Water Pump Inspection

Water pump failure can lead to serious consequences, up to complete engine seizure caused by overheating.

There are two ways to check water pump operation without removing it from the engine. A defective pump must be replaced. Either a new or a remanufactured assembly may be used as the replacement.

The water pump is equipped with weep (or vent) holes. If the seal fails, coolant will seep out of these holes. Prepare a flashlight and a small mirror, then remove the timing belt cover. Using the flashlight and mirror, locate the weep holes on the lower/rear part of the pump and check whether coolant is seeping from them.

If the pump shaft bearings fail, a howling noise may be heard from the front of the pump while the engine is running. This should not be confused with the squeal of the drive belt when belt tension is reduced. Bearing wear can be detected by play when rocking the pump pulley (be sure to turn off the engine first).

Pump wear is sometimes not visible externally, so during an engine overhaul it makes sense to disassemble the unit and visually inspect its internal components. Pump efficiency often decreases due to severe corrosion damage to the impeller vanes.