🔍 Key Concepts

• Compare how a Bendix-drive engages the ring gear (inertia and a helical screw on the armature shaft) versus an overrunning clutch drive (separate clutch/pinion assembly moved by a shift fork or lever). • Note what the solenoid plunger (labeled near C–F) is mechanically connected to in the illustration, and how it moves the pinion into mesh. • Remember that single-phase 110 V induction describes a motor type, not a starter drive/clutch mechanism on a diesel engine.

💭 Think About

• Look closely at the pinion gear end of the starter: do you see a threaded helical shaft for the pinion to ‘screw’ along, or do you see a collar and lever that physically shifts a clutch/pinion assembly? • Ask yourself: once the engine starts and spins faster than the starter, what feature in this drawing would protect the starter armature from being driven at excessive speed? • Which answer choices describe a mechanical drive/clutch and which describe an electrical motor type or unrelated mechanism?

✅ Before You Answer

• Identify whether the pinion is mounted on a helical threaded shaft (typical of Bendix) or on a clutch hub with rollers/sprags and a shift collar (typical of overrunning clutch). • Confirm that the solenoid plunger is linked to a shift lever/fork that slides the pinion assembly, rather than depending only on inertia to move the pinion. • Eliminate any option that does not describe a starter drive/clutch mechanism appropriate for a heavy-duty diesel engine.