What occurs if cutting off the fuel supply does not stop a diesel engine?

When cutting off the fuel supply to a diesel engine does not stop it, the most likely scenario is a runaway diesel condition. This phenomenon occurs because diesel engines can potentially operate on a variety of fuels if the primary fuel source is interrupted. In particular, if there is oil or another combustible substance present (for example, engine lubricating oil), the engine may continue to run despite the fuel supply being cut off.

A runaway diesel engine can lead to extremely high RPMs, which may result in catastrophic engine failure due to overspeed. This can happen because diesel engines do not rely on spark plugs to ignite fuel, but rather on compression; thus, any flammable substance seeping into the cylinders can keep the engine running. Understanding this risk is crucial for safe operations, as it may require additional measures to shut down the engine, such as blocking the intake air supply, in order to stop the combustion process effectively.

The other options may relate to engine performance issues but do not directly relate to the scenario of an engine continuing to run after the fuel supply has been cut off. Excessive pressure and overheating could be potential consequences of prolonged runaway conditions, but they do not directly explain what happens when the fuel supply is disconnected. Fuel starvation refers to the