Initiating Cranking

As this electrical connection is being made at the terminal end of the solenoid, the mechanical motion of the solenoid plunger is being transferred to the drive pinion through the shift lever, bringing the pinion gear into mesh with the flywheel ring gear. When the starter motor receives current, its armature starts to turn. This motion is transferred through an overriding clutch and pinion gear to the engine flywheel and the engine is cranked.

With this type of solenoid-actuated direct-drive starting system, teeth on the pinion gear might not immediately mesh with the flywheel ring gear. If this occurs, a spring located behind the pinion compresses so that the solenoid plunger can complete its stroke. When the starter motor armature begins to turn, the pinion teeth will mesh with the flywheel teeth under spring pressure.

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