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Leaking coolant from overflow tank

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Old Apr 2, 2011 | 07:09 PM
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Default Leaking coolant from overflow tank

My car is leaking coolant from overflow tank, it's not overheating and it's not overfilled. Suggestions?
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Old Apr 2, 2011 | 07:11 PM
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Originally Posted by mcalus
My car is leaking coolant from overflow tank, it's not overheating and it's not overfilled. Suggestions?
First thing....go buy a new cap. Yours could just be worn out.

After that, you need to see why air is being pushed (or sucked) into your coolant system, which usually means blown head gasket. A simple pressure test of the coolant system can tell you that.

.
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Old Apr 2, 2011 | 07:20 PM
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Why do u think air is getting in? Also I don't have any oil in coolant or vica versa
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Old Apr 2, 2011 | 07:25 PM
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Originally Posted by mcalus
Why do u think air is getting in? Also I don't have any oil in coolant or vica versa
The only way coolant can blow out through the over flow tank is because its either not holding pressure when it gets up to normal operating temp...because you have a bad cap.

OR...you have a blown head gasket and the associated piston is pushing air into the cooling system on the compression stroke.

OR........you have a very slow leak or a pinhole leak that is pissing coolant out while you're driving......then when the engine is shut down and cools, air gets sucked in through that small leak. Then after so long, as that air space grows in the cooling system....it can no longer stay cool while your engine is running and the overpressure gets pushed out through the cap and goes into the over flow tank.

Try a new cap.

.
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Old Apr 2, 2011 | 07:49 PM
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Okay I'll get a new cap tomorrow and report back, thanks for the help
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Old Apr 2, 2011 | 09:02 PM
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Put a new cap on, stopped leaking but it's running a bit warm, between 210 and the next mark ( toward hot )
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Old Apr 3, 2011 | 04:42 PM
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Topped off the coolant this morning before I drove it anywhere. Didn't overheat or leak! Thanks again
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Old Apr 5, 2011 | 02:53 PM
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Good to hear..............

.
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Old Apr 7, 2011 | 05:19 AM
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Anyone else have a problem with their overfill tank leaking at the seams. I've gone through about 4 of them, whats worse is that it leaks onto the alternator... but somehow my alternator still works..
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Old Apr 7, 2011 | 04:23 PM
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Originally Posted by hybenz
Anyone else have a problem with their overfill tank leaking at the seams. I've gone through about 4 of them, whats worse is that it leaks onto the alternator... but somehow my alternator still works..
F-Body????

The alternator is on the other side of the front end than the overflow tank.....no way water/coolant can leak onto the alternator if the tank leaks.

And alternators are immune to water....doesn't matter if they get wet.

.
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Old Apr 7, 2011 | 08:56 PM
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overfill tank is on the passenger side underneath the battery tray. like LS6427 says!
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