The water pump is used to push coolant through a vehicle's cooling system. A water pump replacement is needed is the water pump begins to leak coolant and/or makes a rumbling sound. due to the bearings in the water pump starting o deteriorate. If the water pump fails then the engine could overheat resulting is major engine damage.
There are two ways the water pump is operated; either by a fan belt, or the timing belt.
To replace the water pump, the cooling system is drained and either the fan belt or timing belt and pulleys are removed. If the water pump is driven by a fan belt, the hose from the water pump to the radiator and the bolts securing the water pump to the engine are removed. Then the water pump is removed from the engine and the surface of the engine is cleaned. Finally an new water pump and gasket are installed and the cooling system filled with fresh coolant. If the water pump is driven by a timing belt, the the timing belt covers, and all related components are taken apart and the hardware that secures the water pump to the engine is removed, along with the water pump. The engine surface is cleaned and the new water pump and gasket is installed. Finally all the timing belt components, fan belt, and pulleys are reassemble and reinstalled and the cooling system filled with new fluid.
When performing a water pump replacement make sure to refer to the manufacturer guidelines found in your vehicle's owner's manual. They must be adhered by to maintain the validity of your new car warranty and extended auto warranty, if applied. If mechanical breakdown occurs due to the improper installation of the water pump, the warranty would not cover the car repair.