Starter No-Load Test

CAUTION: Make sure that the starter motor is securely mounted in bench vise while energizing, as starter motor will move or jump. See STARTER under REMOVAL & INSTALLATION.

The starter no-load test will uncover such conditions as open or shorted windings, or rubbing starter motor armature. The starter motor can be tested at no-load, on the test bench only.

NOTE: A remote control starter switch should be used in the "S" 1-1 circuit for turning the starter motor ON and OFF during testing. See WIRING DIAGRAMS .

Make test connections with Rotunda Battery and Starter Tester (010-00725), or equivalent cables connected to starter motor, large enough to carry high current (the same as in the vehicle). See Fig 1 . The starter motor will run at no-load. Be sure that no current is flowing through ammeter (rheostat at maximum counterclockwise position). Determine exact reading on voltmeter.

Fig 1: Performing Starter No-Load Test
Courtesy of FORD MOTOR CO.
Disconnect starter motor from battery. Then reduce resistance of rheostat until voltmeter indicates same reading as that obtained while starter motor was running. The ammeter will indicate starter motor no-load current draw. See STARTER SPECIFICATIONS .
If current exceeds specification, check for rubbing starter motor armature, bent output shaft, binding bushings, or shorts in starter motor armature or brush holder.