Distributor
Direction of rotor arm rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Anti-clockwise (viewed from cap)
Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3-4-2 (No 1 cylinder at timing belt end of engine)
Dwell angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Automatically controlled by electronic module (not adjustable)
Ignition timing
14 NV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5°BTDC
16 SV, X 16 SZ, C 16 NZ, C 16 NZ2 and C 18 NZ . . . . . . . . . . . . . . . .10°BTDC *
18 SV and 2.0 litres models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 to 12°BTDC *
* Ignition timing electronically controlled no adjustment possible
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Specifications
Torque wrench settingNmlbf ft
Alternator mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Camshaft phase sensor disc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Camshaft phase sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1511
‘Compact’ series alternator lower mounting bolt . . . . . . . . . . . . . . . . . .3526
‘Compact’ series alternator upper mounting bolts . . . . . . . . . . . . . . . . .2015
DIS module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Inductive pulse pick-up to block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
Starter motor mounting bracket-to-cylinder block . . . . . . . . . . . . . . . . .2518
Starter motor mounting:
1.4 and 1.6 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2518
1.8 and 2.0 litre models:
Engine side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4533
Transmission side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7555
1Electrical system - general
1The electrical system is of the 12 volt
negative earth type, and consists of a 12 volt
battery, alternator with integral voltage
regulator, starter motor, and related electrical
accessories, components and wiring.
2The battery is of the maintenance-free
“sealed for life” type, and is charged by an
alternator, which is belt-driven from the
crankshaft pulley. The starter motor is of the
pre-engaged type, incorporating an integral
solenoid. On starting, the solenoid moves the
drive pinion into engagement with the flywheel
ring gear before the starter motor is
energised. Once the engine has started, a
one-way clutch prevents the motor armature
being driven by the engine until the pinion
disengages from the flywheel.
3It is necessary to take extra care when
working on the electrical system, to avoid
damage to semi-conductor devices (diodes
and transistors), and to avoid the risk of
personal injury. Along with the precautions
given in the “Safety first!” Section at the
beginning of this manual, take note of the
following points when working on the system.4Always remove rings, watches, etc. before
working on the electrical system. Even with
the battery disconnected, discharge could
occur if a component live terminal is earthed
through a metal object. This could cause a
shock or nasty burn.
5Do not reverse the battery connections.
Components such as the alternator, or any
other component having semi-conductor
circuitry, could be irreparably damaged.
6If the engine is being started using jump
leads and a slave battery, connect the
batteries positive to positive and negative to
negative. This also applies when connecting a
battery charger.
7Never disconnect the battery terminals, or
alternator multi-plug connector, when the
engine is running.
8The battery leads and alternator wiring
must be disconnected before carrying out any
electric welding on the vehicle.
9Never use an ohmmeter of the type
incorporating a hand-cranked generator for
circuit or continuity testing.
2Ignition system - general
1The ignition system is responsible for
igniting the air/fuel mixture in each cylinder at
the correct moment, in relation to engine
speed and load. A number of different types
of ignition systems are fitted to models within
the range. Ranging from a basic breakerless
electronic system, to a fully integrated engine
management system controlling both ignition
and fuel injection systems. Each system isdescribed in further detail later in this Section.
2The ignition system is based on feeding low
tension voltage from the battery to the coil,
where it is converted to high tension voltage.
The high tension voltage is powerful enough
to jump the spark plug gap in the cylinders
many times a second under high compression
pressures, providing that the system is in
good condition. The low tension (or primary)
circuit consists of the battery, the lead to the
ignition switch. The lead from the ignition
switch to the low tension coil windings and
the supply terminal on the electronic module.
The lead from the low tension coil windings to
the control terminal on the electronic module.
The high tension (or secondary) circuit
consists of the high tension coil windings, the
HT (high tension) lead from the coil to the
distributor cap, the rotor arm, the HT leads to
the spark plugs, and the spark plugs.
3The system functions in the following
manner. Current flowing through the low
tension coil windings produces a magnetic
field around the high tension windings. As the
engine rotates, a sensor produces an
electrical impulse that is amplified in the
electronic module and used to switch off the
low tension circuit.
4The subsequent collapse of the magnetic
field over the high tension windings produces
a high tension voltage, which is then fed to the
relevant spark plug through the distributor
cap and rotor arm. The low tension circuit is
automatically switched on again by the
electronic module, to allow the magnetic field
to build up again before the firing of the next
spark plug. The ignition is advanced and
retarded automatically, to ensure that the
spark occurs at the correct instant with the
engine speed and load.
