OPEL VECTRA 1988 Service Repair Manual
Manufacturer: OPEL, Model Year: 1988, Model line: VECTRA, Model: OPEL VECTRA 1988Pages: 525, PDF Size: 58.26 MB
Page 221 of 525

23Cylinder head - inspection
and renovation
4
Note: Refer to a dealer for advice before
attempting to carry out valve grinding or valve
seat reciting operations, as these operations
may not be possible for the DIY mechanic.
This is due to the fitment of hardened valve
seats for use with unleaded petrol
Inspection
1Remember that the cylinder head is of light
alloy construction and is easily damaged, use
a blunt scraper or rotary wire brush to clean all
traces of carbon deposits from the
combustion spaces and the ports. The valve
stems and valve guides should also be freed
from any carbon deposits. Wash the
combustion spaces and ports down with
paraffin and scrape the cylinder head surface
free of any foreign matter with the side of a
steel rule, or a similar article.
2If the engine is installed in the car, clean the
pistons and the top of the cylinder bores. If
the pistons are still in the block, it is essential
that great care is taken to ensure that no
carbon gets into the cylinder bores. This could
scratch the cylinder walls or cause damage to
the pistons and rings. To ensure this does not
happen, first turn the crankshaft so that two of
the pistons are at the top of their bores. Insert
rag into the other two bores or seal them off
with paper and masking tape. The waterways
should also be covered with small pieces of
masking tape, to prevent particles of carbon
entering the cooling system and damaging the
coolant pump.
3Press a little grease into the gap between
the cylinder walls and the two pistons that are
to be worked on. With a blunt scraper,
carefully scrape away the carbon from the
piston crown, taking great care not to scratch
the aluminium. Also scrape away the carbon
from the surrounding lip of the cylinder wall.
When all carbon has been removed, scrape
away the grease that will now be
contaminated with carbon particles, taking
care not to press any into the bores. To assist
prevention of carbon build-up, the piston
crown can be polished with a metal polish.
Remove the rags or masking tape from the
other two cylinders, and turn the crankshaft
so that the two pistons that were at thebottom are now at the top. Place rag or
masking tape in the cylinders that have been
decarbonised, and continue as just described.
4Examine the heads of the valves for pitting
and burning, especially the heads of the
exhaust valves. The valve seatings should be
examined at the same time. If the pitting on
the valve and seat is very slight, the marks
can be removed by grinding the seats and
valves together with coarse, and then fine,
valve grinding paste.
5Where bad pitting has occurred to the valve
seats, it will be necessary to recut them and fit
new valves. This latter job should be entrusted
to the local dealer or engineering works. In
practice it is very seldom that the seats are so
badly worn. Normally it is the valve that is too
badly worn for refitting, and the owner can
easily buy a new set of valves and match
them to the seats by valve grinding.
Renovation
6Valve grinding is carried out as follows.
Smear a trace of coarse carborundum paste
on the seat face and apply a suction grinder
tool to the valve head. With a semi-rotary
motion, grind the valve head to its seat, lifting
the valve occasionally to redistribute the
grinding paste. When a dull matt even surface
is produced on both the valve seat and the
valve, wipe off the paste and repeat the
process with fine carborundum paste, lifting
and turning the valve to redistribute the paste
as before. A light spring placed under the
valve head will greatly ease this operation.
When a smooth unbroken ring of light grey
matt finish is produced, on both valve and
valve seat faces, the grinding operation is
complete. Carefully clean away every trace of
grinding compound, taking great care to leave
none in the ports or in the valve guides. Clean
the valves and valve seats with a
paraffin-soaked rag, then with a clean rag,
and finally, if an air line is available, blow the
valves, valve guides and valve ports clean.
7Check that all valve springs are intact. If any
one is broken, all should be renewed. Check
the free height of the springs against new
ones. If some springs are not long enough,
replace them all. Springs suffer from fatigue
and it is a good idea to renew them even if
they look serviceable. 8The cylinder head can be checked for
warping either by placing it on a piece of plate
glass or using a straight-edge and feeler
blades. If there is any doubt or if its block face
is corroded, have it re-faced by your dealer or
motor engineering works.
9On 1.8 and 2.0 litre, always renew the
sealing ring between the cylinder head and
the thermostat housing when the head is
removed for overhaul (see illustration).
Reference to Chapter 21 will show that a
considerable amount of work is involved if it is
wished to renew the sealing ring with the
cylinder head installed.
10If the oil pressure regulating valve in the
cylinder head is to be renewed, access is
gained through the circular plug covering the
end of the valve (see illustration). The old
valve must be crushed, then its remains
extracted, and a thread (M10) cut in the valve
seat to allow removal using a bolt. A new
valve and plug can then be driven into
position. In view of the intricacies of this
operation, it is probably best to have the valve
renewed by a Vauxhall dealer if necessary.
