimum mix for the
prevailing engine operating conditions can be maintained. This ensures the intake gas to the combustion
chambers will have burning rate properties which will reduce NO
Xemissions to an acceptable level. Normally, full
recirculation is only applicable when NO
Xemissions are most prevalent.
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