steaming pipes
Sounds like a possiable cracked head, as it gets worse as it gets hotter. But when does this happen? Is it within 5 min. of crank up or after the engine has warmed up? If it's within the 5 min. it normal condensation, but if it's after the engine is warmed up then it's more than likely a cracked head. But then you would think that the radiator would show signs of useage unless it's very small.