24Hydraulic valve lifters -
inspection
4
Inspection
1On engines that have covered a high
mileage, or for which the service history
(particularly oil changes) is suspect, it is
possible for the valve lifters to suffer internal
contamination. In extreme cases this may
result in increased engine top end noise and
wear. To minimise the possibility of problems
occurring later in the life of the engine, it is
advisable to dismantle and clean the hydraulic
valve lifters as follows whenever the cylinder
head is overhauled. Note that no spare parts
are available for the valve lifters, and if any of
the components are unserviceable, the
complete assembly must be renewed (see
illustration).
2With the cylinder head removed and
dismantled as described in Sections 21 and
23, first inspect the valve lifter bores in the
2A•24SOHC engine procedures
23.10 Oil pressure regulating valve (1) and
plug (2) - 2.0 litre engine23.9 Renewing the thermostat housing
sealing ring - 2.0 litre engine
Warning: The exhaust valves
fitted to 20 XEJ and C 20 XE
(DOHC) models are fitted with
sodium to improve their heat
transfer. Sodium is a highly reactive
metal, which will ignite or explode
spontaneously on contact with water
(including water vapour in the air). These
must NOT be disposed of with ordinary
scrap. Seek advice from a Vauxhall dealer
or your Local Authority, if the valves are to
be disposed of.
Page 222 of 525

cylinder head for wear. If excessive wear is
evident, the cylinder head must be renewed.
Also check the valve lifter oil holes in the
cylinder head for obstructions.
3Starting with number 1 valve lifter, carefully
pull the collar from the top of the valve lifter
cylinder. It should be possible to remove the
collar by hand -if a tool is used, take care not
to distort the collar.
4Withdraw the plunger from the cylinder, and
recover the spring.5Using a small screwdriver, carefully prise
the cap from the base of the plunger. Recover
the spring and ball from under the cap, taking
care not to lose them as the cap is removed.
6Carefully clean all the components using
paraffin or solvent, paying particular attention
to the machined surfaces of the cylinder
(internal surfaces), and piston (external
surfaces). Thoroughly dry all the components
using a lint-free cloth. Carefully examine the
springs for damage or distortion -thecomplete valve lifter must be renewed if the
springs are not in perfect condition.
7Lubricate the components sparingly with
clean engine oil of the correct grade, then
reassemble as follows.
8Invert the plunger, and locate the ball on its
seat in the base of the plunger (see
illustration).
9Locate the smaller spring on its seat in the
plunger cap, then carefully refit the cap and
spring, ensuring that the spring locates on the
ball. Carefully press around the flange of the
cap, using a small screwdriver if necessary,
until the flange is securely located in the
groove in the base of the plunger (see
illustrations).
10Locate the larger spring over the plunger
cap, ensuring that the spring is correctly
seated, and slide the plunger and spring
assembly into the cylinder (see illustrations).
11Slide the collar over the top of the
plunger, and carefully compress the plunger
by hand, until the collar can be pushed down
to engage securely with the groove in the
cylinder (see illustration).
12Repeat the above procedures on the
remaining valve lifters.
SOHC engine procedures 2A•25
24.11 Slide the collar (1) over the top of
the plunger and engage with the
groove (2) in the cylinder24.10B . . .then slide the plunger and
spring assembly into the cylinder
24.9B Locate the cap flange in the plunger
groove24.9A Spring (1) located in plunger cap,
and ball (2) located on seat in plunger
24.10A Locate the spring over the
plunger cap . . .
24.8 Locate the ball (1) on it’s seat (2) in the base of the plunger24.1 Hydraulic valve lifter components - SOHC engines
1 Collar
2 Plunger3 Ball
4 Small spring5 Plunger cap
6 Large spring7 Cylinder
2A
Page 223 of 525

25Flywheel -removal, inspection
and refitting
4
Note: New flywheel securing bolts must he
used on refitting. Certain models are fitted
with a ‘Pot type’ flywheel. Although, it has a
deeply recessed surface for the clutch disc,
the operations below are the same.
Removal
1If not already done, remove the clutch,
(Chapter 6), and the starter motor, (Chapter 5).
2If the engine is in the vehicle, remove the
clutch release bearing and its guide sleeve, as
described in Chapter 6.
3Although the flywheel bolt holes are offset
so that the flywheel can only be fitted in one
position, it will make refitting easier if
alignment marks are made between the
flywheel and the end of the crankshaft.
4Prevent the flywheel from turning by
jamming the ring gear teeth using a large
screwdriver or similar tool. Access is most
easily obtained through the starter motor
aperture if the engine is in the vehicle.
5Unscrew the securing bolts, and remove
the flywheel (see illustration). Take care, as
the flywheel is heavy!
Inspection
6With the flywheel removed, it can be
inspected as follows.
7If the teeth on the flywheel starter ring are
badly worn, or if some are missing, then it will
be necessary to remove the ring and fit a new
one.
