Radium Engineering Universal Coolant Expansion TankCoolant expansion tanks are necessary for proper air bleeding in applications that utilize a low mounted radiator (such as a V Mount) or rear mounted radiator. However, expansion tanks are also valuable if integrated in a common radiator setup. To allow heat expansion, traditional coolant systems require air to be present in the top portion of the radiator during low temperatures. An coolant expansion tank permits the radiator to be 100% filled with