First a mechanic will make sure your water pump is in fact faulty.A good mechanic will also sell a new thermostat with any cooling system repair. This is considered very cheap insurance.

The belt that runs the water pump will also be checked and should be replaced if it is cracked or has a high glaze from the pullies. On most modern day vehicles there is only one belt, this multi accessory belt is referred to as a serpentine belt because of its snake like appearance as it weaves its way through the alternator,a/c compressor, power steering pump, water pump, smog pump, and around the crank shaft pulley that drives all of these accessories.

The cooling system must then be drained and the coolant recycled so that it doesn't pollute our environment by contaminating our soil, or our drinking water.

Antifreeze has a poly glycol base and is deadly if swallowed. The most deaths seen from antifreeze is our animal population because it has a sweet taste and animals have no idea that they are actually killing themselves by drinking this sweet tasting waste.

The drive belt and miscellaneous brackets are removed and then the water pump itself is then removed. The surfaces on the engine block that mate with the surfaces on the water pump are cleaned of all old gasket material to insure that the new gasket seals the water pump to the engine block since coolant passes between the two and there must not be any leaks.

Coolant under pressure will not boil til it reaches approximately 220 degrees, if there is a coolant leak the boiling point will be reduced to approximately 100 degrees and engine overheating will occur.

After the new water pump is installed the mechanic will reinstall all the parts he had to remove for the replacement. Then the coolant is replaced in the vehicle at a ratio of 50% water and 50% coolant. The air must be removed from the cooling system, and a cooling system cycle must be performed. This is done by running the engine until it reaches operating temperature, at operating temperature the thermostat will open, aprx. 190 degrees. The thermostat is designed to hold the water in the engine block til it reaches a temperature of about 190 degrees, at that point it opens and the coolant that has been cooling off during this process in the radiator is forced into the engine block and the coolant from the engine block is forced into the radiator to cool off as the thermostat closes and the cycle starts all over again.

The overflow bottle for the cooling system must be filled to the manufacturers proper marking.

The overflow bottle is not only used for overflows, it is also a means of topping off the cooling system.

The vehicle is now ready for the test drive and then if no problems occur the vehicle is returned to the customer and ready for use.

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