8The old ring can be split with a cold chisel,
after making a cut with a hacksaw blade
between two gear teeth. Take great care not
to damage the flywheel during this operation,
and use eye protectors always. Once the ring
has been split, it will spread apart and can be
lifted from the flywheel.
9The new ring gear must be heated to 180 to
230°C (356 to 446°F) and unless facilities for
heating by oven or flame are available, leave
the fitting to a dealer or motor engineering
works. The new ring gear must not be
overheated during this work, or the temper of
the metal will be altered.10The ring should be tapped gently down
onto its register, and left to cool naturally -the
contraction of the metal on cooling will ensure
that it is a secure and permanent fit.
11If the clutch friction disc contact surface
of the flywheel is scored, or on close
inspection, show’s evidence of small hairline
cracks (caused by overheating), it may be
possible to have the flywheel surface ground.
This is provided that the overall thickness of
the flywheel is not reduced too much. Consult
a specialist engine repairer and if it is not
possible, renew the flywheel complete.
Refitting
12Refitting is a reversal of removal,
remembering the following points.
13Align the previously made marks on the
flywheel and crankshaft, and fit new flywheel
securing bolts. Tighten them to the specified
torque in the two stages given in the Specifi-
cations, whilst preventing the flywheel from
turning, as during removal (see illustrations).
14Where applicable, refit the clutch release
bearing, guide sleeve, and the clutch, as
described in Chapter 6.
26Flexplate (automatic
transmission) -removal and
refitting
4
Removal
1Remove the transmission (Chapter 7B).
2Prevent the flexplate from turning by
jamming its ring gear teeth using a large
screwdriver or similar tool.
3Unbolt and remove the flexplate. Examine
the bolts and renew them all as a set if there is
the slightest doubt about their condition.
4The ring gear can be checked, and renewed
if necessary, as described in Section 25.
Refitting
5Refitting is the reverse of the removal
procedure. If the bolts are to be re-used, use a
wire brush to clean their threads, apply a few
drops of thread-locking compound (Vauxhall
Part No 90167347, or equivalent) to the
threads of each bolt on refitting. Tighten the
bolts to the specified torque wrench setting.6Refit the transmission, refer to Chapter 7B if
necessary.
27Crankshaft front oil seal -
renewal
3
Renewal
1Remove the timing belt and the rear timing
belt cover, as described in Section 11.
2Ensure that the Woodruff key is removed
from the end of the crankshaft.
3Punch or drill a small hole in the centre of
the now-exposed oil seal. Screw in a
self-tapping screw, and pull on the screw with
pliers to extract the seal. Several attempts
may be necessary. Be careful not to damage
the sealing face of the crankshaft.
4Clean the oil seal seat with a wooden or
plastic scraper.
5Before fitting the new oil seal, steps must
be taken to protect the oil seal lips from
damage, and from turning back on the
shoulder at the front end of the crankshaft.
Grease the seal lips, and then wind tape
around the end of the crankshaft to form a
gentle taper.
6Tap the seal into position using a large
socket or tube, until the seal is flush with the
outer face of the oil pump housing.
7Refit the rear timing belt cover and the
timing belt tension the timing belt as
described in Section 11.
2A•26SOHC engine procedures
25.13C . . .and then through the
specified angle -
1.6 litre engine25.13B Tighten the flywheel securing bolts
to the specified toque . . .25.13A Tool for locking flywheel fitted to
engine-to-transmission bolt hole -
1.6 litre engine
25.5 Removing the flywheel -
1.6 litre engine
Page 224 of 525

28Crankshaft rear oil seal -
renewal
4
Renewal
1With the engine removed from the vehicle,
remove the flywheel, or flexplate (as
applicable) as described in Sections 25 and
26.
2Punch or drill a small hole in the centre of
the now-exposed oil seal. Screw in a
self-tapping screw, and pull on the screw with
pliers to extract the seal. Several attempts
may be necessary. Be careful not to damage
the sealing face of the crankshaft.
3Clean the oil seal seat with a wooden or
plastic scraper.4Grease the lips of the new seal, then tap the
seal into position using a tube, until flush with
the outer faces of the cylinder block and rear
main bearing cap (see illustration).
5Refit the flywheel or flexplate (if applicable),
as described in Sections 25 or 26.
29Sump - removal and refitting
4
Note: The sump gasket(s) must be renewed
on refitting and sealer will be required for use
on the oil pump and rear main bearing
cap-to-cylinder block joints
Removal
1If the engine is in the vehicle, continue as
follows, otherwise go on to paragraph 9.
2Disconnect the battery negative lead.
3Drain the engine oil, referring to Chapter 1 if
necessary, then refit and tighten the drain
plug.
4Apply the handbrake, then jack up the front
of the vehicle, and support securely on axle
stands (see “Jacking and Vehicle Support”).
5Remove the front section of the exhaust
system, as described in Chapter 4C.
6Where applicable, disconnect the wiring
from the oil level sensor.