5•2Engine electrical systems
Caution: Before carrying out
any work on the vehicle
electrical system, read through
the precautions given in the
“Safety first!” Section at the beginning of
this manual, and in Section 3 of this
Chapter.
Inspection
17Examine the distributor cap and rotor arm,
as described in paragraphs 6 and 7. Examine
the O-rings at the rear of the distributor body,
and on the rear of the shaft, and renew if
necessary.
Reassembly
18Reassembly is a reversal of dismantling,
ensuring that the thrustwashers are correctly
located. Note that the drive collar should be
refitted so that the drive peg on the collar is
aligned with the groove in the top of the
distributor shaft (it is possible to fit the drive
collar 180°out of position).
19Refit the distributor as described in
Section 18, and then check and if necessary
adjust the ignition timing, as described in
Section 21.
DOHC models (where
applicable)
20The distributor cap and rotor arm can be
examined as described in paragraphs 6 and 7.
21Ignition timing -checking and
adjustment
4
Note: Refer to Section 3 before proceeding. A
tachometer and a timing light will be required
during this procedure. For details of ignition
timing adjustment required to operate vehicles
on unleaded petrol, refer to Section 22.
14 NV and 16 SV models
Checking
1Start the engine and run it until it reaches
normal operating temperature, then switch
off.
2On 14 NV models, disconnect the vacuum
pipe from the distributor vacuum diaphragm
unit.
3On all models use a spanner applied to the
crankshaft pulley bolt to rotate the crankshaft
clockwise until the notch in the pulley’s
inboard rim aligns with the pointer protruding
from the oil pump housing. On 14 NV models,
where two notches (indicating 10°and 5°
BTDC respectively) are found, rotate the
crankshaft until the second notch (in thedirection of rotation -i.e. 5°BTDC) aligns. Use
white paint or similar to emphasise the pointer
and notch, to make them easier to see.
4Connect a timing light to No 1 cylinder
(nearest the timing belt end of the engine) HT
lead, also a tachometer; follow the equipment
manufacturer’s instructions for connection.
5Start the engine and allow it to idle -the
speed should be between 700 and 1000 rpm.
6On 14 NV models, aim the timing light at the
pointer and check that it is aligned with the
crankshaft pulley notch.
7On early 16 SV models, disconnect the
ignition timing basic adjustment coding plug.
This can be identified by a length of Black
wire joining Brown/Red and Brown/Yellow
wires in a connector plug clipped to the wiring
or heater/cooling system hoses beneath the
battery/ignition coil (see illustration, 16.1). This
causes the MSTS-i module to adopt its basic
adjustment mode, sending a constant firing
signal corresponding to 10°BTDC and
eliminating any advance below 2000 rpm. Aim
the timing light at the pointer and check that it
is aligned with the crankshaft pulley notch.
8On later 16 SV, C 16 NZ and C 16 NZ2
models, the coding plugs are no longer fitted.
For accurate checking, special Vauxhall test
equipment must be used which causes the
MSTS module to adopt its basic adjustment
mode.
9Without access to such equipment, it is
possible to check and adjust the ignition
timing, accurate results cannot be
guaranteed. Owners are therefore advised to
have this work carried out by a suitably
equipped Vauxhall dealer; at the very least,
make the initial setting yourself and then have
it checked as soon as possible.
10If you do attempt to check the ignition
timing yourself, note that the fixed reference
mark is now an extended line embossed on
the timing belt lower outer cover.
Adjustment
11If the notch and pointer are not aligned,
loosen the distributor clamp nut and turn the
distributor body slightly in the required
direction to align.
12Tighten the distributor clamp nut, and
check that the notch and pointer are still
aligned. 13Stop the engine, and disconnect the
timing light and tachometer.
14On 16 SV models, reconnect the basic
adjustment coding plug. On 14 NV models,
reconnect the vacuum pipe to the distributor
vacuum diaphragm unit.
Other models
15No adjustment of the ignition timing is
possible on 1.8 and 2.0 litre models, as the
adjustment is carried out automatically by the
electronic control module.
16The ignition timing can be checked by a
Vauxhall dealer using specialist dedicated test
equipment, if a fault is suspected.
