check engine OPEL VECTRA 1988 Service Manual PDF

Apply a little grease to the threads of the
securing bolt, and tighten it to the specified
torque in the two stages given in the Specifi-
cations. Ensure that the thrustwasher is in
place under the bolt head, and prevent the
crankshaft from turning as during removal.
23Refit the camshaft sprockets. Ensure that
the locating pins on the ends of the camshafts
engage with the holes in the sprockets and
with the sprocket timing marks facing
forwards. Then tighten the securing bolts to
the specified torque in the two stages given in
the Specifications. Prevent the camshafts
from turning as during removal.
24Check the condition of the camshaft
cover rubber gasket and renew if necessary,
then refit the camshaft cover and tighten the
securing bolts (see illustration).
25Refit the HT leads to the spark plugs
(ensuring that they are refitted to their correct
cylinders), then clip the leads to the end of the
camshaft cover. Refit the spark plug cover
and tighten the securing bolts.
26Reconnect the breather hose to the
camshaft cover.
27Temporarily refit the crankshaft pulley,
and ensure that the crankshaft pulley and
camshaft sprocket timing marks are still
aligned as described in paragraph 6. Then fit a
new timing belt around the sprockets and
pulleys, starting at the crankshaft sprocket.
28Refit the crankshaft pulley, and tighten the
securing bolts to the specified torque. If
necessary, prevent the crankshaft from
turning as during removal. 29Adjust the timing belt tension, as
described from paragraph 35 onwards.
30Refit the outer timing belt cover, ensuring
that the rubber grommets are in place in the
screw holes, and tighten the securing screws.
31Refit the alternator drivebelt and adjust
the drivebelt tension, as described in Chapter
5.
32Refit the power steering pump drivebelt
and adjust the drivebelt tension, as described
in Chapter 10.
33Refit the air cleaner components as
applicable, referring to Chapter 4B, if
necessary.
34Reconnect the battery negative lead.
Adjustment
Note: The manufacturers specify the use of
special adjustment wrench Vauxhall tool No
KM-666 for adjusting the timing belt tension. If
access to this tool cannot be obtained an
approximate adjustment can be achieved
using the method described in this Section.
However it is emphasised that the vehicle
should be taken to a dealer at the earliest
possible opportunity to have the tension
adjusted using the special tool. Do not drive
the vehicle over any long distance until the
belt tension has been adjusted by a dealer
Approximate adjustment
35No checking of timing belt adjustment is
specified, and the following adjustment
procedure applies to a newly fitted belt. The
adjustment must be carried out with the
engine cold.36With the timing belt cover removed and
the tensioner pulley bolt slackened, ensure
that the TDC marks on the camshaft
sprockets and the crankshaft pulley are
aligned as described in paragraph 6. If
necessary, turn the crankshaft to achieve
alignment.
37Have an assistant press the tensioner
pulley against the belt until the belt can just be
twisted through 45°, using moderate pressure
with the thumb and forefinger, on the longest
belt run between the exhaust camshaft
sprocket and the belt idler pulley.
38Have the assistant hold the tensioner
pulley in position, and tighten the tensioner
pulley bolt to the specified torque in the two
stages given in the Specifications.
39Turn the crankshaft clockwise through
two complete revolutions, and check that,
with the crankshaft pulley TDC mark aligned
with the pointer on the rear timing belt cover,
the TDC marks on the camshaft sprockets are
still aligned with the notches in the camshaft
cover.
40Proceed as described in paragraphs 30 to
34, inclusive.
41Have the belt tension adjusted by a
Vauxhall dealer using the manufacturer’s
special tool at the earliest opportunity.Adjustment using Vauxhall special
tool (KM-666)
42Proceed as described in paragraphs 35
and 36.
43Fit the special tool KM-666 to the belt
tensioner pulley mounting plate, in
accordance with the tool manufacturer’s
instructions.
44Working anti-clockwise from the TDC
mark on the exhaust camshaft sprocket, mark
the seventh tooth on the sprocket (see
illustration).
45Turn the crankshaft clockwise until this
tooth is aligned with the TDC notch in the
camshaft cover. The crankshaft must be
turned evenly and without jerking, to prevent
the timing belt from jumping off the sprockets
and pulleys.
46Tighten the tensioner pulley bolt to the
specified torque in the two stages given in the
Specifications.
47Remove the special tool.
DOHC engine procedures 2B•5
4.21 Belt tensioner pulley and spacer
sleeve. Note that smaller diameter of
spacer sleeve fits against pulley
4.44 Working anti-clockwise from the TDC
mark on the exhaust camshaft sprocket,
mark the seventh tooth on the sprocket4.24 Tightening a camshaft cover securing
bolt
4.19B Rear timing belt cover lower right-
hand securing bolt4.19A Timing belt outer cover screw upper
stud (1) and rear belt cover upper
securing bolts (2)
2B

48Turn the crankshaft clockwise until the
TDC marks on the camshaft sprockets are
aligned with the notches in the camshaft
cover, and check that the crankshaft pulley
TDC mark is aligned with the pointer on the
rear timing belt cover.
49Proceed as described in paragraphs 30 to
34 inclusive.
5Timing belt, with automatic
adjuster- removal, refitting
and adjustment
3
Removal
1The operations are essentially the same as
described in Section 4, except that the
tensioner pulley incorporates an automatic
adjuster that simplifies the procedure as
follows.