7Unscrew the securing bolts and remove the
engine-to-transmission blanking plate from
the bellhousing.8Remove the securing bolts, and withdraw
the sump. Note that on most models, the
sump baffle will probably be pulled away from
the cylinder block with the sump, but cannot
be removed until the oil pick-up pipe has been
removed.
9On 1.6, 1.8 and 2.0 litre models, to remove
the sump baffle, it is necessary to unbolt the
bracket securing the oil pick-up pipe to the
cylinder block. The baffle can then be
manipulated over the oil pick-up pipe. On C
16 NZ2, 1.8 and 2.0 litre models, prise the
rubber gasket from the sump baffle.
10If need be, the oil pick-up pipe can be
removed by unscrewing the single bolt
securing the support bracket to the cylinder
block (if not already done). Then remove the
two bolts securing the end of the pipe to the
oil pump. Recover the O-ring.
11Clean all traces of old gasket and sealing
compound from the mating faces of the
cylinder block, sump baffle (where
applicable), and sump.
Refitting
12Begin refitting by applying sealing
compound (Vauxhall part No 90485251 or
equivalent) to the joints between the oil pump
and cylinder block, and the rear main bearing
cap and cylinder block (see illustrations).
13On C 16 NZ2, 1.8 and 2.0 litre locate a
new rubber gasket over the sump baffle
flange, ensuring that it is seated correctly (see
illustration).
14On 1.6, 1.8 and 2.0 litre models, offer the
sump baffle up to the cylinder block,
manipulating it over the oil pick-up pipe where
applicable.
15If the oil pick-up pipe has been removed,
refit it to the oil pump using a new O-ring and
tighten bolts to the specified torque (see
illustrations).
16Where applicable, refit the bracket
securing the oil pick-up pipe to the cylinder
block, ensuring that it passes through the
relevant hole in the sump baffle, if applicable
(see illustration).
17Coat the sump securing bolts with
thread-locking compound (i.e. Vauxhall part
No. 90167347), then refit the sump, and
tighten the bolts to the specified torque (see
illustrations).
SOHC engine procedures 2A•27
29.12B Applying sealing compound to the
joint between the oil pump and cylinder
block - 2.0 litre engine
29.15B . . .and tighten the securing bolts
to the specified torque - 2.0 litre engine29.15A Fit a new O-ring to the oil pick-up
pipe . . .29.13 Locate a new rubber gasket over
the sump baffle flange - 2.0 litre engine
29.12A Apply sealing compound (arrowed)
to oil pump and rear main bearing cap
joints before refitting sump
28.4 Fitting a new crankshaft rear oil seal -
2.0 litre engine
2A
Page 225 of 525

18If the engine is in the vehicle, further
refitting is a reversal of the removal
procedure, but refit the front section of the
exhaust system referring to Chapter 4C. On
completion, refill the engine with oil, as
described in Chapter 1.
30Oil pump - removal and
refitting
4
Removal
1Remove the timing belt, sprockets and the
rear timing belt cover, as shown in Section 11.
2Remove the sump, oil pick-up pipe and
sump baffle (where applicable), as described
in Section 29.3On C 16 NZ2, 1.8 and 2.0 litre engines,
unscrew the oil filter from its mounting on the
oil pump, referring to Chapter 1, if necessary.
4Disconnect the wiring from the oil pressure
switch mounted on the oil pump.
5Remove the securing bolts, and withdraw
the oil pump from the cylinder block. Recover
the gasket.
6The oil pump can be dismantled for
inspection, as described in Section 31.
Refitting
7Thoroughly clean the mating faces of the oil
pump and cylinder block, then locate a new
gasket on the block (see illustration).
8Before refitting the oil pump, steps must be
taken to protect the oil seal lips from damage,
and from turning back on the shoulder at the
front end of the crankshaft. Grease the seallips, and then wind tape around the
crankshaft to form a gentle taper.
9Refit the oil pump, ensuring that the inner
gear engages with the flats on the crankshaft,
and tighten the securing bolts to the specified
torque, then remove the tape from the end of
the crankshaft (see illustrations).
10Reconnect the wiring to the oil pressure
switch.
11On C 16 NZ2, 1.8 and 2.0 litre engines, fit
a new oil filter, with reference to Chapter 1.
12Refit the sump baffle (where applicable),
oil pick-up tube and sump, as described in
Section 29.
13Refit the rear timing belt cover and the
timing belt, and tension the timing belt as
described in Section 11.
31Oil pump - dismantling,
inspection and reassembly
4
Note: A new crankshaft front oil seal must be
used on reassembly
Dismantling
1With the oil pump removed as described in
Section 30, continue as follows.
2Remove the securing screws and withdraw
the rear cover (see illustration). The screws
may be very tight, in which case it may be
necessary to use an impact driver to remove
them.
