Some diesel engines are fitted with a thermometer in the cooling water outlet from each cylinder. If the cooling water temperature from all cylinders begins to rise above normal, you should suspect __________.

Correct Answer: Option D — overloading in all cylinders

When cooling water temperatures rise uniformly across all cylinders, the root cause is systemic rather than localized. Engine overloading increases total thermal energy input across all combustion chambers, raising the bulk cooling water temperature.