Water Pump — checking, removing and installing (Mazda Capella GC)

Examination

A faulty water pump can cause the engine to overheat and fail (the engine is not cooled by the flow of circulating coolant).

There are three ways to check the water pump's performance without removing it from the engine. If the pump is faulty, it should be replaced or repaired.

Warm up the engine to operating temperature and clamp the upper radiator hose.

If the pump is working properly, then when you release the hose you will feel a push from the pressure of the coolant.

The water pump body is equipped with inspection holes for fluid leakage. If the pump is not sealed properly, a small leak will be observed through these holes. To check for a leak through the pump, remove the lower timing belt cover and shine a powerful light onto the bottom of the pump housing from the underside of the vehicle.

If the water pump shaft bearings fail, a sharp squealing sound will be heard from the front of the engine. Shaft wear can be felt by the play when the pump pulley swings up and down.

All pump parts are interchangeable, but repair work should be entrusted to a specialist or the pump should be taken to a service center, as special tools for pressing will be required.

Removal and installation

Please read the warning in section 2.

Drain the coolant.

Remove the timing belt covers and timing belt. Remove the timing belt tensioner roller.

Disconnect the inlet hose from the water pump.

Loosen the water pump mounting bolts.





Using a large screwdriver or appropriately sized pry bar, pry the water pump out while rocking it to disengage the pump gear (figure 5.7).

With the water pump moved forward, remove the bolts and disconnect the inlet pipe.

Remove the water pump from the engine compartment.

Thoroughly clean the pump contact surfaces from any remaining gasket material. Inspect and clean the annular groove for the sealing gasket.

Lubricate the O-ring with petroleum jelly and place it into the groove. Before installation, lubricate both parts of the gasket with sealant.

Install the water pump in place and attach the inlet pipe. Tighten the two pump mounting bolts by hand.

Install the remaining bolts and tighten them crosswise to the specified torque.

Connect the inlet hose.

Install the timing belt and belt covers.

Fill the cooling system with antifreeze.