Proper operation of the cooling system is very important, as it protects the engine from overheating and provides the passengers with hot air inside the car. The coolant circulation in the system is controlled by the water pump - one of its most important elements. If the pump leaks the coolant or is noisier than usually, it means that its gaskets or roller bearing are worn.The pump needs replacing in either case.
If the water pump is driven by the timing belt, it should be replaced together with the timing gear A damaged roller bearing may block the pump drive and, consequently, the other elements driven by the belt
How does the cooling system work?
In order for the cooling system to work properly, i.e. to take excess heat from the engine and release it through the radiator, the coolant must be constantly in motion. It should flow around the engine block and the cylinder head and should be transported by means of hoses into the radiator and then back into the engine.
How does the water pump work?
The water pump forces the coolant to flow constantly around the system. The pump is driven from the engine by means of a drive belt or a timing belt. The pump is equipped with a rotor located on a shaft which turns and forces the coolant to flow.
How is the water pump changed?
The shaft's bearing or its sealing gradually wears and fails. When this happens, the pump works noisily and leaks. If this is the case, it must be changed. To do this, you need to loosen the belt. If the pump is driven by the timing belt, you have to detach it. Then you have to remove the coolant from the system to prevent it from leaking out in an uncontrolled way after removing the pump. Next, you have to remove the bolts holding the pump's housing to the engine.
How is a new water pump fitted in?
After removing the faulty pump you have to remove what's left of the old gasket. The new pump should be fitted on a new gasket. After fitting the new pump in, reattach the belt and, if necessary, adjust it. All you have to do now is refill the system with fresh coolant and start the engine to check if the system works properly. Make sure that there are no leaks.
What else to keep in mind?
Each repair of the cooling system is a perfect opportunity to check if the coolant's concentration is sufficient to protect it against boiling and freezing within a specified temperature range.