Starter motor - description and testing

Electrical system / Starter motor - description and testing

1 The starter motor may be one of two different makes. Both are of pre-engaged type.

2 This type of starter motor incorporates a solenoid mounted on top of the starter motor body. When the ignition switch is operated, the solenoid moves the starter drive pinion, through the medium of the shift lever, into engagement with the flywheel starter ring gear. As the solenoid reaches the end of its stroke, and with the pinion by now partially engaged with the flywheel ring gear, the main fixed and moving contacts close and engage the starter motor to rotate the engine.

3 This pre-engagement of the starter drive does much to reduce the wear on the flywheel ring gear associated with inertia type starter motors.

4 If the starter fails, some fault-finding can be done with it still on the car. Check the ignition warning light comes on, and does not go out when the starter is switched on. If it goes out, the fault is probably in the battery. If it stays bright, get an assistant to work the switch, whilst listening to the starter. Listen to find out if the solenoid clicks into position. If it does not, pull off the solenoid wire, and check it with a test bulb. If the wire is live when the key is turned, but the solenoid does not move, take off the starter and remove it to the bench for overhaul.