The cooling power of the Pontiac water pumps is the only way your engine's temperature can be maintained at a specific level so the maximum performance of the engine can be obtained. Most Pontiac water pumps last for many years on the vehicles where they are mounted. This is an all metal engine component except for the seal on the shaft that protrudes out the front of the pump where the pulley is attached. The shaft is necessary since it is how the centrifugal power is supplied to turn the impeller on the inside of the water pump creating the flow of coolant through the engine. A seal on this shaft holds the coolant in the water pump and prevents it from escaping. This is made of a polymer and is the only component on this Pontiac engine part that will wear out in time requiring the water pump to be in need of replacement. When the seal on the pump begins to wear, a coolant leak will occur. There is a small hole in the bottom of the pump that permits the coolant to leave it and makes it possible for the owner of the Pontiac to know there is a problem with this engine cooling component. Because of the location of this hole being on the bottom of the pump, the first indication the owner of the vehicle has that there is a problem is when a puddle of coolant is noticed on the pavement. The hardest part of replacing the water pump on a Pontiac engine is actually gaining access to it. Before this component can be removed, coolant hoses, radiator shrouds and the belt system on the front of the engine will have to be removed. Once they are removed, the part will be easily replaced.