The cranking circuit consists of the battery, starter motor, ignition switch, and related wiring.

These starter motors are not serviceable and are replaced as assemblies only.

When the ignition switch is turned to START, voltage is applied to the starter solenoid S terminal and the solenoid windings are energized. This causes the plunger to move the shift lever, which engages the pinion with the engine flywheel ring gear. The plunger also closes the solenoid contacts, applying battery voltage to the starter motor which cranks the engine.

When the engine starts, the pinion will over-run and spin at engine speed (rather than stater motor speed) to help prevent flywheel and starter motor damage. When the ignition switch is released (removing voltage from the solenoid) the plunger return spring disengages the pinion. In order to prevent excessive over-run, the ignition switch should be released as soon as the engine starts.