Checking the water pump

1. With the engine running, pinch the upper radiator hose and release gradually. With a working pump, fluid pressure should be felt in the hose.



2. The pump has a control hole for draining fluid (shown by arrow). If the pump seal fails, coolant flows out through the control hole. To find this hole, you need to highlight the space behind the driven flange of the pump, directly under the shaft.

3. Bearing wear can be detected by rocking the pump up and down and by a characteristic whine at the front of the engine. A slipping drive belt can also produce a sound close in tone, so an erroneous conclusion can be made about a pump malfunction. To eliminate sound from the belt, spray on a special compound for automobile belts.