2To release the belt tension before removal,
unscrew the timing belt tensioner pulley
securing bolt slightly then, with a large
screwdriver (or similar tool) inserted in the slot
on the tensioner arm, turn the tensioner arm
until the timing belt is slack. Tighten the
securing bolt slightly to hold the tensioner in
this position.
Refitting
3To refit the timing belt, first ensure that the
coolant pump is correctly positioned by
checking that the lug on the coolant pump
flange is aligned with the corresponding lug
on the cylinder block. If this is not the case,
slacken the coolant pump mounting bolts
slightly and move the pump accordingly.
Tighten the bolts to the specified torque on
completion (see Chapter 3).
4Refit the timing belt as described in Section 4,
then tension it as follows.
Adjustment
5Slacken the tensioner pulley securing bolt
and move the tensioner arm anti-clockwise,
until the tensioner pointer lies at its stop.
Tighten the tensioner pulley securing bolt to
hold the tensioner in this position.
6Turn the crankshaft through two complete
revolutions in the normal direction of rotation
and check that with the crankshaft pulley TDC
mark aligned with the pointer on the rear
timing belt cover, the TDC marks on the
camshaft sprockets are still aligned with the
notches in the camshaft cover.
7Slacken the tensioner pulley securing bolt
once again and move the tensioner arm
clockwise, until the tensioner pointer is
aligned with the notch in the tensioner. In the
first few hours of operation a new belt will be
subjected to ‘settling-in’, (known as the
running-in procedure). If you are refitting a
used belt (one that has been ‘run-in’), align the
pointer to approximately 4 mm to the left of
the notch, refer to Section 14 in Chapter 2A.
Tighten the tensioner pulley securing bolt
securely. Turn the crankshaft through onecomplete revolution in the normal direction of
rotation and check that the crankshaft and
camshaft timing marks still align, then refit the
remainder of the components as described in
Section 4.
8With the timing belt adjustment set in this
way, correct tension will always be maintained
by the automatic tensioner and no further
checking or adjustment will be necessary.
6Camshaft front oil seal-
removal and refitting
3
Note: A new timing belt should be used on
refitting
Removal
1The camshaft front oil seals may be
renewed with the engine in the vehicle without
removing the camshafts as follows.
2Remove the timing belt and the relevant
camshaft sprocket(s), as described in Section 4.
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.
4Clean the oil seal seat with a wooden or
plastic scraper.
5Turn the camshaft until the locating peg for
the camshaft sprocket is uppermost, then
lubricate the lips of a new camshaft front oil
seal with a little grease, and fit the oil seal,
using a tube or socket of similar diameter with
a washer and the camshaft sprocket bolt.Screw the camshaft sprocket bolt into the end
of the camshaft to draw the oil seal into
position on its shoulder (see illustration).
6Where applicable, repeat the procedure on
the remaining camshaft oil seal.
Refitting
7Refit the camshaft sprockets, the timing
belt and tension the timing belt as described
in Sections 4 and 5.
7Camshafts- removal,
inspection and refitting
4
Note: A new timing belt should be used on
refitting
Removal
1Remove the timing belt and the relevant
camshaft sprockets, as described in Section 4.
2If the exhaust camshaft is to be removed,
unscrew the two securing bolts and remove
the distributor from the end of the cylinder
head, referring to Chapter 5, if necessary.
3Check the camshaft bearing caps for identi-
fication marks, and if none are present, make
corresponding marks on the bearing caps and
the top surface of the cylinder head using a
centre punch. Note the orientation of the
bearing caps before removal, as they must be
refitted in exactly the same positions from
which they are removed (see illustration).
4Loosen the relevant camshaft bearing cap
nuts by half a turn, then loosen all the nuts by
a further half turn and so on (this is necessary
to slowly relieve the tension in the valve
springs). Note that the exhaust camshaft rear
bearing cap that also supports the distributor
is secured by four nuts (see illustration).
5Remove the bearing cap nuts and the
bearing caps, then carefully lift the relevant
camshaft from the cylinder head without
jerking.
6Repeat the procedure for the remaining
camshaft if desired.
Inspection
7With the camshaft(s) removed, examine the
bearing surfaces in the cylinder head and
bearing caps for signs of obvious wear or
2B•6DOHC engine procedures
6.5 Using the camshaft sprocket bolt,
washer, and a tube to fit a new camshaft
front oil seal
7.4 Exhaust camshaft rear bearing cap
securing nuts (arrowed)7.3 Camshaft bearing cap. Note position
of identification mark (arrowed)

pitting. If evident, the cylinder head and all
bearing caps must be renewed as a matched
set, as there is no provision for refacing if the
bearing caps cannot be renewed individually.
8The camshaft(s) should show no marks or
scoring on the journal or cam lobe surfaces. if
evident, renew the camshaft(s).
9It is advisable to renew the camshaft front
oil seal(s) as a matter of course. Prise the old
seal(s) from the front of the camshaft(s) and
discard them.
Refitting
10Begin refitting by liberally coating the
contact faces of the hydraulic valve lifters and
the camshaft(s) with molybdenum disulphide
paste.
11Coat the mating faces of the front and
rear bearing caps with sealing compound and
refit the bearing caps in their original positions
as noted during removal.