2A•28SOHC engine procedures
29.16 Refitting the oil pick-up pipe bracket
- 2.0 litre engine29.17B Refitting the sump - 2.0 litre engine
31.2 Removing an oil pump rear cover
securing screw -
2.0 litre SOHC engine30.9C Tighten the oil pump securing bolts
to the specified torque -
2.0 litre SOHC engine30.9B . . .and with two flats (arrowed) on
1.8 and 2.0 litre engines
30.9A Oil pump inner gear must engage
with hexagon flats on crankshaft (arrowed)
on 1.4 and 1.6 litre engines . . .30.7 Fit a new oil pump gasket to the
cylinder block - 2.0 litre engine
29.17A Coat the sump securing bolts with
thread-locking compound before fitting
Page 226 of 525

Inspection
3Check the clearance between the inner and
outer gear teeth (backlash) using a feeler
blade (see illustration).
4Check the clearance between the edges of
the gears and the housing (endfloat) using a
straight edge and a feeler blade (see
illustration).
5If any of the clearances are outside the
specified limits, renew the components as
necessary.
6Ensure that the gears and the interior of the
pump body are scrupulously clean before
reassembly, and note that the outer gear is
marked with a punch dot to indicate the gear
outer face.
7The oil pressure relief valve components
can be removed from the pump by
unscrewing the cap (see illustration).
Examine the spring and plunger, and renew if
necessary.
Reassembly
8Thoroughly clean the components before
refitting.
9Always renew the crankshaft front oil seal at
the front of the oil pump housing. Prise out the
old seal using a screwdriver, and fit the new
seal using a socket or tube, so that it is flush
with the outer face of the housing (see
illustrations).
10Ensure that the mating faces of the rear
cover and the pump housing are clean, then
coat the pump housing mating face with
sealing compound (Vauxhall part No
90485251, or equivalent) and refit the rear
cover. Refit and tighten the securing screws.
11Refit the pump, as described in Section 30.
32Pistons and connecting rods
- removal and refitting
4
Note: New big-end cap bolts must be used on
refitting
Removal
1Remove the cylinder head, as described
previously in Section 20.
2Remove the sump, oil pick-up pipe and
sump baffle (where applicable), as described
in Section 29.3If the connecting rods and big-end caps are
not marked to indicate their positions in the
cylinder block (i.e. cylinder numbers),
centre-punch them at adjacent points either
side of the cap/rod joint. Note to which side of
the engine the marks face (see illustration).
4Unscrew the big-end cap bolts from the
first connecting rod, and remove the cap. If
the bearing shells are to be re-used, tape the
cap and shell together.
5Check the top of the piston bore for a wear
ridge. If evident, carefully scrape it away with
a ridge reaming tool, otherwise as the piston
is pushed out of the block, the piston rings
may jam against the ridge.
6Place the wooden handle of a hammer
against the bottom of the connecting rod, and
push the piston/rod assembly up and out of the
cylinder bore. Recover the bearing shell, and
tape it to the connecting rod if it is to be re-used.
7Remove the remaining three assemblies in
a similar way. Rotate the crankshaft as
necessary to bring the big-end bolts to the
most accessible position.
8The piston can be separated from the
connecting rod by removing the circlips that
secure the fully floating gudgeon pin. Note the
orientation of the piston and connecting rod
before separation, and if necessary, make
alignment marks. Reassembly is a reversal of
dismantling ensuring that the piston and
connecting rod are correctly orientated.
9The pistons and connecting rods can be
examined for wear and damage, as described
in Section 33, and the bearings can be
examined as described in Section 35.
Refitting
10Begin reassembly by laying the
piston/connecting rod assemblies out in their
correct order, complete with bearing shells,
ready for refitting into their respective bores in
the cylinder block.
11Ensure that the seats for the bearing
shells are absolutely clean, and then fit the
shells into the seats.
12Wipe out the cylinder bores and oil them.
Oil the piston rings liberally, and ensure that
the ring gaps are positioned as described in
Section 33.
13Fit a piston ring compressor tool to the
first assembly to be installed.
SOHC engine procedures 2A•29
31.7 Oil pressure relief valve components
- 2.0 litre SOHC engine
32.3 Big-end cap centre punch
identification marks (circled). Note that lug
on bearing cap faces flywheel end of
engine - 2.0 litre SOHC engine
31.9B . . .and fit the new seal using a
socket - 2.0 litre SOHC engine31.9A Prise out the old crankshaft front
oil seal . . .
31.4 . . .and between the edges of the
gears and the housing -
2.0 litre SOHC engine31.3 Check the clearance between the
inner and outer gear teeth . . .
2A
Page 227 of 525

14Insert the rod and piston into the top of
the cylinder bore, so that the base of the
compressor stands on the block. Check that
the connecting rod markings are towards the
side of the engine noted during removal. Note
that the arrow or notch, as applicable, on the
piston crown should point towards the timing
belt end of the engine, and the lugs on the
connecting rods should point towards the
flywheel end of the engine (see illustrations).
