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Q: water pump replacement. 2011 Buick Lacrosse

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hi. i have a quote for a water pump replacement. 2011 Buick Lacrosse. Does Also, I'm leaking fluid. the dealership says "we think it's the water pump because of trace fluid found near it". The pressure check evidently isn't finding a leak and yet my car is leaking pretty badly. it actually seems to lose the fluid after sitting and not cranked up. Any suggestions would be grateful.

My car has 46000 miles.
My car has an automatic transmission.

A: Hey there. It does sound as though you need...

Hey there. It does sound as though you need a water pump. Water pumps have very different sealing methods than every other component on your car. This is due to the rotating nature of the pump and the pressure in the cooling system. It is one of the most well known detail in the automotive industry that a water pump will leak when your car is in the process of cooling down or when it is cold.

As the motor warms up, it builds pressure in the cooling system that seals the front water pump seal. When the car is shut off, the water pump front seal will cool faster than the rest of the car and this creates a coolant leak. Its seems hard to believe that it would be able to leak a lot and then not at all, but they frequently do.

When a technician pressure tests a cooling system, it is simulating a hot cooling system. The same situation that the water pump is not leaking. When they do a visual inspection, they will see dried coolant coming from the water pump weep hole, but no actual coolant leaks.

This is a classic scenario that is very common. Rest assured that if my interpretation of your situation is correct, you will need a water pump replacement.

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