12Tighten the camshaft bearing cap nuts to
the specified torque in half-turn stages, as
when loosening the nuts. Note that when
refitting the exhaust camshaft, the two smaller
rear bearing cap securing nuts should be
tightened after all the main camshaft bearing
cap nuts have been tightened. Note also that
the two smaller nuts should be tightened to a
lower torque wrench setting than the main
nuts.
13Turn the camshaft until the locating peg
for the camshaft sprocket is uppermost, then
lubricate the lips of a rear camshaft front oil
seal with a little grease, and fit the oil seal,
using a tube or socket of similar diameter with
a washer and the camshaft sprocket bolt.
Screw the camshaft sprocket bolt into the end
of the camshaft to draw the oil seal into
position on its shoulder.
14Repeat the procedure for the remaining
camshaft.
15Refit the distributor with reference to
Chapter 5. Fit a new timing belt and the
camshaft sprockets, then adjust the timing
belt as described in Section 4 or 5, as
applicable.
8Cylinder head -removal and
refitting (engine in vehicle)
4
Note: The engine must be cold when the
cylinder head is removed. Do not remove the
cylinder head from a hot engine. New cylinder
head bolts, a new cylinder head gasket and a
new timing belt must be used on refitting.
The torque settings (as shown in Chapter 2A)
are only applicable to latest specification head
bolts, available from Vauxhall. Earlier type or
alternative make, head bolts may require
different torques. Consult your supplier
Removal
1Disconnect the battery negative lead.
2Drain the cooling system, as described in
Chapter 3.3Remove the front section of the exhaust
system, as described in Chapter 4C.
4The cylinder head can be removed
complete with the inlet manifold, or the inlet
manifold can be detached from the cylinder
head before removal, with reference to
Chapter 4B. If no work is to be carried out on
the inlet manifold, it can be unbolted from the
cylinder head and supported to one side out
of the way, thus avoiding the need to
disconnect the relevant hoses, pipes and
wiring.
5If the cylinder head is to be removed
complete with the inlet manifold, disconnect
all relevant hoses, pipes and wiring from the
inlet manifold and associated components,
referring to Chapter 4B, and unbolt the
manifold support bracket from the manifold.
Loosen the alternator mountings with
reference to Chapter 5, then unbolt the upper
alternator mounting from the inlet manifold.
6If the inlet manifold is to be left in the engine
compartment, continue as follows, otherwise
go on to paragraph 17.
7Disconnect the wiring plug from the airflow
meter, and the breather hose from the air box
on the throttle body. Disconnect the air
cleaner trunking and remove the airflow
meter/air box assembly from the throttle
body. Refer to Chapter 4B if necessary.
8Disconnect the end of the throttle cable
from the throttle valve lever, then unbolt the
throttle cable support bracket and remove it
from the inlet manifold.
9Unscrew the two earth lead securing nuts
from the fuel rail (one at each end of the rail)
and disconnect the three earth leads.
10Disconnect the wiring plug from the
throttle position switch.
11Pull up on the wiring harness housing, and
disconnect the wiring plugs from the fuel
injectors by compressing the retaining clips.
Move the wiring harness housing to one side.
12Disconnect the two breather hoses from
the rear of the camshaft cover.
13Loosen the alternator mountings, with
reference to Chapter 5, then unbolt the upper
alternator mounting from the inlet manifold.
14Unbolt the manifold support bracket from
the manifold.15Make a final check to ensure that all
necessary hoses, pipes and wires have been
disconnected, then unscrew the securing nuts
and lift the inlet manifold from the cylinder
head. Ensure that the manifold is properly
supported, taking care not to strain any of the
hoses, pipes and wires, etc., which are still
connected.
16Recover the manifold gasket from the
cylinder head.
17Remove the timing belt, camshaft
sprockets, and timing belt tensioner and idler
pulleys, as described in Section 4.
18Unscrew the upper and middle studs for
the timing belt outer cover screws. Note that
the upper stud simply unscrews from the
cylinder head, but the middle stud is secured
by a bolt.
19Unscrew the two upper rear timing belt
cover securing bolts from the cylinder head.
20Remove the distributor cap and HT leads
with reference to Chapter 5.
21Disconnect the distributor wiring plug.
22Disconnect the coolant hose from the
left-hand end of the cylinder head.
23Unscrew the bolt securing the crankcase
breather tube bracket to the end of the
cylinder head.
24Disconnect the radiator top hose from the
thermostat housing, and disconnect the
wiring plugs from the temperature gauge
sender and the coolant temperature sensor
(both situated in the thermostat housing).
25Make a final check to ensure that all
relevant hoses, pipes and wires have been
disconnected.
26On X20 XEV models, remove the
camshaft, as described in Section 7.
27Using a Torx socket, and working in the
order shown (see illustrations), loosen all the
cylinder head bolts by a quarter of a turn, then
loosen all the bolts by half a turn, and finally
loosen and remove the bolts. Recover the
washers. Note that the loosening sequence
on X20 XEV differs to other DOHC engines.
28Lift the cylinder head from the cylinder
block. If necessary, tap the cylinder head
gently with a soft-faced mallet to free it from
the block, but do not lever at the mating
faces. Note that the cylinder head is located
on dowels.
