A diesel engine operates erratically, overspeeds, and fails to restart when cranked at normal speed. Which of the following problems is the most likely cause for the engine failing to restart?

Correct Answer: Option C — Failure to reset the overspeed trip

An emergency overspeed trip positively shuts off fuel delivery by securing the fuel racks or stopping fuel injection. Following an overspeed event and subsequent shutdown, the mechanical or hydraulic trip mechanism must be manually or automatically reset before fuel control linkage can operate and allow the engine to restart.