fuel pressure FORD SIERRA 1986 1.G SOHC Engines Workshop Manual
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Page 6 of 24
2.0 litre engine
General
Engine type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Four-cylinder, in-line, single overhead camshaft
Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3-4-2
Engine codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NES and NET (carburettor, except P100), NRB and N4A (fuel
injection), and NAE (P100)
Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.82 mm
Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76.95 mm
Cubic capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1993 cc
Compression ratio:
All except engine code NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9.2:1
Engine code NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8.2:1
Compression pressure at starter motor speed:
All except engine code NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 to 13 bar
Engine code NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 to 12 bar
Maximum continuous engine speed:
Engine code NES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5850 rpm
Engine codes NET and NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5800 rpm
Engine codes NRB and N4A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6050 rpm
Maximum engine power (DIN):
Engine codes NES and NET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77kW at 5200 rpm
Engine codes NRB and N4A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85kW at 5500 rpm
Engine code NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57kW at 4500 rpm
Maximum engine torque (DIN):
Engine codes NES and NET. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157 Nm at 4000 rpm
Engine codes NRB and N4A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160 Nm at 4000 rpm
Engine code NAE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143 Nm at 2800 rpm
Cylinder bore diameter
Standard class 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.800 to 90.810 mm
Standard class 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.810 to 90.820 mm
Standard class 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.820 to 90.830 mm
Standard class 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.830 to 90.840 mm
Oversize class A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.310 to 91.320 mm
Oversize class B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.320 to 91.330 mm
Oversize class C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.330 to 91.340 mm
Standard service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.830 to 90.840 mm
Oversize 0.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.330 to 91.340 mm
Oversize 1.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.830 to 91.840 mm
Crankshaft
Specifications as for 1.3 litre engine except for the following:
Main bearing thrustwasher thickness:
All except engine codes NES, NET, NRB and N4A from 1987:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.30 to 2.35 mm
Oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.50 to 2.55 mm
Engine codes NES, NET, NRB and N4A from 1987:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.28 to 2.33 mm
Oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.48 to 2.53 mm
Pistons and piston rings
Piston diameter:
Standard class 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.765 to 90.775 mm
Standard class 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.775 to 90.785 mm
Standard class 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.785 to 90.795 mm
Standard class 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.795 to 90.805 mm
Standard service:
Up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.780 to 90.805 mm
From 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90.790 to 90.815 mm
Service oversize 0.5:
Up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.280 to 91.305 mm
From 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.290 to 91.315 mm
Service oversize 1.0:
Up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.780 to 91.805 mm
From 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91.790 to 91.815 mm
2A¥6SOHC engines
Page 7 of 24
Piston ring end gap:
Top:
Up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.038 to 0.048 mm
From 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.400 to 0.600 mm
Centre:
Up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.038 to 0.048 mm
From 1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.400 to 0.600 mm
Bottom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.400 to 1.400 mm
Auxiliary shaft
Endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.050 to 0.204 mm (0.002 to 0.008 in)
Cylinder head
Specifications as for 1.3 litre engine
Valves
Specifications as for 1.3 litre engine except for the following:
Valve clearance (cold engine):
Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.20 ±0.03 mm (0.008 ±0.001 in)
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.25 ±0.003 mm (0.010 ±0.001 in)
Valve timing:All except code NAEEngine code NAE
Inlet opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24¼ BTDC18¼ BTDC
Inlet closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64¼ ABDC58¼ ABDC
Exhaust opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70¼ BBDC70¼ BBDC
Exhaust closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18¼ ATDC6¼ ATDC
Lubrication system
Specifications as for 1.3 litre engine
Torque wrench settingsNmlbf ft
Specifications as for 1.3 litre engine except for the following:
Crankshaft pulley bolt:
Fuel injection models up to 1987 . . . . . . . . . . . . . . . . . . . . . . . . . . . .115 to 13085 to 96
Fuel injection models from 1987 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100 to 11574 to 85
SOHC engines 2A¥7
2A
The engine is of a four-cylinder, in-line,
single overhead camshaft type, mounted at
the front of the vehicle and available in 1.3,
1.6, 1.8 and 2.0 litre versions.