DOHC engine procedures 2B•7
8.27B Cylinder head bolt loosening
sequence - (X 20 XEV engines)8.27A Cylinder head bolt loosening
sequence - (20 XEJ and C 20 XE engines)
2B

29Recover the cylinder head gasket and
discard it.
30Clean the cylinder head and block mating
faces by careful scraping. Take care not to
damage the cylinder head, which is made of
light alloy and is easily scored. Cover the
coolant passages and other openings with
masking tape or rag, to prevent dirt and
carbon falling in. Mop out all the oil from the
bolt holes; if oil is left in the holes, hydraulic
pressure could crack the block when the bolts
are refitted.
31If desired, the cylinder head can be
dismantled and inspected as described in
Section 10.
Refitting
32Begin refitting by locating a new gasket
on the block so that the word “OBEN” or
“TOP” is uppermost at the timing belt end of
the engine.
33With the mating faces scrupulously clean,
locate the cylinder head on the block so that
the positioning dowels engage in their holes.
34Temporarily refit the crankshaft pulley and
the camshaft sprockets, and ensure that the
timing marks are still positioned as they were
before the timing belt was removed (see
Section 4).35Fit the new cylinder head bolts, ensuring
that the washers are in place under their
heads, and screw the bolts in by hand as far
as possible.
36Tighten the bolts in the order shown (see
illustrations). Note that the tightening
sequence on X20 XEV differs to other DOHC
engines. Tighten the bolts in the four stages
given in the Specification (see Chapter 2A, as
2.0 litre) - i.e. tighten all bolts to the Stage 1
torque, then tighten all bolts to Stage 2 and so
on (see illustrations).
37Further refitting is a reversal of the
removal procedure, remembering the
following points.
38Refit the timing belt tensioner and idler
pulleys, camshaft sprockets and a new timing
belt as described in Section 4, and tension the
timing belt as described in Sections 4 and 5.
39Where applicable, refit the inlet manifold
to the cylinder head with reference to Chapter
4B, using a new gasket.
40Refit the front section of the exhaust
system as described in Chapter 4C, using a
new gasket.
41Refit the upper alternator mounting to the
inlet manifold (where applicable), then adjust
the alternator drivebelt tension, as described
in Chapter 5.
42Refill the cooling system, (Chapter 3).43On completion, check that all relevant
hoses, pipes and wires, etc., have been
reconnected.
44When the engine is started, check for
signs of leaks.
45Once the engine has reached normal
operating temperature, check and if
necessary adjust the mixture (where
applicable) with reference to Chapter 4B.
9Cylinder head -removal and
refitting (engine removed)
4
Note: New cylinder head bolts, a new cylinder
head gasket, and a new timing belt must be
used on refitting.
The torque settings (as shown in Chapter 2A)
are only applicable to latest specification head
bolts, available from Vauxhall. Earlier type or
alternative make, head bolts may require
different torques. Consult your supplier.
Removal
1The cylinder head can be removed
complete with the inlet manifold, or the inlet
manifold can be detached from the cylinder
head before removal, with reference to
Chapter 4B.
2Proceed as described in Section 8,
paragraphs 17 to 19 inclusive.
3If not already done, remove the distributor
cap and HT leads, referring to Chapter 5.
2B•8DOHC engine procedures
8.36A Cylinder head bolt tightening sequence -
20 XEJ and C 20 XE engines
8.36C Tighten the cylinder head bolts to
the specified torque . . .8.36D . . .and then through the specified
angle
8.36B Cylinder head bolt tightening sequence -
X 20 XEV engines
Warning: The exhaust valves
fitted to 20 XEJ and C 20 XE
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.

4Unscrew the bolt securing the crankcase
breather tube bracket to the end of the
cylinder head.
5Make a final check to ensure that all
relevant hoses, pipes and wires have been
disconnected.
6Continue as described in Section 8,
paragraphs 26 to 31.
Refitting
7Proceed as described in Section 8,
paragraphs 32 to 38 inclusive but in addition
note the following.
8On completion, check that all relevant
hoses, pipes and wires, etc., have been
reconnected.
10Cylinder head- dismantling
and reassembly
4
Dismantling
1With the cylinder head removed as
described in Section 8, clean away all external
dirt.
2If not already done, remove the thermostat
housing and thermostat as described in
Chapter 3, and remove the manifolds as
described in Chapters 4B and 4C.
3Remove the spark plugs (if not already
done), and remove the distributor with
reference to Chapter 5.
4Remove the camshafts as described in
Section 7.
5Remove the hydraulic valve lifters from their
bores using a rubber suction plunger tool - do
not invert the cylinder head to remove the
valve lifters. Keep the valve lifters upright at all
times (oil groove at bottom (see illustration)),
and immerse them in order of removal in a
container of clean engine oil until they are to
be refitted.
6To remove the valve components, continue
as described in Chapter 2A, Section 22,paragraphs 3 to 7 inclusive.
7The cylinder head and valves can be
inspected for wear and damage as described
in Chapter 2A, Section 23.
Reassembly
8With all components cleaned, refit the valve
components as described in Chapter 2A,
Section 22, paragraphs 10 to 19 inclusive.
9Refit the hydraulic valve lifters to the
cylinder head in their original positions.
Liberally oil the valve lifter bores, and if new
lifters are being fitted, initially immerse each
one in a container of clean engine oil and
compress it (by hand) several times to charge
it.
