A failing gasoline engine water pump often produces a squealing noise from the bearing. This gasoline engine water pump may leak coolant from the shaft seal when worn. The first sign of a bad gasoline engine water pump is often a puddle under the car.

A visual inspection of the gasoline engine water pump can reveal rust or corrosion on the housing. The pulley of a gasoline engine water pump should spin freely without grinding. A loose belt can mimic the symptoms of a faulty gasoline engine water pump.

Replacing a gasoline engine water pump requires draining the cooling system first. The new gasoline engine water pump should come with a new gasket or O‑ring. A torque wrench is needed to properly secure the gasoline engine water pump bolts.

The impeller of a gasoline engine water pump can be inspected after removal. A cracked gasoline engine water pump housing is not repairable and must be replaced. The thermostat should be tested when replacing a gasoline engine water pump.

A gasoline engine water pump with a plastic impeller is lighter but less durable. The coolant type affects the life of a gasoline engine water pump seal. Using distilled water and antifreeze extends the life of a gasoline engine water pump. Timely replacement of a gasoline engine water pump avoids costly engine repairs.