STARTING SYSTEM

Fig. 1: Terminal designation on starter

Fig. 2: Measure the pinion gap

Connect terminal S of starter switch to the positive terminal of the battery using a lead wire or equivalent.
Connect the starter body to the negative terminal of the battery.
If the switch assembly is working correctly, the pinion should be forced out. If the starter motor rotates, this is OK. Sometimes current will flow through the pull in coil to the motor and cause this.
With the pinion forced outward, measure the pinion gap. It should be between 0.02–0.08 inch (0.5–2.0mm).
Unfasten all connections.
Disconnect the wire at terminal M, and attach a lead wire or equivalent between terminal M and the battery positive terminal.
Connect a ground lead between the stator body and the negative terminal of the battery.
If the switch assembly is functioning correctly, the pinion should return it its original position.

Fig. 3: Schematic for testing the starter

Refer to the illustration and connection ammeter, voltmeter and switch.
With the switch ON, adjust the variable resistance to obtain 11.0 volts.
Take an ammeter reading and record the starter speed.
If the starter is functioning properly, at 11.0 volts, with a maximum of 90 amps, the starter will be rotating at 3000 rpm.

Refer to the illustration and connection ammeter, voltmeter and switch.
Apply braking torque to the starter.
Measure the current draw and starter speed at 7.7 volts.
If the starter is functioning correctly, at a load of 7.7 volts and 7 ft. lbs. (10 Nm) of torque, the should be a maximum current draw of 300 amps at 1000 rpm.

Refer to the illustration and connection ammeter, voltmeter and switch.
with the starter stalled, or not rotating, measure the torque developed and the current draw when the voltage is adjusted to 4.0 volts.
If the starter is functioning properly, at 4.0 volts, the starter will draw a maximum of 980 amps at a torque of 17 ft. lbs. (23 Nm).