does anyone know y? doesnt overheat..had no problems..

 

Maybe the cap on the radiator is faulty and is allowing the pressurizing antifreeze to escape into the overflow tank then out the top .

 

I can try a new cap,,it seems to do it worse when the resivor is full like it should be..Thanks

 

How full do you fill the overflow tank? If you overfill & or fill it plumb to the top, it will overflow.

 

its sounding like a head gasket is on its way out. cooling systems run 15psi max, if you have the samllest leak from the cumbuston chamber to the water jackets in the block then your pressureizing the cooling system to maybe 50-150psi, which the cap will regulate the pressure and dump the excess in the overflow bottle. the leak may not be big enough yet to cause a overheating concern, but it could evuentually.

 

I only fill it to the full-hot line..and that sucks if it's a head gasket going..thanks for the info..

 

Hated to ask that question, but there be some that thinks your to fill the radiator overflow plumb full. If that was the problem it sure would be much easier that a head gasket or something worse. Sorry to say its kind of sounding like a head gasket or worse.