22Ignition timing -adjustment
for use with unleaded petrol
3
14 NV models
1All models with the 14 NV engine have the
ignition timing adjusted for use with 95 RON
unleaded petrol before they leave the factory,
and no further adjustment is required.
2Leaded petrol (98 RON) can be used if
desired, with no adverse effects.
1.6, 1.8 and 2.0 SOHC models
Note: Models equipped with a catalytic
converter must be operated on 95 R0N
unleaded petrol at all times, and although an
octane coding plug may be fitted, it should
not be tampered with
3Models, other than 14 NV, are equipped
with an octane coding plug, which is located
Engine electrical systems 5•13
20.16B . . .and withdraw the sensor plate -
1.6 litre (Bosch distributor)
20.16C Sensor plate screw (arrowed) -
1.6 litre (Lucas distributor)
20.16A Remove the securing screws . . .20.15B . . .and disconnecting the small
wiring plug - 1.6 litre (Lucas distributor)
5
42Where applicable, screw the pressure-
proportioning valves into the base of the
cylinder.
43Refit the master cylinder, as described in
Section 15.
17Master cylinder (ABS) -
general
The master cylinder fitted to models with
ABS cannot be dismantled, and no attempt
should be made at overhaul.
If faulty, the complete unit must be
renewed, as described in Section 15.
18Vacuum servo - description
and testing
Description
1The vacuum servo is fitted between the
brake pedal and the master cylinder, and
provides assistance to the driver when the
pedal is depressed, reducing the effort required
to operate the brakes. The unit is operated by
vacuum from the inlet manifold. With the brake
pedal released, vacuum is channelled to both
sides of the internal diaphragm. However,
when the pedal is depressed, one side of the
diaphragm is opened to atmosphere, resulting
in assistance to the pedal effort. Should the
vacuum servo develop a fault, the hydraulic
system is not affected, but greater effort will be
required at the pedal.
Testing
2The operation of the servo can be checked
as follows.
3With the engine stopped, destroy the
vacuum in the servo by depressing the brake
pedal several times.
4Hold the brake pedal depressed and start
the engine. The pedal should sink slightly as
the engine is started.
5If the pedal does not sink, check the servo
vacuum hose for leaks.
6If no defects are found in the vacuum hose,
the fault must lie in the servo itself.7No overhaul of the servo is possible, and if
faulty, the complete unit must be renewed.
19Vacuum servo - removal and
refitting
4
Note: During the 1989 model year, some
vehicles were produced with the brake pedal
height incorrectly set, resulting in the brake
pedal resting approximately 15.0 mm (0.6 in)
above the clutch pedal instead of 4.0 mm
(0.16 in below). The correct pedal height can
be set by adjusting the vacuum servo
operating fork dimension, as described in
paragraphs 15 and 16
Removal
1Disconnect the battery negative lead.
2Working inside the vehicle, remove the
lower trim panel from the driver’s footwell.
3Disconnect the wiring plug from the brake
lamp switch, then twist the switch anti-
clockwise and remove it from its bracket.
4Pull the spring clip from the right-hand end
of the servo fork-to-pedal pivot pin.
5Using a pair of pliers, pull back the end of
the pedal return spring from the pedal, to
enable the servo fork-to-pedal pivot pin to be
removed. Withdraw the pivot pin.
6Remove the windscreen cowl panel, as
described in Chapter 11, then remove the
windscreen wiper motor and linkage as
described in Chapter 12.7Remove the coolant expansion tank as
described in Chapter 3.
8Pull the vacuum pipe from the brake servo.
9Unscrew the two securing nuts, and
carefully withdraw the brake master cylinder
from the studs on the servo. Move the master
cylinder forwards slightly, taking care not to
strain the brake pipes.
10Remove the two plugs covering the servo
securing bolts from the cowl panel (see
illustrations).
11Using a Allen key or hexagon bit, unscrew
the servo securing bolts and remove them
completely, then lift the servo from the
bulkhead (see illustrations).
12If desired, the mounting bracket can be
removed from the servo by unscrewing the
four securing nuts. Note that the bracket will
stick to the servo, as it is fitted with sealing
compound.
13The servo cannot be overhauled, and if
faulty, the complete unit must be renewed.
Refitting
14Before refitting the servo, check that the
operating fork dimension is correct as follows.