10Refit the camshafts, as described in
Section 7.
11Refit the spark plugs if desired, and refit
the distributor with reference to Chapter 5.
12Where applicable, refit the manifolds
and/or the thermostat and housing.
13Refit the cylinder head, as described in
Sections 8 and 9, as applicable.
11Valve lifters- general
Although the valve lifters on these engines
cannot be dismantled they should be carefully
inspected for obvious signs of wear on the
contact faces. Also check the valve lifter oil
holes for obstructions and for any signs of oil
sludge build-up. If excessive wear is evident
(this is unlikely), all the valve lifters must be
renewed as a set.
12Crankshaft front oil seal -
renewal
3
1The procedure is similar to SOHC models(see Chapter 2A), noting the following points.
2The spacer ring (if fitted), from the end of
the crankshaft, must be removed, before
refitting.
3After fitting the new seal, coat the oil pump
mating face of the spacer ring with sealing
compound, then push the spacer ring onto
the end of the crankshaft, until it is seated
against the oil pump.
4The timing belt should be renewed.
5Refit the rear timing belt cover and the
timing belt, as described in Section 4. Adjust it
as described in Section 4 and 5.
13Sump - removal and refitting
3
Note: Sump gaskets, cannot be reused.
Ensure that new gaskets are obtained before
removing the sump
Removal
1The procedure is similar to SOHC models
(see Chapter 2A), with the following variations.
2The engine undershield must be removed.
3Remove both the cork gaskets and clean all
sealing surfaces, scrupulously.
Refitting
4Locate a new gasket on the cylinder block,
if necessary applying a little sealing
compound to hold it in place.
5Locate the remaining new gasket on the
sump baffle, but do not use sealing
compound.
14Oil pump - removal and
refitting
3
Removal
1Apart from the following variations, the
procedure is the same as for SOHC models.
2If the engine is still in the vehicle,
disconnect the oil cooler pipe unions from the
oil pump, and move the pipes to one side out
DOHC engine procedures 2B•9
14.2 Oil cooler pipe unions at oil pump
10.5 Remove the hydraulic valve lifters using a rubber plunger. Inset (A) shows valve
lifter upright, with oil groove (arrowed) at bottom
2B

of the way (see illustration).
3Remove the spacer ring from the end of the
crankshaft (see illustration).
Refitting
4Coat the oil pump mating face of the spacer
ring with sealing compound, then push the
spacer ring onto the end of the crankshaft
until it is seated against the oil pump.
5The timing belt should be renewed, see
Sections 4 and 5, for details.
6Remember also to reconnect the oil cooler
pipes to the oil pump, and tighten the unions.
15Oil cooler - removal and
refitting
3
Removal
1To gain sufficient access to remove the oil
cooler, the radiator must be removed (as
described in Chapter 3). Alternatively, the
front bumper can be removed, as described in
Chapter 11 (see illustration).
2With the appropriate component(s)removed for access, unscrew the oil cooler
pipe unions from the oil cooler. Be prepared
for oil spillage, and plug the open ends of the
pipes, to prevent further oil leakage and dirt
ingress.
3Unscrew the two securing nuts, and
withdraw the oil cooler from its mounting
brackets.
Refitting
4Refitting is a reversal of removal, but on
completion, check and if necessary top-up
the engine oil level, as described in Chapter 1.
2B•10DOHC engine procedures
15.1 Oil cooler viewed through front spoiler. Securing nuts
arrowed14.3 Oil pump securing bolts (arrowed) and crankshaft spacer
ring (A)

18 SV, C18 NZ, 20 NE, C20 NE and 20 SEH:
New belt, cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.5
New belt, warm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.5
Used belt, cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.5
Used belt, warm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.0
Valves and guidesInletExhaust
Overall length - production (mm):
14 NV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105.0105.0
16 SV, X 16 SZ and C16 NZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101.5101.5
C16 NZ2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104.2104.2
18 SV, C18 NZ, 20 NE, C20 NE and 20 SEH . . . . . . . . . . . . . . . . . . .104.2104.0
Overall length - service (mm):
14 NV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104.6104.6
16 SV, X 16 SZ and C16 NZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101.1101.1
C16 NZ2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103.8103.8
18 SV, C18 NZ, 20 NE, C20 NE and 20 SEH . . . . . . . . . . . . . . . . . . .103.8103.6
Head diameter (mm):
14 NV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.029.0
16 SV, X 16 SZ, C16 NZ and C16 NZ2 . . . . . . . . . . . . . . . . . . . . . . . .38.031.0
18 SV, C18 NZ, 20 NE, C20 NE and 20 SEH . . . . . . . . . . . . . . . . . . .41.836.5
Stem diameter (mm), (all engines):
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.998 to 7.0126.978 to 6.992
0.075 mm oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.073 to 7.0877.053 to 7.067
0.150 mm oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.148 to 7.1627.128 to 7.142
0.250 mm oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.248 to 7.2627.228 to 7.242
Valve guide bore (mm), (all engines):
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.030 to 7.050
0.075 mm oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.105 to 7.125
0.150 mm oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.180 to 7.200
0.250 mm oversize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.280 to 7.300
Valve clearance in guide (mm), (all engines):
Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.018 to 0.052
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.038 to 0.072
Valve seat angle:
All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44º
Valve clearances:
All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Automatic adjustment by hydraulic lifters
Flywheel
Maximum permissible lateral run-out of starter ring gear (all models) . .0.5 mm
Refinishing limit -maximum depth of material that may be removed
from clutch friction surface (all models) . . . . . . . . . . . . . . . . . . . . . . .0.3 mm
Lubrication system
Lubricant type/specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Lubricants and fluids in “Weekly checks”
Lubricant capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Specifications
Oil pump clearances:
Inner-to-outer gear teeth clearance (backlash) (all models) . . . . . . . .0.0 to 0.2 mm
Gear-to-housing clearance (endfloat):
14 NV, 16 SV, C16 NZ and X 16 SZ . . . . . . . . . . . . . . . . . . . . . . . .0.08 to 0.15 mm
C16 NZ2, 18 SV, C18 NZ, 20 NE, C20 NE and 20 SEH . . . . . . . . .0.03 to 0.10 mm
Oil pressure at idle (engine warm) (all models) . . . . . . . . . . . . . . . . . . . .1.5 bar (21.8 lbf/in2
)
Torque wrench settingsNmlbf ft
Note:Use new bolts where asterisked (*). The torque settings stated for the cylinder head are only applicable to latest specification bolts, available
from Vauxhall. Earlier type or alternative make, head bolts may require different torques. Consult your supplier.
