Starter Motor: Testing and Inspection

Fig. 3 Starter free speed test connections:

FREE SPEED TEST
With the circuit connected as shown in Fig. 3, use a tachometer to measure armature revolutions per minute. Failure of the motor to perform to specifications may be due to tight or dry bearings, or high resistance connections.

Fig. 4 Starter pinion clearance test connections:

Fig. 5 Checking pinion clearance:

PINION CLEARANCE
There is no provision for adjusting pinion clearance on this type motor. When the shift lever mechanism is correctly assembled, the pinion clearance should fall within the limits of .010 to .140 inch. When the clearance is not within these limits, it may indicate excessive wear of the solenoid linkage or shift lever yoke buttons.
Pinion clearance should be checked after the motor has been disassembled and reassembled. To check, disconnect motor field coil connector from solenoid terminal and insulate end. Connect one battery lead to solenoid switch terminal and the other lead to the solenoid frame, Fig. 4. Using a jumper lead connected to the solenoid motor terminal, momentarily flash the lead to the solenoid frame. This will shift the pinion into the cranking position until the battery is disconnected.
After energizing the solenoid with the clutch shifted toward the pinion stop retainer, push the pinion back toward the commutator end as far as possible to take up any slack movement; then check the clearance with feeler gauge, Fig. 5.