15Measure the distance from the end face of
the servo casing to the centre of the pivot pin
hole in the end of the operating fork. The
distance should be 144.0 mm (5.6 in). To
make accurate measurement easier, insert a
bolt or bar of similar diameter through the
pivot pin hole, and measure to the centre of
the bolt or bar (see illustration).
Braking system 9•15
19.11A Unscrew the securing bolts . . .19.15 Measuring the servo operating fork
dimension using a bolt inserted through
the pivot pin hole19.11B . . . and withdraw the servo
19.10B . . . to expose the servo securing
bolts19.10A Remove the plugs . . .
9
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)
32Release the securing clips and remove the
main outer timing belt cover, then unclip the
smaller outer timing belt cover from the
coolant pump.
33Turn the crankshaft through at least
quarter of a turn clockwise using a socket or
spanner on the crankshaft sprocket bolt.
34If the special gauge is available, place the
locked gauge at the centre of the belt run
between the coolant pump and the camshaft
sprocket. The gauge should locate on the
timing belt (see illustration).
35Slowly release the operating lever on the
gauge, then lightly tap the gauge two or three
times, and note the reading on the scale (see
illustration).
36If the reading is not as specified, loosen
the three coolant pump securing bolts, and
rotate the pump in the required direction to
achieve the desired reading on the gauge.
Rotate the pump clockwise to increase the
belt tension, or anti-clockwise to decrease the
tension.
37Lightly tighten the coolant pump securing
bolts.
38Remove the tensioning gauge, and turn
the crankshaft through one full turn clockwise.
39Re-check the belt tension as described in
paragraphs 4 and 5.
40If the tension is not as specified, repeat
paragraphs 6 to 9 inclusive until the desired,
consistent, reading is obtained.
41On completion of adjustment, remove the
checking gauge, tighten the coolant pump
bolts to the specified torque, and refit the
outer timing belt covers.
42If the special checking gauge is not
available, the timing belt tension can be
checked approximately by twisting the belt
between the thumb and forefinger, at the
centre of the run between the coolant pump
and the camshaft sprocket. It should just be
possible to twist the belt through 90°using
moderate pressure (see illustration). If
adjustment is necessary, continue as
described previously in this Section, but have
the belt tension checked by a Vauxhall dealer
using the special gauge at the earliest
opportunity. If in doubt, err on the tight side
when adjusting the tension, as if the belt is too
slack, it may jump on the sprockets, which
could result in serious engine damage.12Timing belt and tensioner 1.4
and 1.6 models (not C16 NZ2) -
removal, refitting and adjustment
3
Removal
1Remove the timing belt outer covers as
described in Section 11, paragraphs 1 to 5.
2To lock the tensioner in its slackest position
for removal and refitting, move the tensioner
indicator arm clockwise until the holes align in
the baseplate and the arm. Then insert a
close-fitting pin, such as a drift, to retain them
(see illustration). The tensioner can then be
unbolted, or the belt can be removed.
3Check that the tensioner roller rotates
smoothly and easily, with no noises or signs
of free play, roughness or notchy movement.
Check also that there is no sign of physical
wear or damage. If the tensioner is faulty in
any way, or if there is any reason to doubt the
continued efficiency of its spring, the
complete assembly must be renewed.
Refitting
4On refitting, ensure that the tensioner
baseplate lug engages with the hole in the oil
pump housing, then tighten the tensioner bolt
securely and remove the locking pin; the
tensioner should be quite free to move.
5Set the belt tension as described below.
Adjustment
6Whenever the timing belt is disturbed,
whether during belt renewal or any otherengine overhaul work, its tension must be set
on assembly - note that this procedure must
only be carried out on a cold engine.
7It is assumed that the belt has been
removed and refitted, i.e. that the crankshaft
pulley and timing belt outer covers are
removed, that the tensioner is unlocked (see
above) and that No 1 cylinder is in its firing
position (just before TDC on the compression
stroke). Temporarily refit the crankshaft pulley
bolt and remove the spark plugs so that the
crankshaft can be rotated easily.
8Note also that turning the coolant pump
with the precision required is a great deal
easier if a special spanner (Kent-Moore Part
No KM-421-A) is used. Alternatives are
available from manufacturers such as
Sykes-Pickavant (Part No 031300) (see
illustration).
9With the belt refitted and correctly routed
(see Section 11), ensure that the punch mark
on the crankshaft sprocket and the stamped
line on the camshaft sprocket are aligned with
their respective timing belt rear cover notches
(see illustrations).
