Pre-engaged starter- Return spring Solenoid Commutator Brushes Field windings Pinion Actuating arm

The pinion is moved by the solenoid; there is an initial period in which the motor turns slowly to allow engagement, so the whole operation is more gentle and causes less wear on the teeth.

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How the starting system works

To make an engine start it must be turned at some speed, so that it sucks fuel and air...