How to tell if a water pump is going bad

The water pump drives coolant through your car's cooling system, keeping the temperature balanced so that your engine does not overheat. The pressurised coolant pumps through the cooling system continuously, but with careful maintenance, your water pump should last well over 100,000 miles. Without proper maintenance, your water pump will lose its bearings or break a seal, or a timing or fan belt will break, causing the radiator-to-engine circulatory process to fail. Then it is time to replace your water pump and its tangent parts.

Open the bonnet of your vehicle.

Locate the fan belt or the timing belt around a pulley system. The water pump will be next to the pulleys and the radiator. There will be a rubber hose connecting the water pump to the radiator, secured by two silver clamps.

Listen carefully for a howling sound from your water pump while the engine idles. This will not resemble a fan belt's squeal. Within the water pump are bearings that can wear out, causing your pump to leak coolant. You may notice drips or small puddles of coolant on the ground.

Watch for coolant weeping. Coolant will leak if your water pump has a broken seal or a "weep hole."

Turn on your passenger compartment heat full blast. If your vehicle is not pumping coolant through the heating core, then your water pump needs to be replaced.

Pull over and call for help if your vehicle begins to overheat; you will notice steam coming from under the hood or your engine's temperature gauge will be in the red. Your water pump needs to be replaced immediately, and your engine and cooling system may need significant service.


Consult your vehicle's repair guide for specific repair information for your make and model. Replace the fan clutch, pulley or timing belt, and radiator hose whenever you replace the water pump or your new pump won't last.


Never check for a worn fan clutch or bad water pump by physically checking your fan for looseness with your hands. Fans can start at any time.

Things You'll Need

  • Fan belt
  • Timing belt
  • Mechanical fan
  • Fan clutch
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About the Author

Cheryl Hosmer teaches online courses in writing and community journalism. She has written for various newspapers since 1983. She teamed up with author Marshall Terrill in 2001 as an editor of celebrity biographies. Hosmer holds a Bachelor of Arts in interdisciplinary studies from Madonna University. Her educational emphasis was poverty studies and journalism.