Air inlet pre-heat to exhaust manifold . . . . . . . . . . . . . . . . . . . . . . . . . .86
Alternator and inlet manifold to brackets:
1.4 and 1.6 litre, (except C16 NZ2) . . . . . . . . . . . . . . . . . . . . . . . . . . .2015
C16 NZ2, 1.8 and 2.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1813
Alternator to bracket (M8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3022
Alternator to bracket (M10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4030
Alternator to shackle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Big-end bearing cap: *
1.4 and 1.6 litre, (except C16 NZ2)
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Angle tighten by 30º
SOHC engine procedures 2A•5
2A

Oil pick-up pipe bracket to cylinder block . . . . . . . . . . . . . . . . . . . . . . .64
Oil pick-up pipe to oil pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Oil pipes to radiator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2216
Oil pressure switch to oil pump:
1.4 and 1.6 litre, (except C16 NZ2) . . . . . . . . . . . . . . . . . . . . . . . . . .3022
C16 NZ2, 1.8 and 2.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4030
Oil pressure relief valve to oil pump . . . . . . . . . . . . . . . . . . . . . . . . . . . .3022
Oil pump cover to oil pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Oil pump to cylinder block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Oxygen sensor to exhaust manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . .3022
Power steering pump bracket to support:
C16 NZ2, 1.8 and 2.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1813
Power steering pump to support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Right engine mounting to subframe . . . . . . . . . . . . . . . . . . . . . . . . . . . .6548
Shackle to alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Starter to cylinder block (M10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4533
Starter to cylinder block (M12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6044
Sump:
1.4 and 1.6 litre, (except C16 NZ2) . . . . . . . . . . . . . . . . . . . . . . . . . . .86
C16 NZ2, 1.8 and 2.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1511
Sump drain plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5541
Support to cylinder block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3526
Temperature sender to cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . .2015
Thermostat housing:
1.4 and 1.6 litre, (except C16 NZ2) . . . . . . . . . . . . . . . . . . . . . . . . . . .107
C16 NZ2, 1.8 and 2.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1511
Timing belt tensioner to oil pump:
1.4 and 1.6 litre, (except C16 NZ2) . . . . . . . . . . . . . . . . . . . . . . . . . . .5541
Timing belt cover to oil pump/camshaft housing:
1.4 and 1.6 litre, (except C16 NZ2) . . . . . . . . . . . . . . . . . . . . . . . . . . .129
C16 NZ2, 1.8 and 2.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Timing belt drive gear to crankshaft:
C16 NZ2, 1.8 and 2.0 litre:
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13096
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Angle tighten by between 40º to 50º
Transmission to engine (M10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4533
Transmission to engine (M12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6044
1General description
General
The engine is of four-cylinder, in-line single
or double overhead camshaft type (depending
on model), mounted transversely at the front
of the vehicle.
The crankshaft runs in five shell-type
bearings, and the centre bearing incorporates
a thrust bearing shell to control crankshaft
endfloat.
The connecting rods are attached to the
crankshaft by horizontally split shell-type
big-end bearings. On single overhead
camshaft (SOHC) models, the pistons are
attached to the connecting rods by gudgeon
pins, which are an interference fit in the
connecting rod small-end bore. The
aluminium alloy pistons are fitted with three
piston rings: two compression rings and an oil
control ring.
The camshaft on SOHC engines is driven
from the crankshaft by a toothed composite
rubber belt. Each cylinder has two valves (oneinlet and one exhaust), operated through
rocker arms that are supported at their pivot
ends by hydraulic self-adjusting valve lifters
(tappets).
The inlet and exhaust valves are each
closed by a single valve spring, and operate in
guides pressed into the cylinder head.
A gear-type oil pump is located in a housing
attached to the front of the cylinder block, and
is driven directly from the crankshaft. A
full-flow type oil filter is fitted.
The distributor is driven directly from the
end of the camshaft. On carburettor models,
the mechanical fuel pump is operated from
the front end of the camshaft. The coolant
pump is located at the front of the cylinder
block, and is driven by the timing belt.
