The extreme heat and pressure of a radiator can cause wear and tear to the radiator cap. Radiator caps should be replaced once a year to prevent problems with your cooling systems. Most radiator caps cost less than $10, making replacing the cap one of the least-expensive methods of preventative maintenance. Replacing a radiator cap is simple, but certain precautions must be taken to ensure your safety.
Turn off your engine and allow the vehicle to cool for at least 30 minutes. Engine coolant can reach temperatures of 200 degrees Fahrenheit or higher. Not letting the engine completely cool can cause dangerous burns.
Wear gloves and place a hand towel over the radiator cap. Slowly twist the cap counterclockwise without removing it. Wait a few minutes to let the pressure release from the cooling system.
Remove the old cap and discard it. Replace the cap with a new one and turn it clockwise, getting it as tight as you can.
Start the engine and keep the hood popped. Keep at a safe distance from the radiator and inspect the cap for discharge or bubbling around the edges.
