If an airlock develops in the fuel system of a diesel engine, what would happen?

When an airlock occurs in the fuel system of a diesel engine, it disrupts the normal flow of fuel to the engine. Diesel engines rely on a continuous supply of fuel to maintain operation. An airlock creates pockets of air that interrupt this flow, leading to insufficient fuel reaching the engine's combustion chamber. As a result, the engine may fail to maintain combustion and will shut down due to a lack of fuel. This is critical because diesel engines are designed to operate with diesel fuel being continuously fed into the combustion system.

Having an airlock can prevent the engine from starting if it happens before operation, but in this scenario, the question focuses on the consequences of air intrusion during operation, where the lack of fuel supply would certainly lead to an engine shutdown. Other options suggest continual running or overheating, which would not be possible in the presence of an airlock that hampers fuel delivery.