Chapter 2A describes the SOHC engine
repair procedures. Many repairs and specifi-
cations to the DOHC engine are similar to the
2.0 litre SOHC. However where they differ,
details can be found in Chapter 2B.
Engine identification codes -
general
Before ordering spare parts, or carrying out
any repair or overhaul operations on the
engine, it is essential to identify the exactengine type being worked on. Later engines,
although outwardly similar in appearance,
often have significant differences in repair
procedures, even though they may be of the
same displacement and model year.
The following sub-Sections in this Chapter
are mainly specific to engine type, as will be
noted from the sub-Section headings. Check
the engine identification code first, which is
located on a horizontal surface on the exhaust
manifold side of the cylinder block, at the
distributor end. On later engines, the code is
on the cylinder block-to-transmission flange,
next to the engine oil dipstick.
2Crankcase ventilation
system - description and
maintenance
2
Description
1A crankcase ventilation system is fitted to
all models, but the systems differ in detail
depending on the model concerned.
2Oil fumes and blow-by gases (combustion
gases that have passed by the piston rings)
are drawn from the crankcase into the area of
SOHC engine procedures 2A•7
2A

12Disconnect the pressure sensor vacuum
pipe from the carburettor (see illustration).
13Remove the coolant hose(s) from the inlet
manifold and/or throttle body, as applicable.
14Disconnect the fuel hoses from the fuel
pump and vapour separator on carburettor
models or from the fuel pipes at the
right-hand side of the engine compartment on
other models. Be prepared for fuel spillage,
and take adequate fire precautions. Plug the
open ends of the pipes and hoses, to prevent
dirt ingress and further fuel leakage (see
illustrations).
15Disconnect all relevant wiring connections
and plugs, and remove the fuel injection
wiring harness. Pull up on the wiring harness
housing, and compress the wiring plug
retaining clips to release the harness housing
from the fuel injectors (see illustration).16Disconnect the heater coolant hoses from
the coolant gallery at the rear of the cylinder
block.
17Disconnect the wiring from the following
components (where applicable):
a)Starter motor
b)Distributor (note HT lead positions)
c)Oil pressure switch
d)Oil temperature switch
e)TDC sensor
f)Oil level sensor
g)Knock sensor
h)Coolant temperature sensor
i)Temperature gauge sender
18Make a final check to ensure that all
relevant hoses, pipes and wires have been
disconnected, and that they are positioned
clear of the engine.
19Remove the front section of the exhaust
system, as described in Chapter 4C.
20Unbolt and remove the bellhousing cover
plate (see illustration).
21Remove the clutch (if applicable), as
described in Chapter 6. On automatic models,
use chalk or a felt-tip pen to mark the
relationship of the torque converter to the
flexplate before unbolting the torque converter.
Refer to note at the beginning of this Section
and to Chapter 7B for further information.
22Remove the crankshaft pulley. Some
pulleys are secured by four bolts, which must
be unscrewed using an Allen key or hexagon
bit. Unscrew each of the three bolts in turn
and remove them. On other engines, the
pulley is secured by a single bolt, which alsosecures the crankshaft sprocket. On manual
transmission models, if the engine is in the
vehicle, the crankshaft can be prevented from
turning by having an assistant engage first
gear and depress the brake pedal.
Alternatively, the flywheel (or flexplate, on
automatics), ring gear teeth can be jammed,
through the bellhousing cover aperture using
a large screwdriver, or similar tool. Access to
the crankshaft pulley is most easily obtained
through the right-hand wheel arch, after
removing the roadwheel.
23Attach a hoist and lifting gear to the
engine lifting brackets on the cylinder head,
and support the weight of the engine.
24Unscrew and remove two of the three
upper engine-to-transmission bolts,
accessible from the engine compartment,
leaving one fastened for safety.
25Unbolt the right-hand engine mounting
from the body and from the cylinder block,
and withdraw the mounting bracket.
26Unscrew and remove the four lower
engine-to-transmission bolts.
27Support the transmission using a trolley
jack and interposed block of wood. Remove
the last upper transmission bolt.
28Manipulate the engine as necessary to
separate it from the transmission. Note that
the transmission locates on dowels in the
cylinder block.
29Carefully raise the hoist, and lift the
engine from the vehicle, taking care not to
damage any of the surrounding components
in the engine compartment.
SOHC engine procedures 2A•9
7.12 Disconnect the pressure sensor
vacuum pipe from the carburettor -
1.6 litre model
7.20 Removing the transmission
bellhousing cover plate7.15 Removing the fuel injection wiring
harness -
2.0 litre SOHC model7.14B Fuel hose-to-pipe connections at
right-hand side of engine compartment -
2.0 litre SOHC model
7.14A Disconnecting a fuel hose from the
fuel pump - 1.6 litre model
7.11B . . .and disconnect the choke
heater/pull-down solenoid wiring plug -
1.6 litre model7.11A Disconnect the coolant hoses from
the automatic choke housing . . .
2A

30With the engine removed, the
transmission can be supported by placing a
length of wood between the bellhousing and
the front suspension subframe. Once the
wooden support is in place, remove the trolley
jack from under the transmission.
Refitting
Note: New left and right-hand
engine/transmission mounting-to-body bolts
must be used on refitting.
