Question 9Motor Plants - 1st Asst/Chief

The correct answer is B) Excessive fuel injection. Explanation: Excessive fuel injection can cause the cylinder relief valves on a large, low-speed, propulsion diesel engine to lift. This is because an excessive amount of fuel injected into the cylinder can lead to a rapid rise in cylinder pressure, which in turn can cause the relief valves to open and release the excess pressure. The other options, such as plugged injector nozzles, incorrect crankshaft clearances, or very late injection timing, would not directly lead to the lifting of the cylinder relief valves.