The crankshaft incorporates five main
bearings. Thrustwashers are fitted to the
centre main bearing in order to control
crankshaft endfloat.
The camshaft is driven by a toothed belt
and operates the slightly angled valves via
cam followers which pivot on ball-pins.
The auxiliary shaft which is also driven by
the toothed belt, drives the distributor, oil
pump and fuel pump.
The cylinder head is of crossflow design
with the inlet manifold mounted on the left-
hand side and the exhaust manifold mounted
on the right-hand side.
Lubrication is by means of a bi-rotor pump
which draws oil through a strainer located
inside the sump, and forces it through a full-
flow filter into the engine oil galleries where it
is distributed to the crankshaft, camshaft and
auxiliary shaft. The big-end bearings are
supplied with oil via internal drillings in the
crankshaft. The undersides of the pistons are
supplied with oil from drillings in the big-ends.
The distributor shaft is intermittently supplied
with oil from the drilled auxiliary shaft. The
camshaft followers are supplied with oil via adrilled spray tube from the centre camshaft
bearing.
A semi-closed crankcase ventilation system
is employed whereby piston blow-by gases
are drawn into the inlet manifold via an oil
separator and control valve.
Refer to Chapter 1, Section 8.
Refer to Chapter 1, Section 23.
Refer to Chapter 1, Section 35.
1When engine performance is poor, or if
misfiring occurs which cannot be attributed to
the ignition or fuel system, a compression test
can provide diagnostic clues. If the test is
performed regularly it can give warning of
trouble before any other symptoms become
apparent.2The engine must be at operating
temperature, the battery must be fully
charged and the spark plugs must be
removed. The services of an assistant will also
be required.
3Disable the ignition system by
disconnecting the coil LT feed. Fit the
compression tester to No 1 spark plug hole.
(The type of tester which screws into the
spark plug hole is to be preferred.)
4Have the assistant hold the throttle wide
open and crank the engine on the starter.
Record the highest reading obtained on the
compression tester.
5Repeat the test on the remaining cylinders,
recording the pressure developed in each.
6Desired pressures are given in the
Specifications. If the pressure in any cylinder
is low, introduce a teaspoonful of clean
engine oil into the spark plug hole and repeat
the test.
7If the addition of oil temporarily improves
the compression pressure, this indicates that
bore, piston or piston ring wear was
responsible for the pressure loss. No
improvement suggests that leaking or burnt
valves, or a blown head gasket, may be to
blame.
8A low reading from the two adjacent
cylinders is almost certainly due to the head
gasket between them having blown.
9On completion of the test, refit the spark
plugs and reconnect the coil LT feed.
5Compression test
4Crankcase ventilation system -
inspection and maintenance
3Valve clearances - checking and
adjustment
2Engine oil and filter - renewal
1General information
Page 8 of 24
The following operations can be carried out
without removing the engine from the vehicle:
a)Removal and servicing of the cylinder
head
b)Removal of the camshaft after removal of
the cylinder head
c)Removal of the timing belt and sprockets
d)Removal of the sump
e)Removal of the oil pump
f)Removal of the pistons and connecting
rods
g)Removal of the big-end bearings
h)Removal of the engine mountings
i)Removal of the clutch and flywheel
j)Removal of crankshaft front and rear oil
seals
k)Removal of the auxiliary shaft
The following operations can only be carried
out after removing the engine from the
vehicle:
a)Removal of the crankshaft main bearings
b)Removal of the crankshaft
The engine may be lifted out either on its
own, or together with the manual
gearbox/automatic transmission. Unless work
is to be carried out on the manual
gearbox/automatic transmission, it is
recommended that the engine is removed on
its own. Where automatic transmission is
fitted, the engine should where possible be
removed on its own due to the additional
weight of the transmission. Note: The air conditioning system should
always be discharged by a Ford dealer or air
conditioning specialist.