15Apply the wooden handle of a hammer to
the piston crown and tap the assembly into
the bore, at the same time releasing the
compressor (see illustration).
16Oil the relevant crankpin, then guide the
big-end of the connecting rod near to the
crankpin, and pull it firmly onto the crankpin.
Ensure that the bearing shell remains in
position in the connecting rod.
17Fit the big-end cap, with the markings
towards the side of the engine noted during
removal (see illustration). Note that the lug
should point towards the flywheel end of the
engine.
18Fit new big-end cap bolts, and tighten
them to the specified torque in the two stages
given in the Specifications (see illustrations).
19Repeat the procedure on the remaining
three assemblies.
20Refit the sump baffle (where applicable),
oil pick-up pipe and sump, as described in
Section 29.
21Refit the cylinder head, as described
previously in this Section 20.
33Pistons and connecting rods
-examination and renovation
4
Examination
1Examine the mating faces of the big-end
caps to see if they have ever been filed, in a
mistaken attempt to take up bearing wear.
This is extremely unlikely, but if evident, the
offending connecting rods and caps must be
renewed.
2Check the alignment of the rods visually,
and if all is not well, take the rods to a
Vauxhall dealer for a more detailed check.
3The gudgeon pins are an interference
(shrink) fit in the connecting rod small ends.
Separation of the pistons and rods is a job for
a dealer due to the special tools required, asis any remedial action required if the gudgeon
pin is no longer an interference fit in the rod.
4Examine the pistons for ovality, scoring and
scratches.
5If new rings are to be fitted to the existing
pistons, expand the old rings over the tops of
the pistons. The use of two or three old feeler
blades will be helpful in preventing the rings
dropping into empty grooves. Note that the oil
control ring is in three sections, and note
which way up each ring is fitted, for use when
refitting (see illustrations).
Renovation
6Before fitting the new rings to the pistons,
insert them into their relevant cylinder bores,
and check that the ring end gaps are within the
specified limits using a feeler blade (see
illustration). Check the ring gaps at the upper
and lower limits of the piston travel in the bores.
2A•30SOHC engine procedures
32.14A Piston crown arrow must point
towards timing belt end of engine -
1.6 litre engine32.14C Lugs (arrowed) on connecting rod
and big-end cap must point towards
flywheel end of engine - 1.6 litre engine
33.5A Using a feeler blade to aid removal
of a piston ring - 2.0 litre SOHC engine32.18B . . .then through the specified
angle - 2.0 litre SOHC engine32.18A Tighten the big-end cap bolts to
the specified torque . . .
32.17 Fitting a big-end bearing cap -
2.0 litre SOHC engine32.15 Tapping a piston into its bore -
2.0 litre SOHC engine
32.14B . . .and similarly for the 2.0 litre
SOHC engine
Page 228 of 525

7If any of the ring end gaps exceed the
specified tolerance, the relevant rings will have
to be renewed, and if the ring grooves in the
pistons are worn, new pistons may be required.
8Clean out the piston ring grooves using a
piece of old piston ring as a scraper. Take
care not to scratch the surface of the pistons.
Protect your fingers, piston ring edges are
sharp. Also probe the groove oil return holes,
to ensure that they are not blocked.
9Check the cylinder bores for signs of wear
ridges towards the top of the bores. If wear
ridges are evident, and new piston rings are
being fitted, the top ring must be stepped to
clear the wear ridge, or the bore must be
de-ridged using a scraper.
10Fit the oil control ring sections with the
lower steel ring gap offset 25 to 50 mm to the
right of the spreader ring gap, and the upper
steel ring gap offset by the same distance to
the left of the spreader ring gap.
11Fit the lower compression ring, noting that
the ring is tapered or stepped. The ring should
be fitted with the word “TOP” uppermost.
12Fit the upper compression ring, and offset
the ring gap by 180°to the lower compression
ring gap. If a stepped ring is being fitted, fit
the ring with the smaller diameter of the step
uppermost.
13If new pistons are to be fitted, they must
be selected from the grades available, after
measuring the cylinder bores as described in
Section 36.
14Normally the appropriate oversize pistons
are supplied by the dealer when the block is
rebored.15Whenever new piston rings are being
installed, the glaze on the original cylinder
bores should be “broken”, using either
abrasive paper or a glaze-removing tool in an
electric drill. If abrasive paper is used, use
strokes at 60°to the bore centre line, to create
a cross-hatching effect.
34Crankshaft and bearings -
removal and refitting
4
Note: New main bearing cap bolts must be
used on refitting
Removal
1With the engine removed from the vehicle,
continue as follows.
2Remove the cylinder head, as described
previously in Section 20.
3Remove the sump, oil pick-up pipe and
sump baffle (where applicable), as described
in Section 29.
4Remove the oil pump, as described in
Section 30.
5Remove the flywheel or flexplate (if
applicable), as described in Sections 25 and
26.
6Remove the pistons and connecting rods,
as described in Section 32.
