Stant is the nation’s leading developer and manufacturer of automotive radiator caps. Stant offers a wide variety of radiator cap styles and applications for U.S. and import cars, light trucks, HD trucks, racing, off-road and ag equipment, such as the Stant LEV-R-VENT® radiator caps. They fit in the smaller spaces of today's engines, while providing a pressure release lever and may fit on applications where older, larger-shell caps may not. A tab on the bottom of the lever interlocks with the filler neck to prevent removal of the cap until the lever is lifted. When the lever is lifted, the entire pressure valve is lifted off the lower sealing seat in the filler neck, harmlessly venting pressure through the overflow tube.
The radiator pressure cap has a fivefold job:
Filler cap to access the cooling system
Closure cap to keep coolant in the radiator
Pressure cap to prevent
overheating by pressurizing the system
to raise the boiling temperature of coolant and allow the automobile's engine
to operate at more efficient higher temperatures
Pressure relief valve to safely
and harmlessly vent excess pressure
into the overflow jug
Vacuum relief/siphon valve to
draw coolant from the overflow jug back
into the radiator to prevent air from entering the system and allowing the coolant
to perform its function more efficiently.