We designed this 6 x 4 x 2 frame mounted box style overflow tank for a customer short on space. A site glass is also available upon request.
Should the system pressure exceed the cap’s rating, the spring will compress and fluid will flow through the upper tube to fill the chamber.
In the event the recovery tank reaches ~1.6 pint capacity, the fluid will find the second tube and exit to the street. A vacuum will draw the coolant back into the cooling system as the engine cools down.