Condenser (capacitor) - removal, testing and refitting

Ignition system / Condenser (capacitor) - removal, testing and refitting

The purpose of the condenser (sometimes known as the capacitor) is to ensure that when the contact breaker points open there is no sparking across them which would weaken the spark and cause rapid deterioration of the points.

The condenser is fitted in parallel with the contact breaker points. If it develops a short circuit it will cause ignition failure as the points will be prevented from interrupting the low tension circuit.

1 If the engine becomes very difficult to start (or begins to misfire whilst running) and the breaker points show signs of excessive burning, suspect the condenser has failed with open circuit. A test can be made by separating the points by hand with the ignition switched on. If this is accompanied by a bright spark at the contact points, it is indicative that the condenser has failed.

2 Without special test equipment, the only sure way to diagnose condenser trouble is to replace a suspected unit with a new one and note if there is any improvement.

3 To remove the condenser from the distributor, take out the screw which secures it to the distributor body and disconnect its leads from the terminals.

4 When fitting the condenser, it is vital to ensure that the fixing screw is secure. The lead must be secure on the terminal with no chance of short circuiting.