The water pump (technically the coolant pump) is powered by the engine and circulates liquid coolant through the engine cooling system. Leaks and noise are signs of water pump failure, which can be caused by age and wear or overheating conditions, and are often caused by other faults in the system. It’s driven by a belt (whether a dedicated serpentine or rarely by the timing belt), so proper belt maintenance is critical to its operation. Because of its location, it may be wise to replace an older water pump, even if it’s still functioning, while replacing a timing belt because the labor involved is costly.
