SYSTEMS
THERMOSTAT
RADIATORRADIATOR CAP
The radiator cap is used to build limited pressure in the cooling system. This increased pressure raises the effective boiling point of the coolant to permit absorption of more heat. However, a pressure relief valve in the cap releases pressure so the radiator and hoses do not explode. The cap also provides vacuum relief when the coolant cools and contracts; otherwise, the radiator would collapse.
SYSTEMS THERMOSTAT RADIATOR