Note: Refer to the warning in Section 8 before
proceeding. A suitable hoist and lifting tackle
will be required for this operation.
1Disconnect the battery negative lead.
2Remove the bonnet.
3On carburettor models remove the air cleaner.
4On fuel injection models, disconnect the
crankcase ventilation hose from the air inlet
hose, then disconnect the air inlet hose from
the throttle body. Depress the locking clip on
the airflow meter wiring plug and disconnect
the plug (pulling on the plug, not the wiring)
then release the four securing clips and lift off
the air cleaner lid with the airflow meter and
air inlet hose.
5Remove the four retaining clips and
unscrew the two retaining screws, then
withdraw the upper section of the cooling fan
shroud from the radiator. Unclip and remove
the lower section of the shroud.
6Remove the thermo-viscous cooling fan as
described in Chapter 3.
7Drain the cooling system.
8Disconnect the upper radiator hose and
where applicable, the expansion tank hose
from the thermostat housing.
9Disconnect the coolant hoses from the
coolant pump, and where applicable from the
inlet manifold and automatic choke. Unclip
the coolant hose from the bracket on the
exhaust manifold hot air shroud/heat shield,
or the camshaft cover, as applicable.
10On carburettor models, where applicable
disconnect the vacuum pipe from the engine
management module.
11Disconnect the brake servo vacuum pipe
from the inlet manifold.
12On carburettor models, disconnect the fuel
hoses from the carburettor and where
applicable the mechanical fuel pump and plug
the ends of the hoses to minimise petrol
spillage. Remember to take adequate fire
precautions.
13On fuel injection models, disconnect the
fuel feed line from the fuel pressure regulator,
then disconnect the fuel supply hose from thefuel rail. Position a suitable container beneath
the pressure regulator, then slowly loosen the
fuel feed union to relieve the pressure in the
fuel lines before disconnecting the union.
Take adequate fire precautions. Plug the ends
of the hoses to minimise petrol spillage.
14Disconnect the throttle cable, and where
applicable remove its bracket.
15Disconnect the HT lead from the ignition
coil.
16Disconnect the wiring from the following
components as applicable depending on
model:
Alternator
Starter motor
Distributor
Oil pressure warning lamp switch
Temperature gauge sender
Engine coolant temperature sensor
Automatic choke
Automatic choke pull-down solenoid
Carburettor anti-dieselling valve
Inlet manifold heater
Carburettor stepper motor
Fuel injection harness
Dipstick
17Where applicable, detach the power
steering pump from the cylinder block and
move it to one side.
18Unscrew and remove the top engine-to-
gearbox bolts which are accessible from the
engine compartment. Note the location of the
earth strap on one of the bolts.
19Note the location of the earth strap on the
rear inlet manifold stud, then remove the nut
and disconnect the strap.
20Apply the handbrake (if not already done),
jack up the front of the vehicle and support on
axle stands (see ÒJacking and Vehicle SupportÓ).
21Drain the engine oil into a suitable
container.
22Remove the starter motor.
23Remove the exhaust downpipe.
24Unscrew the nuts or bolts, as applicable,
securing the engine mountings to the
crossmember. Recover the washers.
25Unscrew and remove the remaining
engine-to-gearbox bolts, and remove the bolt
from the engine adapter plate (see
illustration).
26Remove the two securing bolts and
disconnect the engine-to-gearbox brace from
the engine and gearbox.
27Working inside the vehicle, place a
wooden block under the clutch pedal to raise
it fully against its stop which will hold the
automatic adjuster pawl clear of the toothed
quadrant.
28Disconnect the clutch cable from the
clutch release arm, and pass the cable
through the bellhousing. Where applicable,
remove the clip securing the clutch cable to
the right-hand engine mounting bracket. Note
the cable routing for use when refitting.
29Lower the vehicle to the ground, and
support the gearbox with a trolley jack, using
a block of wood between the jack and the
gearbox to spread the load.
