Question 209Motor Plants - 1st Asst/Chief

The correct answer is D) Secure the fuel supply and block the air intake. To stop an overspeeding diesel engine, the best approach is to cut off both the fuel supply and the air intake. This is because a diesel engine requires a specific air-fuel mixture to operate. By securing the fuel supply and blocking the air intake, you effectively starve the engine of the necessary components to continue running, which will cause it to stall and stop. The other options are not as effective. Disconnecting the battery cables from the starting motor (A) would not stop a runaway engine, as the engine is already running. Draining the hydraulic fluid from the governor sump (B) would not directly address the issue of overspeeding. Blocking the flow of cooling air to the radiator (C) may eventually cause the engine to overheat, but it would not immediately stop the overspeeding.