If your Ford Focus water pump, which sends coolant to the machine, is not working, the machine is at risk of overheating. You need to fix the cooling system by replacing the water pump. The exact way to access it is by removing the parts depending on the type of machine. It is better to try to change it yourself only if your Focus has a Zetec type engine.
Disconnect the negative battery cable from the car battery. Drain the cooling system into a large container by removing the drain plug from the radiator and then from the engine block.
Lift the front end of the car and support it on the hydraulic jack. Unscrew and remove the lower drive belt cover.
Loosen the water pump pulley bolts but do not remove them yet.
Remove the drive belt by turning the center of the tensioning bolt clockwise and, using the spanner wrench, remove it so you can free it from the pulleys. Remember, for later re-installation, how the belt was arranged on the pulleys.
Remove the water pump pulley by removing the remaining bolts.
Disconnect the cooling hose from the water pump housing and then remove the timing belt from the tensioner pulley.
Unscrew and remove the water pump from the water pump housing.
Check and make sure the mating surface of the replacement pump is clean, then install a new gasket on it. If the pump uses a seal ring, then use a new one lubricated with engine coolant.
Install the pump into its housing by tightening the 156 in-lb. bolts.
Screw the tensioner roller timing belt in place by tightening the 18 ft-lb. bolts and connect the coolant hose to the water pump housing.
Reconnect the water pump pulley by tightening the 18 ft-lb. bolts.
Install the drive belt by loosening the tensioner and sliding it to the back of the pulleys, the same way it was originally located. Reconnect the lower drive belt cover.
If the old coolant is dirty, refill the radiator with fresh engine coolant in a 50/50 mixture of antifreeze and water.
Warnings
If the Focus has an SPI engine, the timing belt clogs the water pump. Given the complexity of timing belt removal, in this case it is best to leave the repair work to professionals.