30Make a final check to ensure that all
relevant wires, pipes and hoses have been
disconnected to facilitate engine removal.
9Engine - removal leaving
manual gearbox in vehicle
8Method of engine removal
7Major operations requiring
engine removal
6Major operations possible with
the engine in the vehicle
2A¥8SOHC engines
9.25 Engine adapter plate bolt (A) and
engine-to-gearbox brace (B)
Warning: Vehicles equipped
with air conditioning:
Components of the air
conditioning system may
obstruct work being undertaken on the
engine, and it is not always possible to
unbolt and move them aside sufficiently,
within the limits of their flexible
connecting pipes. In such a case, the
system should be discharged by a Ford
dealer or air conditioning specialist. The
refrigerant is harmless under normal
conditions, but in the presence of a naked
flame (or a lighted cigarette) it forms a
highly toxic gas. Liquid refrigerant spilled
on the skin will cause frostbite. If
refrigerant enters the eyes, rinse them
with a diluted solution of boric acid and
seek medical advice immediately.
Page 11 of 24
4Check that the engine adapter plate is
correctly positioned on its locating dowels.
5Refit the propeller shaft.
6Refit the exhaust system.
7Reconnect the clutch cable to the release
arm, ensuring that it is routed as noted during
removal.
8Fill the engine with the correct grade and
quantity of oil.
9Fill the cooling system.
10Check and if necessary top-up the
gearbox oil level.
11Check and if necessary adjust the tension
of the alternator and where applicable the
power steering pump drivebelt(s).
12Adjust the throttle cable.
1Reverse the removal procedure described
in Section 12, noting the following points.
2Check that the engine adapter plate is
correctly positioned on its locating dowels.
3As the torque converter is only loosely
engaged in the transmission, care must be
taken to prevent the torque converter from
falling out forwards. When the torque
converter hub is fully engaged with the fluid
pump drivegear in the transmission, distance
ÒAÓ in illustration 2.24 of Chapter 7B must be
as shown. Incorrect installation of the torque
converter will result in damage to the
transmission.
4As the engine and transmission are
reconnected, guide the torque converter studs
through the holes in the driveplate, noting that
on the C3 type transmission, the torque
converter fluid drain plug must line up with the
opening in the driveplate (see illustration 2.25
in Chapter 7B). When the engine is positioned
flush with the engine adapter plate and the
transmission housing, check that the torque
converter is free to move axially a small
amount before refitting and tightening the
engine-to-transmission bolts.
5Do not tighten the torque converter-to-
driveplate nuts until the lower engine-to-
transmission bolts have been fitted and
tightened.
6Reconnect and adjust the selector rod.
7Refit the propeller shaft.8Refit the exhaust system.
9Fill the engine with the correct grade and
quantity of oil.
10Fill the cooling system.
11Check and if necessary top-up the
transmission fluid level.
12Check and if necessary adjust the tension
of the alternator and where applicable the
power steering pump drivebelt(s).
13Adjust the throttle cable.
14If applicable, adjust the kickdown cable.
1The engine mountings incorporate
hydraulic dampers and must be renewed if
excessive engine movement is evident.
2Working in the engine compartment,
unscrew the central nuts securing the engine
mounting brackets to the tops of the
mountings. Recover the washers where
applicable.
3Remove the two bolts or the central nut and
washer (as applicable) in each case securing
the mountings to the crossmember.
4Raise the engine using a hoist and lifting
tackle attached to the engine lifting brackets on
the cylinder head, or a jack with an interposed
block of wood under the sump, until the
mountings can be withdrawn (see illustration).
5Fit the new mountings, then lower the
engine onto them.
6Fit the bolts or the nuts and washers (as
applicable) securing the mountings to the
crossmember, and tighten them.
7Fit and tighten the central nuts, and washers
if applicable, securing the engine mounting
brackets to the tops of the mountings.
