1. Water pump failure can cause overheating and serious engine damage.
2. There are three ways to check the operation of the water pump without removing the pump from the engine. If the pump is faulty, replace it.
3. Start the engine, let it warm up to operating temperature and squeeze the upper radiator hose. Release the hose. If the water pump is working properly, a pressure wave should be felt at this point.
4. The water pump has bypass or vent holes. If the pump seal is damaged, small leaks will occur from these holes. To find these leaks, it is necessary to remove the bottom cover of the toothed belt and inspect the pump housing from under the car, shining a flashlight on yourself.
5. If the water pump shaft bearings have become unusable, when the engine is running, a characteristic sound resembling a creak will be heard from its front end.
6. All pump components are replaceable, but this requires special tools, so the job should be done by a Mazda dealer or other specialist.