Ok, so I had a new radiator installed a year ago, water pump is about 3 years old but still good, as well as the stat. I first had a small pin hole leak in the stat gasket which i replaced and fixed, though now, i had the hood up and the jeep running for a few minutes when I noticed why I was still having to add coolant every so often. My radiator cap is leaking when under pressure. It's almost like when the pressure is reaching that 16psi mark, the pressure releases but instead of tansfering to the overflow, it's almost like the seal on the top of the cap isn't doing it's job. Yes the neck of the radiator is plastic and the overflow transfer hose is not stopped up. I guess I need to buy a new cap but in everyone's experience, is that going to resolve the issue. I've heard before that people have still had problems with it leaking even after a new cap.

 

You must replace your radiator cap. They are only about $5.00. Buy one.

Do not buy one with a pressure release lever. It is not necessary and it provides another point for the cap to fail.

You want a 16 pound cap. Stant is a great brand.

 

have the cap pressure checked if no good gety a new one

 

If it still leaks after replacing the cap, check the neck of the rad for crack/bad sealing surface.