Stant® 10258 - Engine Coolant Reservoir Cap

The radiator cap does far more than just cover the opening in the radiator. On modern vehicles the radiator cap pressurizes the cooling system to raise the boiling point of the coolant. The cap allows excess coolant to flow to the coolant expansion tank when the engine is hot, and back into the radiator when the engine cools. The cap should be inspected and tested every time the cooling system is serviced. Check the cap seals for cracks and other signs of damage, and pressure test the cap with a cooling system tester. A defective cap will not be able to maintain its rated pressure, allow the coolant to boil and cause the engine to overheat. A faulty cap may also not allow coolant to transfer back and forth between the expansion tank and the radiator.

When you need a new radiator cap, you can’t do better than a Stant. Stant is the world leader in the design and manufacture of cooling system components for the automotive aftermarket. The company offers an extensive range of cap styles for domestic and imported cars, light trucks, heavy-duty trucks, racing, off-road, and agricultural equipment.

Stant standard original equipment type caps have a SWIV-EL design that makes removal and installation easier. They’re made from premium materials, meet all original equipment specifications, and are designed for use on open cooling systems and overflow reservoir type systems. The patented Lev-R-Vent radiator cap features a lever that allows pressure to safely be released before the cap is removed, to prevent injury. The Lev-R-Vent cap is also made from premium materials, meets all original equipment specifications, and is designed for use on open cooling systems and overflow reservoir type systems.

Stant has an extensive line of high and low pressure racing radiator caps specially designed to meet the extreme demands of racing engines. Low pressure caps are made from higher quality materials and to closer tolerances than standard caps and are available in 13 or 16 pound ratings. High pressure caps are available for open and closed cooling systems in pressure ratings from 19-32 pounds. Stant vented radiator caps have a small disc at the bottom of the cap that is a vacuum valve. The vacuum valve hangs down in the open position until the cap is exposed to the rapid expansion of coolant or steam, which closes the valve in the sealed position. This pressurizes the system, helps control overheating, and enhances cooling system efficiency.