Volvo 120 Operating Instructions Manual page 28

FAULT TRACING
The information given below is only intended to serve as a guide in
localizing and temporarily correcting minor faults. After having carried
out any such measures, have them checked and adjusted by an experien-
ced mechanic.
The engine does start although the starter motor
turns it round at normal speed
1 Check that there is fuel in the tank.
2 If the engine is warm, starting should be done with the accelerator
pedal slowly depressed as far as it will go.
3 In wet weather the sparking plug insulators should be wiped clean
and the distributor cap removed and wiped dry if flash-over is sus-
pected.
4 Check that the fuel line connections on the pump and carburettor
are not leaking and that fuel is supplied to the carburettor.
5 If the engine is turned round for a while without having started, too
rich a fuel mixture can enter the cylinders resulting in the sparking
plugs becoming moist. Blow the cylinders clean by screwing off the
sparking plug and turning round the engine with the starter motor.
Dry the sparking plugs before fitting them.
If the engine misfires, the reason can be:
1 That one of the ignition cables has loosened in the distributor cover
or from the sparking plug.
2 That one or more of the sparking plugs is coated with soot or oiled
up, in which case the plug concerned should be cleaned or changed
and the sparking plug gap adjusted.
3 That the distributor cover and rotor arm can be cracked or damaged.
4 That one of the ignition cables is in a poor condition.
5 That the contact breaker gap in the distributor is insufficient or
non-existent.
6 That the contact breakers are badly burned.
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