maxgee

iTrader: (5)

I can no longer use my stock overflow coolant tank b/c of my current set up. I assumed the coolant overflow tank only caught the extra coolant when the vehicle got up to operating temperature. Can anyone confirm? Or does the overflow allow coolant to return to the radiator when all is cooled?

intense3123

Yes coolant does return to the radiator from the tank. When you reach too much pressure, the cap's spring raises letting fluid into the tank. When the radiator cools down enough there's a vacuum created pulling the coolant back into the radiator.

You could run it without a tank, back like they did in the 70's. You just need the check the level more often.