Auto Repair - Other

How to tell if a Cars Water Pump needs to be Replaced

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"How to tell if a Cars Water Pump needs to be Replaced"
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It’s the peak of summer, temperatures are in excess of 100 degrees and you’re caught dead in the middle of gridlock in rush hour traffic.  You’re A/C is blasting at full capacity, your temper is already short and as if things couldn’t get any worse, you’re menaced by a faint “pinging” sound that is resonating from your car engine.  You turn down the A/C for further observation and all of a sudden you observe that the needle on your heat gauge is bobbing eastward, your car is overheating. 

A car engine can reach temperatures anywhere from 190 to 220 degrees Fahrenheit.  However without sufficient coolant, temperatures that exceed this normal range can cause a car to become a literal “ticking time bomb.”  A properly functioning water pump circulates coolant between the engine and the radiator, to prevent overheating.  If a car overheats, significant and costly damage can occur to the engine. From piston damage to a blown head gasket, knowing the signs of a bad water pump can save you thousands.

Water pumps have seals and impellers that get worn over time.  If the shaft seal of the water pump is compromised, then coolant will begin to leak out.  If the impellers become broken or eroded, coolant cannot be properly pumped through the engine. This is a common occurrence in late model cars, as the impellers are plastic and can break more easily.

Symptoms of a Bad Water Pump

One of the most obvious signs of a failing water pump is loss of coolant.  Check for puddles underneath your vehicle when the car is parked, coolant tends to only leak when the car is not running.  Also, check your coolant reservoir.  If the reservoir is constantly low or empty, you could have either a bad water pump or more serious issue with the radiator or head gasket.

You can also check the water pump by evaluating the upper radiator hose.  First, inspect for any obvious leaks.  If none are detected, carefully (hose may be hot) squeeze the radiator hose while the car is running.  If you do not feel fluid circulating through the hose, then the water pump is not pumping coolant. 

Lastly, you may have to remove the water pump for further inspection.  If the pump shaft is loose or wobbles, then it needs to be replaced.  You should also check for worn seals, corrosion or any other visible signs of wear. The water pump impeller should move freely, if this does not occur, then the blades may be eroded which would prohibit the pump from circulating coolant.

In most cases, the symptoms of a failing water pump are easy to detect.  Catching them early is the key.  Otherwise, you could be looking at thousands in costly repairs that could have been easily avoided.

More about this author: Elaina Wicks

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