10Tighten the belt by slackening its three
securing bolts, and turning the coolant pump
clockwise until the holes align in the tensioner
indicator arm and baseplate (the tensioner
indicator arm will then have moved fully
clockwise to its stop). Lightly tighten the
pump securing bolts, just sufficiently to
prevent the pump from moving.
11Using a spanner applied to the crankshaft
pulley bolt, turn the crankshaft smoothly
2A•16SOHC engine procedures
11.34 Tension blade KM-510-A correctly
positioned on timing belt. Belt must pass
through points A, B and C - SOHC engines11.42 Checking timing belt tension by
twisting belt through 90º between thumb
and forefinger
12.8 Using a special spanner to adjust the
timing belt by moving the coolant pump12.2 Using a close-fitting drift to lock the
tensioner. Note baseplate lug engaged in
oil pump housing (arrowed)
11.35 Note the reading on the scale of the
tension gauge -
1.6 litre engine
(without jerking it or the belt may jump a
tooth), through 2 complete revolutions (720°)
clockwise, until the camshaft and crankshaft
sprocket timing marks are once again aligned
as described in paragraph 13. The position of
the coolant pump must not alter.
12Slacken the timing belt by turning the
coolant pump anti-clockwise until the
tensioner’s indicator pointer is in the centre of
its baseplate notch; the timing belt tension is
then correct (see illustration). Tighten the
coolant pump bolts to the specified torque
wrench setting (see Chapter 3), then turn the
crankshaft through two further turns
clockwise and recheck the setting.
13If the pointer and notch are not aligned,
the operation must be repeated from
paragraph 7. On completion, refit all
components removed.
13Timing belt cover aperture,
1.4 and 1.6 models - general
General
The rear timing belt cover fitted to 1991 and
1992 model year 1.4 and 1.6 litre engines,
incorporates a small aperture just above the
oil pump housing. In certain circumstances, it
is possible for foreign objects, such as gravel,
to penetrate through this aperture and cause
the timing belt to jump a tooth on its
sprockets. For this reason, it is desirable to
cover the aperture to prevent the possibility of
this occurrence. A modified cover without an
aperture was introduced for 1993 models.
A piece of suitably moulded sponge rubber
(P/N 90469594), is available from Vauxhall
dealers to enable the aperture to be covered.
On models without power steering, the
sponge rubber can be inserted into the cover
aperture from above. If power steering is
fitted, the sponge rubber is inserted into place
from below. If access is difficult, particularly if
the drivebelt is of the ribbed V-belt type, it
may be easier to remove the alternator/power
steering pump drivebelt as described in
Chapter 5. Refit, and where applicable adjust,
the belt tension on completion.
14Timing belt and tensioner C16
NZ2, 1.8 and 2.0 litre - removal,
refitting and adjustment
3
Removal
1An alternative type of spring loaded
automatic timing belt tensioner is fitted to
these engines, from 1993 onward (see
illustration). The tensioner assembly is similar
to other automatic tensioners, but the removal
and refitting procedures vary as follows.
2The timing belt main outer cover may be
secured either by clips or by hexagon-headed
screws to the rear cover; in some cases, a
combination of clips and screws may be used.
3To release the belt tension before removal,
unscrew the timing belt tensioner securing
bolt slightly then, with a tool inserted in the
slot on the tensioner arm, turn the tensioner
arm until the timing belt is slack. If necessary,remove completely and examine the tensioner
as described in Section 12.
Refitting
4Refit the tensioner into position and tighten
the securing bolt slightly.
5Ensure 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 (see Chapter 3). Tighten the bolts
to the specified torque on completion.
6Refit the timing belt then tension it as
follows.
Adjustment
7Slacken the automatic tensioner securing
bolt and move the tensioner arm anti-
clockwise, until the tensioner pointer lies at its
stop. Tighten the tensioner securing bolt to
hold the tensioner in this position.
SOHC engine procedures 2A•17
12.12 Timing belt tension is correct when
the tensioner indicator pointer aligns with
the centre of the baseplate notch12.9B . . . and stamped line (A) on
camshaft sprocket with timing belt rear
cover notch (B)12.9A Align punch mark (A) on crankshaft
sprocket with timing belt rear
cover notch (B) . . .
