TUBE AS 2906883 - Caterpillar

Illustration 1 g00718866
Starting motorThe starting motor rotates the engine flywheel. The engine will run when the engine flywheel has reached an adequate speed. The starting motor has a solenoid. Electricity will cause the solenoid to move the pinion drive toward the flywheel ring gear of the engine when the ignition switch is activated. The electrical contacts in the solenoid close the circuit between the battery and the starting motor. This causes the starting motor to rotate. Damage to the armature can be caused by excessive speeds. The overrunning clutch portion of the pinion drive prevents damage to the armature when the engine begins to run. This is done by breaking the mechanical connection. The pinion will stay meshed with the ring gear however, until the ignition switch is released. A return spring in the overrunning clutch returns the clutch assembly to the rest position.