31Use an M10 x 1.25 bottoming tap to clean
the threads in the torque converters threaded
bosses and ensure that new bolts are
available for reassembly, where applicable.
32Support the transmission with a trolley
jack and remove the length of wood from
between the bellhousing and the subframe.
33Support the engine with the hoist and
lifting tackle, and gently lower it into position
in the engine compartment.
34Mate the engine and transmission
together, ensuring that the transmission
locates on the dowels in the cylinder block,
then refit the three upper
engine-to-transmission bolts.
35Tighten all nuts and bolts to their specified
torque wrench settings. When tightening the
torque converter-to-flexplate bolts to their
specified torque wrench settings, a
commercially available adapter will be
required (see illustration).
36If the clutch is still bolted to the flywheel,
ensure that the weight of the transmission is
not allowed to hang on the input shaft as it is
engaged with the clutch friction disc.
37Refit the four lower
engine-to-transmission bolts, but again do not
fully tighten them at this stage.
38Fit the right-hand engine mounting
bracket to the cylinder block, and tighten the
securing bolts to the specified torque.39Manipulate the engine and transmission
as necessary to enable the right-hand engine
mounting-to-body bolts to be fitted, then fit
new bolts and tighten them to the specified
torque.
40Tighten all the engine-to-transmission
bolts to the specified torque, then disconnect
the lifting tackle and hoist from the engine,
and remove the trolley jack from beneath the
transmission.
41Refit the transmission bellhousing cover
plate.
42Refit the clutch, as described in Chapter
6.
43Refit the front section of the exhaust
system, as described in Chapter 4C.
44Refit the crankshaft pulley using a reversal
of the removal procedure described earlier in
paragraph 22, and tighten the securing bolt(s)
to the specified torque.
45Lower the vehicle to the ground.
46Refit all relevant wires, pipes and hoses,
etc., using a reversal of the removal
procedure described earlier.
47Where applicable, refit the power steering
pump, tension the pump drivebelt, and bleed
the hydraulic fluid circuit, as described in
Chapter 10.
48Refit the alternator and tension the
drivebelt, as described in Chapter 5.
49Refit the air cleaner components, referring
to Chapter 4A or 4B, if necessary. On
carburettor models reconnect the hot air hose
to the exhaust manifold hot air shroud.
50Fit a new oil filter (if not already replaced),
and fill the engine with oil, as described in
Chapter 1.
51Refit the radiator and refill the cooling
system, as described in Chapter 3.
52Refit the bonnet as described in Chapter
11.
53Reconnect the battery negative lead.
54Refer to Section 37
8Engine and transmission -
removal, separation,
reconnection and refitting
4
Note: A hoist and lifting tackle will be required
for this operation
Removal
1Proceed as described in Section 7,
paragraphs 1 to 18 inclusive.
2Working in the engine compartment,
remove the gear selector linkage, as
described in Chapters 7A and 7B, as
appropriate.
3On manual transmission models, remove
the retaining clip, then slide the clutch cable
from the release lever, pushing the release
lever back towards the bulkhead if necessary
to allow the cable to be disconnected. On
automatic models disconnect the selector
cable from the actuating lever, then either
unbolt the cable bracket or release the cable
from the bracket. In either case, pull the cablesupport from the bracket on the transmission
casing, then move the cable and secure to
one side out of the way, taking note of its
routing.
4Disconnect the wiring from the reversing
lamp switch, which is located at the front of
the manual transmission casing, above the
left-hand mounting bracket. On automatic
models, disconnect the transmission wiring
by unplugging the five connector plugs from
the various switches, solenoids and sensors.
Release also the wiring from any clips or ties
securing to the vehicle.
5Where applicable, withdraw the automatic
transmission breather hose from under the
battery bracket. Disconnect the oxygen
sensor wiring if fitted.
6Unscrew the securing sleeve, and
disconnect the speedometer cable from the
transmission.
7Unscrew the retaining nut, and disconnect
the earth strap from the transmission
endplate.
8Make a final check to ensure that all
relevant hoses, pipes, wires etc. have been
disconnected, and that they are positioned
clear of the engine and transmission.
9Proceed as described in Section 7,
paragraphs 19 and 22.
10Disconnect the inboard ends of the
driveshafts from the differential, referring to
the relevant paragraphs of Chapter 8. Be
prepared for oil spillage as the driveshafts are
withdrawn, and plug the apertures in the
differential, to prevent further loss of oil and
dirt ingress. Support the driveshafts by
suspending them with wire or string - do not
allow them to hang down under their own
weight.
11Attach a hoist and lifting gear to the
engine lifting brackets on the cylinder head,
and support the weight of the engine.
12Remove the left-hand transmission
mounting completely by unscrewing the two
bolts securing the rubber mounting to the
vehicle, body, and the three bolts securing the
mounting bracket to the transmission (see
illustration).
13Unbolt the right-hand engine mounting
from the body and from the cylinder block,
and withdraw the mounting bracket.
2A•10SOHC engine procedures
8.12 Left-hand transmission mounting
viewed from underside of vehicle7.35 Commercially-available torque
wrench adapter being used to tighten
torque converter bolts
If a tap is not available, cut
two slots into the threads of
one of the old flywheel bolts
and use the bolt to remove
the locking compound from the
threads.