Dismantling
1It is best to mount the engine on a
dismantling stand but if this is not available,
stand the engine on a strong bench at a
comfortable working height. Failing this, it will
have to be stripped down on the floor.
2Cleanliness is most important, and if theengine is dirty, it should be cleaned with
paraffin while keeping it in an upright position.
3Avoid working with the engine directly on a
concrete floor, as grit presents a real source
of trouble.
4As parts are removed, clean them in a
paraffin bath. However, do not immerse parts
with internal oilways in paraffin as it is difficult
to remove, usually requiring a high pressure
hose. Clean oilways with nylon pipe cleaners.
5It is advisable to have suitable containers
available to hold small items according to
their use, as this will help when reassembling
the engine and also prevent possible losses.
6Always obtain a complete set of new
gaskets for use during engine reassembly, but
retain the old gaskets with a view to using
them as a pattern to make a replacement if a
new one is not available.
7Where possible, refit securing nuts, bolts and
washers to their locations after removing the
relevant components. This will help to protect
the threads and will also prevent losses.
8Retain unserviceable components in order
to compare them with the new parts supplied.
9Suitable splined sockets will be required for
removal of the oil pump bolts, the timing belt
tensioner bolts on early models (up to mid-
1985), and the cylinder head bolts on early
models (up to early 1984) and a size T55 Torx
socket will be required to remove the cylinder
head bolts on later models (from early 1984).
10Before dismantling the main engine
components the following externally mounted
ancillary components can be removed, with
reference to the relevant Chapters of this
Manual and the relevant Sections of this
Chapter, where applicable:
Inlet manifold (and carburettor, where
applicable
Exhaust manifold
Fuel pump and operating pushrod (where
applicable)
Alternator
Distributor, HT leads and spark plug
Coolant pump, thermostat and housing
Temperature gauge sender and oil pressure
warning lamp switch
Oil filter
Dipstick
Engine mounting brackets (see illustration)
Crankcase ventilation valve and oil separator
Clutch
Alternator mounting bracket (see illustration)
18Engine dismantling,
examination, renovation and
reassembly - general information
17Engine mountings - renewal
16Engine/automatic
transmission assembly -
reconnection and refitting
SOHC engines 2A¥11
2A
18.10b Removing the alternator mounting
bracket18.10a Removing the right-hand engine
mounting bracket
17.4 Withdrawing an engine mounting
Page 24 of 24
components, but there must be no tight spots
or binding.
28Check that the crankshaft endfloat is
within the specified limits by inserting a feeler
blade between the centre crankshaft web and
the thrustwashers.
29Make sure that the rear oil seal is fully
located onto its seating. Coat the rear main
bearing cap sealing wedges with sealing
compound, then press them into position
using a blunt screwdriver with the rounded
red face towards the cap (see illustration).
30Refit the oil pump and pick-up tube.
31Refit the crankshaft front oil seal housing
and the auxiliary shaft front cover using a new
gasket, and tighten the securing bolts. Smear
the lip of the oil seal with clean engine oil
before fitting; and using a straight edge, ensure
that the bottom face of the oil seal housing is
aligned with the bottom face of the cylinder
block before finally tightening the bolts.
32Refit the pistons and connecting rods.
33Refit the flywheel/driveplate and the
auxiliary shaft sprocket, crankshaft sprocket,
and timing belt.
1Examine the bearing surfaces of the
crankshaft for scratches or scoring and, using
a micrometer, check each journal and
crankpin for ovality. Where this is found to be
in excess of 0.0254 mm (0.001 in) the
crankshaft will have to be reground and
undersize bearings fitted.
2Crankshaft regrinding should be carried out
by a suitable engineering works, who will
normally supply the matching undersize main
and big-end shell bearings.
3Note that undersize bearings may already
have been fitted, either in production or by a
previous repairer. Check the markings on the
backs of the old bearing shells, and if in doubt
take them along when buying new ones.
