Coolant leak, can't pinpoint.

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AN292

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I was having a decent leak, filling the reservoir every few days. I used a radiator stop leak and that fixed it right up for a few months. Now the leak is back, I used the stop leak again and it didnt seem to stop it. Im seeing puddles now, not just little drips.

So, I cant exactly pin point where its coming from, I will have to get underneath it one of these days.

The leak is near the front, so I'm thinking water pump.

Is there a known spot where coolant leaks that I dont know about?

Thanks
 
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My son was having the same problem with our 2001 last fall (he had it with him at college) and couldn't pinpoint where the leak was. He said the coolant puddle overnight would be under the center of the motor. I told him to remove the front splash shield that way if the leak was near the front of the engine it would be easier to pinpoint by not running down the splash shield.

He found it was coming from the bottom of the water pump. We replaced the water pump (and the fan clutch). When we pulled the water pump off, the internal vanes just disintegrated. It was the original pump, 220k miles.
 

Larryjb

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A coolant pressure tester was one of the best purchases I made. You hook it up and pressurize the cooling system then look around all over the place for where the leak is. I have found so many leaks this way.

Some have said a few leaks don't show until the engine is warm. However, so far I have caught every leak:

Thermostat housing leak
Water pump leak (one didn't show until I left the tester on overnight, saw the puddle in the morning underneath the water pump)
heater hose connection leak
radiator tank leak
cracked head leak (required removal of the valve cover)

Some of these leaks were on multiple vehicles which means I have caught about 10-15 leaks over the years this way.

The only leak that didn't show wasn't a leak until it broke while driving. So, I recommend changing all plastic T's every coolant change using GM T's, not Dorman.
 

Doubeleive

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Like Tom said look directly under the water pump, you will need a flashlight and look kind of from the bottom side at a angle, just shine your flashlight up to the bottom of the water pump, if you have one of those telescoping mirror's (there like $2 at the autoparts store) then you can look at it from up top by angling the mirror down under the water pump and using your flashlight to shine the light at the mirror reflecting up under the water pump.
 

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