2A
14.1 Timing belt automatic tensioner details (alternative type)
A Alignment lugs on coolant pump and cylinder block
B Tensioner pointer aligned with notch in tensioner bracket
1 Move the tensioner arm anti-clockwise to release the belt tension
2 Move the tensioner arm clockwise to tension the belt
8Turn 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 mark on the
camshaft sprocket is still aligned with the
notch in the timing belt rear cover. Slacken
the automatic tensioner securing bolt again
and move the tensioner arm clockwise, until
the tensioner pointer is aligned with the notch
in the tensioner bracket. 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
(see illustration).
9Tighten the tensioner securing bolt
securely. Turn the crankshaft through one
complete 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 12.
10With 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.
15Camshaft front oil seal -
removal and refitting
3
Removal
1The camshaft front oil seal may be renewed
with the engine in the vehicle without
removing the camshaft as follows.
2Remove the timing belt and the camshaft
sprocket, as described in Section 11.
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.
Refitting
4Clean the oil seal seat with a wooden or
plastic scraper.
5Grease the lips of the new seal, and drive it
into position until it is flush with the housing,
using a socket or tube. Take care not to
damage the seal lips during fitting.
6Refit the camshaft sprocket and the timing
belt and tension the timing belt as described
in Section 11.
16Camshaft rear oil seal -
removal and refitting
3
Removal
1The camshaft rear oil seal may be renewed
with the engine in the vehicle without
removing the camshaft as follows.
2Remove the distributor as described in
Chapter 53On 1.4 and 1.6 litre models (except C16
NZ2), the seal takes the form of an O-ring on
the rear of the distributor body. Prise off the
old O-ring carefully, using a screwdriver.
4On C16 NZ2, 1.8 and 2.0 litre models, prise
the seal from the camshaft housing
Refitting
5 On 1.4 and 1.6 litre models (except C16
NZ2), fit the new O-ring, and refit the
distributor as described in Chapter 5.
6On C16 NZ2, 1.8 and 2.0 litre models, fit the
new seal so that it is flush with the end of the
housing, then refit the distributor components
as described in Chapter 5.
17Camshaft housing and
camshaft -general
Note: The engine must be cold when
removing the camshaft housing. Do not
remove the camshaft housing from a hot
engine. New cylinder head bolts must be used
on refitting and sealer will be required when
refitting the camshaft housing. Also see
paragraph 3 before starting work:
General
1The camshaft can only be removed without
disturbing the housing, if a special tool is
available to depress the cam followers whilst
the camshaft is withdrawn.2If such a tool is available, the camshaft can
be removed, after removing the timing belt
and camshaft sprocket as described in
Section 11.
3If the special tool is not available, the
camshaft housing must be removed. Since
the cylinder head bolts must be removed, it is
strongly recommended that a new cylinder
head gasket is fitted. If the gasket is not
renewed, and it “blows” on reassembly, the
cylinder head will have to be removed to
renew the gasket, and another new set of
bolts will have to be obtained for refitting. You
have been warned!
4Removal and refitting of the camshaft
housing is described in Section 18, along with
cylinder head removal and refitting. If it is
decided not to disturb the cylinder head, the
relevant paragraphs referring specifically to
cylinder head removal and refitting can be
ignored.
5Removal of the camshaft from the housing
is described in Section 18.
18Camshaft housing and
camshaft - dismantling,
inspection and reassembly
4
Dismantling
1With the camshaft housing removed from
the cylinder head as described in Section 18,
continue as follows.
2Remove the distributor and it’s
components as described in Chapter 5 and
on C 16 NZ2, 1.8 and 2.0 litre, carefully prise
out the camshaft rear oil seal.
3On carburettor models, remove the fuel
pump, referring to Chapter 4A, if necessary.
4Working at the distributor end of the
camshaft, unscrew the two camshaft
thrustplate securing bolts, using an Allen key
or hexagon bit (see illustration).
5Withdraw the thrustplate, noting which way
round it is fitted (see illustration).
6Carefully withdraw the camshaft from the
distributor end of the camshaft housing,
taking care not to damage the bearing
journals (see illustration).
2A•18SOHC engine procedures
14.8 Timing belt adjustment
1 Alignment for new belts
2 Alignment for ‘run-in’ belts (gap is
approximately 4 mm to the left of centre)
18.4 Camshaft thrustplate and
securing bolts -
1.6 litre engine