Starter Motor: Description and Operation

- The starter motor is a 12-volt unit that has a solenoid mounted on the drive end housing.
- The motor is energized when the starter solenoid contacts are closed.
- This action engages the starter drive with the flywheel ring gear, starting the engine.
- An overrunning clutch in the drive protects the starter from excessive speed when the engine starts.
- The current flows through the solenoid energizing coil until the solenoid plunger is at the end of its travel.
- The plunger then closes a set of contacts that bypass the energizing coil, letting the holding coil keep the starter drive engaged and passing starting current to the starter.