7Invert the engine so that it is standing on
the top face of the cylinder block.
8The main bearing caps are numbered 1 to 4
from the timing belt end of the engine. The
rear (flywheel end) cap is not marked. Toensure that the caps are refitted the correct
way round, note that the numbers are read
from the coolant pump side of the engine with
the engine inverted (see illustration).
9Unscrew and remove the main bearing cap
bolts, and tap off the bearing caps. If the
bearing shells are to be re-used, tape them to
their respective caps.
10Note that the centre bearing shell
incorporates thrust flanges to control
crankshaft endfloat.
11Lift the crankshaft (complete with timing
sensor wheel, if fitted), from the crankcase.
12Extract the upper bearing shells, and
identify them for position if they are to be
re-used.
13The crankshaft, bearings and sensor
wheel can be examined for wear and damage,
as described in Section 35, and the cylinder
block and bores can be examined as
described in Section 36.
Refitting
14Begin refitting by ensuring that the
crankcase and crankshaft are thoroughly
clean, and that all oilways are clear. If
possible, blow through the oil drillings with
compressed air, and inject clean engine oil
into them.
15If the crankshaft is being replaced, where
applicable, transfer the timing sensor wheel
and tighten to correct torque.
16Wipe clean the bearing shell seats in the
crankcase and the bearing caps, then fit the
upper bearing shells to their seats.
17Note that there is a tag on the back of
each bearing shell, which engages with a
groove in the relevant seat in the crankcase or
bearing cap (see illustration).
18If new bearing shells are being fitted, wipe
away all traces of protective grease.
SOHC engine procedures 2A•31
33.6 Measuring a piston ring end gap
using a feeler blade34.8 Main bearing cap identification mark
(arrowed) - 1.6 litre engine34.17 Main bearing shell tag (arrowed)
engages with groove in cylinder block -
2.0 litre SOHC engine
33.5C Sectional view showing correct
orientation of piston rings - all engines33.5B Removing the centre section of the
oil control ring - 2.0 litre SOHC engine
2A
A good alternative to
compressed air, is to use a
water dispersing lubricant
spray into each hole, using
the spout provided.
Page 229 of 525

19Note that the central bearing shells have
thrust flanges which control crankshaft
endfloat (see illustration). Note also that the
shells fitted to the crankcase all have oil duct
holes, while only the centre main bearing cap
shell has an oil duct hole.
20When the shells are firmly located in the
crankcase and the bearing caps, lubricate
them with clean engine oil.
21Fill the lips of a new crankshaft rear oil
seal with grease, and fit it to the end of the
crankshaft.
22Carefully lower the crankshaft into
position in the crankcase (see illustration).
23If necessary, seat the crankshaft using
light blows with a rubber hammer on the
crankshaft balance webs.
24Lubricate the main bearing journals and
shells (see illustration), and then fit numbers
2, 3 and 4 main bearing caps, and tighten the
new bolts as far as possible by hand.25Fill the side grooves of the rear main
bearing cap with RTV jointing compound
(Vauxhall part No 90485251, or equivalent).
Coat the lower surfaces of the bearing cap
with sealing compound (Vauxhall part No 15
04 200, or equivalent), (see illustrations). Fit
the bearing cap, and tighten the new bolts as
far as possible by hand.
26Fit the front (No 1) main bearing cap, and
tighten the new bolts as far as possible by
hand, ensuring that the bearing cap is exactly
flush with the end face of the cylinder block.
27Working from the centre bearing cap
outwards, tighten the bearing cap securing
bolts to the specified torque in the two stages
given in the Specifications; i.e. tighten all bolts
to Stage 1, then tighten all bolts to Stage 2
and Stage 3 (see illustrations).28When all bolts have been fully tightened,
inject further RTV jointing compound into the
side grooves of the rear main bearing cap,
until it is certain that they are full.
29Now rotate the crankshaft, and check that
it turns freely, with no signs of binding or tight
spots.
30Check that the crankshaft endfloat is
within the specified limits, using a dial gauge,
or by inserting a feeler blade between the
thrust flange of the centre main bearing shell
and the machined surface of the crankshaft
(see illustrations). Before measuring, ensure
that the crankshaft is fully forced towards one
end of the crankcase, to give the widest
possible gap at the measuring location.
Incorrect endfloat will most likely be due to
crankshaft wear or to incorrect regrinding,
assuming that the correct bearing shells have
been fitted.
2A•32SOHC engine procedures
34.19 Fitting a central main bearing shell.
Note thrust flanges -
2.0 litre SOHC engine34.24 Lubricate the main bearing shells
before fitting the caps -
2.0 litre SOHC engine
34.30B . . .or a feeler blade -
2.0 litre SOHC engine
34.27A Tighten the main bearing cap bolts
to the specified torque . . .
34.27B . . .then through the specified
angle - 2.0 litre SOHC engine34.30A Check crankshaft endfloat using a
dial gauge . . .