Production undersizes are also indicated by
paint marks as follows:
White line on main bearing cap - parent bore
0.40 mm oversize
Green line on crankshaft front counterweight
- main bearing journals 0.25 mm
undersize
Green spot on counterweight - big-end
bearing journals 0.25 mm undersize4If the crankshaft endfloat is more than the
maximum specified amount, new
thrustwashers should be fitted to the centre
main bearings. These are usually supplied
together with the main and big-end bearings
on a reground crankshaft.
5An accurate method of determining bearing
wear is by the use of Plastigage. The
crankshaft is located in the main bearings
(and big-end bearings if necessary) and the
Plastigage filament located across the journal
which must be dry. The cap is then fitted and
the bolts/nuts tightened to the specified
torque. On removal of the cap the width of the
filaments is checked against a scale which
shows the bearing running clearance. This
clearance is then compared with that given in
the Specifications (see illustration).
6If the spigot bearing in the rear of the
crankshaft requires renewal, extract it with a
suitable puller. Alternatively fill it with heavy
grease and use a close fitting metal dowel
driven into the centre of the bearing. Drive the
new bearing into the crankshaft with a soft
metal drift.
1The cylinder bores must be examined for
taper, ovality, scoring and scratches. Start by
examining the top of the bores; if these are
worn, a slight ridge will be found which marks
the top of the piston ring travel. If the wear is
excessive, the engine will have had a high oil
consumption rate accompanied by blue
smoke from the exhaust.
2If available, use an inside dial gauge to
measure the bore diameter just below the
ridge and compare it with the diameter at the
bottom of the bore, which is not subject to
wear. If the difference is more than 0.152 mm
(0.006 in), the cylinders will normally require
reboring with new oversize pistons fitted.
3Proprietary oil control rings can be obtained
for fitting to the existing pistons if it is felt that
the degree of wear does not justify a rebore.
However, any improvement brought about by
such rings may be short-lived.
4If new pistons or piston rings are to be fitted
to old bores, deglaze the bores with abrasive
paper or a Òglaze busterÓ tool. The object is to
produce a light cross-hatch pattern to assistthe new rings to bed in.
5If there is a ridge at the top of the bore and
new piston rings are being fitted, either the
top piston ring must be stepped (Òridge
dodgerÓ pattern) or the ridge must be
removed with a ridge reamer. If the ridge is
left, the piston ring may hit it and break.
6Thoroughly examine the crankcase and
cylinder block for cracks and damage and use
a piece of wire to probe all oilways and
waterways to ensurethatthey are
unobstructed.
1Make a final check to ensure that
everything has been reconnected to the
engine and that no rags or tools have been left
in the engine bay.
2Check that oil and coolant levels are
correct.
3Start the engine. This may take a little
longer than usual as fuel is pumped up to the
engine.
4Check that the oil pressure light goes out
when the engine starts.
5Run the engine at a fast tickover and check
for leaks of oil, fuel or coolant. Also check
power steering and transmission fluid cooler
unions, where applicable. Some smoke and
odd smells may be experienced as assembly
lubricant burns off the exhaust manifold and
other components.
6Bring the engine to normal operating
temperature, then check the ignition timing
and the idle speed (where applicable) and
mixture.
7If splined type cylinder head bolts have
been used, stop the engine after it has been
running for 15 minutes, then remove the
crankshaft cover and tighten the cylinder
head bolts to the fourth stage given in the
Specifications, in the correct order.
8When the engine has completely cooled,
re-check the oil and coolant levels, and
check, and if necessary adjust, the valve
clearances.
9If new bearings, pistons etc have been
fitted, the engine should be run-in at reduced
speeds and loads for the first 500 miles (800
km) or so. It is beneficial to change the engine
oil and filter after this mileage.
37Initial start-up after overhaul or
major repair
36Cylinder block and bores -
examination and renovation35Crankshaft and bearings -
examination and renovation
2A¥24SOHC engines
34.24 Fitting a thrustwasher to the centre
main bearing cap35.5 Checking the width of the filament
against the scale of the packet34.29 Fitting a sealing wedge to the rear
main bearing cap