Ignition System Check; Idle Speed And Mixture Adjustments; Carburettor Models - Opel Kadett Owner's Manual

15 Refit the belt, and tension it as described
previously. Note that when a new belt has
been fitted it will probably stretch slightly to
start with and the tension should be
rechecked, and if necessary adjusted, after
about 5 minutes running.

10 Ignition system check

Models with contact breaker
ignition system
1 Renew the contact breaker points and
adjust the gap and dwell angle as described in
Chapter 5B. After adjustment put one or two
drops of engine oil into the centre of the cam
recess where appropriate and smear the
surfaces of the cam itself with petroleum jelly.
Do not over-lubricate as any excess could get
onto the contact point surfaces and cause
ignition difficulties.
2 The spark plug (HT) leads should also be
checked.
3 Ensure that the leads are numbered before
removing them, if not make identification
marks to avoid confusion when refitting. Pull
the leads from the plugs by gripping the end
fitting, not the lead, otherwise the lead
connection may be fractured.
4 Check inside the end fitting for signs of
corrosion, which will look like a white crusty
powder. Push the end fitting back onto the
spark plug ensuring that it is a tight fit on the
plug. If not, remove the lead again and use
pliers to carefully crimp the metal connector
inside the end fitting until it fits securely on the
end of the spark plug.
5 Using a clean rag, wipe the entire length of
the lead to remove any built-up dirt and
grease. Once the lead is clean, check for
burns, cracks and other damage. Do not bend
the lead excessively or pull the lead
lengthwise - the conductor inside might
break.
6 Disconnect the other end of the lead from
the distributor cap. Again, pull only on the end
fitting. Check for corrosion and a tight fit in the
same manner as the spark plug end. If an
ohmmeter is available, check the resistance of
the lead by connecting the meter between the
spark plug end of the lead and the segment
inside the distributor cap. Refit the lead
securely on completion.
7 Check the remaining leads one at a time, in
the same way.
8 If new spark plug (HT) leads are required,
purchase a set for your specific car and
engine.
9 Remove the distributor cap, wipe it clean
and carefully inspect it inside and out for signs
of cracks, carbon tracks (tracking) and worn,
burned or loose contacts; check that the
cap's carbon brush is unworn, free to move
against spring pressure and making good
contact with the rotor arm. Also inspect the
cap seal for signs of wear or damage and
10.9a Remove the distributor cap . . .
renew if necessary. Remove and inspect the
rotor arm (see illustrations). It is common
practice to renew the cap and rotor arm
whenever new spark plug (HT) leads are fitted.
When fitting a new cap, remove the leads
from the old cap one at a time and fit them to
the new cap in the exact same location - do
not simultaneously remove all the leads from
the old cap or firing order confusion may
occur. On refitting ensure that the arm is
securely pressed onto the shaft and the cap is
securely fitted.
10 Even with the ignition system in first class
condition, some engines may still occasionally
experience poor starting attributable to damp
ignition components. To disperse moisture a
moister dispersant aerosal can be very
effective.
Models with an electronic ignition
system
Warning: Voltages produced by
an electronic ignition system are
considerably higher than those
produced by conventional
ignition systems. Extreme care must be
taken when working on the system with the
ignition switched on. Persons with
surgically-implanted cardiac pacemaker
devices should keep well clear of the
ignition circuits, components and test
equipment.
11 Check the condition of the HT leads and
distributor components as described above in
paragraphs 3 to 10.
12 Check the ignition timing (Chapter 5C).
11 Idle speed and mixture
adjustments
1 Before checking the idle speed and mixture
setting, always check first the following.
a) Check that the ignition timing is accurate
(Chapter 5B or 5C).
b) Check that the spark plugs are in good
condition and correctly gapped (Section
25).
c) Check that the accelerator cable and, on
carburettor models, the choke cable
Every 9000 miles
10.9b . . . and pull off the rotor arm from
the distributor shaft (1.6 litre model shown)
(where fitted) is correctly adjusted (see
relevant Part of Chapter 4).
d) Check that the crankcase breather hoses
are secure with no leaks or kinks (Chapter
2).
e) Check that the air cleaner filter element is
clean (Section 31).
f) Check that the exhaust system is in good
condition (see relevant Part of Chapter 4).
g) If the engine is running very roughly,
check the compression pressures as
described in Chapter 2.
2 Take the car on a journey of sufficient
length to warm it up to normal operating
temperature. Proceed as described under the
relevant sub-heading.
Note: Adjustment should be completed within
two minutes of return, without stopping the
engine. If this cannot be achieved, or if the
radiator electric cooling fan operates, wait for
the cooling fan to stop and clear any excess
fuel from the inlet manifold by racing the
engine two or three times to between 2000
and 3000 rpm, then allow it to idle again.

Carburettor models

3 Connect a tachometer in accordance with
the manufacturer's instructions.
4 If the idle speed is outside the specified
tolerance (see Specifications), turn the
adjustment screw as
illustrations). This will not alter the CO
content of the exhaust gas to any extent.
5 If an exhaust gas analyser is available,
check the exhaust gas CO content as follows.
11.4a Idle speed adjustment screw
(arrowed) - 32TL carburettor
1•11
1
necessary (see