Circuit Operation

The solenoid windings are energized when the ignition switch is turned to the START position. This causes the pinion to engage the engine flywheel ring gear and the solenoid main contact switch to close, which cranks the engine. When the engine starts, pinion overrun protects the armature from excessive speed until the switch is opened. Once the solenoid windings are de-energized, the return spring causes the pinion to disengage. The switch opens immediately when the engine starts to prevent excessive overrun.