34.25B . . .and the lower surfaces with
sealing compound -
2.0 litre SOHC engine34.25A Fill the side grooves of the rear
main bearing cap with RTV jointing
compound . . .
34.22 Lowering the crankshaft into the
crankcase -
2.0 litre SOHC engine
Page 230 of 525

31Refit the previously removed
components, referring to the relevant
Sections of this Chapter.
35Crankshaft and bearings -
examination
4
Examination
1Examine the crankpin and main journal
surfaces for signs of scoring or scratches, and
check the ovality and taper of the crankpins
and main journals. If the bearing surface
dimensions do not fall within the tolerance
ranges given in the Specifications at the
beginning of this Chapter, the crankpins
and/or main journals will have to be reground.
2Big-end and crankpin wear is accompanied
by distinct metallic knocking, particularly
noticeable when the engine is pulling from low
revs, and some loss of oil pressure.
3Main bearing and main journal wear is
accompanied by severe engine vibration rumble
- getting progressively worse as engine rev’s
increase - and again by loss of oil pressure.
4If the crankshaft requires regrinding, take it
to an engine reconditioning specialist, who
will machine it for you and supply the correct
undersize bearing shells.
5Inspect the big-end and main bearing shells
for signs of general wear, scoring, pitting and
scratches. The bearings should be matt grey
in colour. With leadindium bearings, should a
trace of copper colour be noticed, the
bearings are badly worn, as the lead bearing
material has worn away to expose the indium
underlay. Renew the bearings if they are in
this condition, or if there are any signs of
scoring or pitting. You are strongly advised
to renew the bearings - regardless of their
condition at time of major overhaul.
Refitting used bearings is a false economy.
6The undersizes available are designed to
correspond with crankshaft regrind sizes. Thebearings are in fact, slightly more than the
stated undersize, as running clearances have
been allowed for during their manufacture.
7Main and big-end bearing shells can be
identified as to size by the marking on the
back of the shell. Standard size shell bearings
are marked STD or .00, undersize shells are
marked with the undersize such as 0.020 u/s.
This marking method applies only to
replacement bearing shells, and not to those
used during production.
8An accurate method of determining bearing
wear is by using a Plastigage. The crankshaft
is located in the main bearings (and, if
necessary, the big-end bearings), and the
Plastigage filament is located across the
journal. Vauxhall recommend that the
crankshaft journal and bearing shells are
lightly lubricated, to prevent the Plastigage
from tearing as the bearing cap is removed.
The bearing cap should be fitted, and the
bolts tightened to the specified torque. The
cap is then removed, and the width of the
filament is checked against a scale that shows
the bearing running clearance. The clearance
should be compared with that given in the
Specifications.
9Where applicable, check the teeth of the
crankshaft TDC sensor wheel for damage
(see illustration). If evident, the crankshaft
must be renewed.
10Similarly, check the condition of the pins
in the front crankshaft balance weight, which
serve as detect points for the plug-in
diagnostic sensor used by Vauxhall dealers
(see illustration).
36Cylinder block and bores -
examination and renovation
4
Examination
1Examine the cylinder bores for taper,
ovality, scoring and scratches. Start bycarefully examining the top of the cylinder
bores. If they are at all worn, a very slight
ridge will be found on the thrust side. This
marks the top of the piston ring travel. The
owner will have a good indication of the bore
wear before dismantling the engine, or
removing the cylinder head. Excessive oil
consumption, accompanied by blue smoke
from the exhaust, is a sure sign of worn
cylinder bores and piston rings.
2Measure the bore diameter across the
block, and just below any ridge. This can be
done with an internal micrometer or a dial
gauge. Compare this with the diameter of the
bottom of the bore, which is not subject to
wear. If no measuring instruments are
available, use a piston from which the rings
have been removed, and measure the gap
between it and the cylinder wall with a feeler
blade. Refer to the Specifications. If the
cylinder wear exceeds the permitted
tolerances, then the cylinders will need
reboring, in which case note the following
points:
a)Piston and cylinder bores are closely
matched in production. The actual
diameter of the piston is indicated by
numbers on its crown; the same numbers
stamped on the crankcase indicate the
bore diameter
b)After reboring has taken place, the
cylinder bores should be measured
accurately and oversize pistons selected
from the grades available to give the
specified piston-to-bore clearance
c)For grading purposes, the piston diameter
is measured across the bottom of the skirt
3If the wear is marginal and within the
tolerances given, new special piston rings can
be fitted to offset the wear.
4Thoroughly examine the crankcase and
cylinder block for cracks and damage, and
use a piece of wire to probe all oilways and
waterways to ensure that they are
unobstructed.
SOHC engine procedures 2A•33
35.10 Check the condition of the pins (arrowed) in the front
crankshaft balance weight - 2.0 litre SOHC engine35.9 Check the condition of the TDC sensor wheel teeth at the
front of the crankshaft - 2.0 litre SOHC engine
2A