Pettit AST.
 

This Pettit AST came with the car when i bought it, However recently i think i'm having some problems with the cap that came with it. Every time i drive it for a while and i park it to go to the store, I come out and i see a little antifreeze under the car. I open up the hood and i see that there is trail of antifreeze on the sides of AST. So i think that there might be problem with the Cap.

It says on it 13lbs so i don't know if this is the one that came with AST or someone else bought it. If anyone has one, can you please tell me if you had problems with the cap if not how much lbs can your handle? Thanks a lot

I have a 13 lb cap on my Pettit AST and its working fine. You can go to any auto parts store and buy a new one. They're generic caps.

do they ever go bad or something? Could the cap be foulty then?

buy a 16PSI cap and it will resolve your problem.

i have the pettit ast too, and havent had a problem with it. they say its good to replace those caps every once in a while though.

The correct cap is 13 psi (0.9 bar). Yes, they do go bad, so go get a new one, they're not very expensive.

Boostin, Also check the top of the filler neck on your AST. When I bought my car the Pettit had two 'dings' in the top where it is supposed to seal on the cap. I had to dress them out with some emery. It was not drawing the coolant back into the system. Good luck, Tom

I have a Pettit AST and mine came with a cap. We pressure tested the cap and it didn't release the pressure when it said it was supposed to (I think it was 13 psi). I went to several auto parts stores in the area and every one of them that I tested didn't release when they said they would. I checked at Advance Auto, Autozone, and several other places. I finally went to NAPA and their cap tested perfect the first time. So if I were you I would find a friend with a pressure tester for radiator caps (I know that Snap-On tools carries them) and test your cap. It is probably bad. If it is bad then I would suggest you take the tester with you and go to the nearest NAPA store and get a new one ASAP.

That should work for you, but you obivously want to look for indentifiable leaks in the AST

I bought a replacement cap with 13psi at the Autozone. I drove it really hard today and after idling for 3 minutes i shut it off and it didn't leak or anything. So I think i fixed it with this cap then. Thanks to all of you who replied.

Cool

Much Cool

Like others have said, those caps go bad every once in awhile. When you shut off the car, the cooling system isnt fully pressurized, and it vents the coolant into the overfill tank, and then it overflows out of that. Something like that. 16lbs is pretty harsh for street driving though, I'd stick with the 13lbs.