oz
Founding Member
I just saw this but I wouldn't assume that a closed overflow tank would help out much. Once enough fluid entered the tank, the air pressure above the liquid would equal the cap pressure and pressure in the radiator (13 lbs) and any more pressure in the system would cause the cap to fail and steam. I have honestly never heard of a totally 'closed' system. Even new cars I have seen have a hole at the top for venting and overflow.
I am very surprised that the tank from Summit did not come with a vent already installed. I think it's important to have atmospheric pressure in the tank.
I think you've solved your problem.
I am very surprised that the tank from Summit did not come with a vent already installed. I think it's important to have atmospheric pressure in the tank.
I think you've solved your problem.