86 GT V6 4 speed

I have been working on tracking this down for weeks. Ever now and then when the car sits for 3 or 4 hours there will be an antifreeze puddle under the car. I never find it leaking while driving or right after running. It ranges from a couple of drops to about a cup or two. I have looked to find where it is coming from but everything is so wet I can't trace it. I clean everything up and it stays dry for a couple of days. Only once have I ever seen any water on the water pump but have had drips coming from right below it. Most of the time it is the back side that is wet (around and below the oil pressure sensor).

What might be leaking and why is it only doing it now and then? Interestingly I have noticed that it leaks worse when there is a low pressure system in the area. Could it be somehow weather related?

There are onley a few places the water could be comeing from (Hoses,water pump,thirmistat houseing).Im thinking,it's either the water pump bearing or the water pump gasket.Because the problem is intermitant,it may have something to do with the out side temperature,causeing the the internal engine pressure to fluctuate.

I think you have a good description of a failing water pump. I would guess that the shaft seal is failing and the coolant is leaking from the weep hole. On the V6 pump it is located just under the pump shaft at the 6 o-clock position. Very hard to check visually since there is the pump hub and pulley assembly in front of the weep hole. Might be able to check with a small mirror when leaking. (Use Caution if Engine Running) I would expect the leak should get worse with time.

One thing you may want to try, run the car until warm, then park it and shut off the engine. With the engine warm and no cooling through the radiator, the cooling system pressure will peak and you may see a leak. (If looking from below, Use some Eye Protection)

Do you know haw many miles since the water pump was last replaced?

[This message has been edited by StockGT (edited 09-28-2007).]

quote Originally posted by StockGT: Do you know haw many miles since the water pump was last replaced?

It's from the factory I'm sure.

Your idea of the weephole leak is a good one except I don't see any fluids anywhere near that pully. Almost all the fluids are forward in the engine bay from there. I have tried heating up the engine and watching for the leak but it will not leak untill the car cools down. I was thinking maybe a gaskit leak.

Just because you don't see it doesn't mean it isn't happening. The water pump will leak a little from the weap hole for a while before the water pump finally completely fails. mine leaked over days. If it was me, I'd plan on getting the water pump replaced ASAP. If / when it fails, you'll quickly overheat and be stranded where ever you are. The worst part is that overheating might wreck other things, like headgasket, catalytic convertor, hoses, etc. The original factory water pump normally fails at less than 100k miles ((70k to 90k).

[This message has been edited by PaulJK (edited 09-28-2007).]

If you have a blown head gasket,the oil would be a milkey brown and the car would over heat.I agree with "StockGT",check for water dripping from the weap hole.But being that the water seems to be comeing from the farward part of the engine bay.That would be a 3 ft.pipe thats angled down (from the thirmistat houseing) twards the drivers side coolant tube,it is attached on both ends,with a ruber hose.The water may be traveling down this pipe and dripping off half way down.Check the hose at the thirmistat and wear it attaches to the 3 ft pipe, your probubly going to have to jack and crawl under the car with a flash light and inspect the 3 foot coolant pipe,most likely it's a hose attached to the pipe.