Pressure build up in my cooling system

Hello guys,

Ive got some isssues. Just noticed this issue starting today. I bought a guys project engine a year ago. The engine was rebuilt by one of the local machine shops in his town. I have reciepts. Anyway the engine has sat awhile almost 2years completely assembled. The engine was never started. I installed this engine in my Dart [318] and it fired right up. The head gaskets started to weep water on the back corner. One corner on each head. I put some sealer in radiator and have seen no further leaks from the gaskets. I just got the car back from the paint shop and have had time to run it for extended periods of time. Now this is where it gets interesting. When I first start it cold after about 1-2 minutes the radiator hoses are hard [pressurized] way to hard for a cold start. After I relieve the pressure and warm it up with the cap off it does not do this senario. I can put the cap on and take it off without to much pressure. I think the combustion is pressurizing the coolant system when its cold. Its like the head gaskets are not sealing until it is hot. Should I re-torque the heads? Is this required on this engine? Should I just take the heads off and install new gaskets? No oil and water appear to be mixing. Radiator, t-stat,heater core,hoses,water pump are all new. Any help would be appreciated. Normally a head gasket is bad or good. If you pull the cap off when it is cold and start it no coolant shoots out the filler neck.
Author: admin