Radiator Cap Pressure

If your coolant is leaking it could mean your radiator cap is bad if the cap isn t releasing excess pressure properly that pressure can force the coolant to leak out at the point of least.

Radiator cap pressure.

When the fluid pressure inside the radiator exceeds 15 psi it forces the valve open allowing heat to escape and excess coolant fluid to overflow into the tanks on either side of the radiator. The top portion of the radiator cap will list the pressure rating. The boiling point of water increases when the water is. The same way a pressure cooker increases the boiling temperature of water.

So the over simplified answer to the tech quiz is that yes a higher pressure radiator cap can help prevent overheating. The water heats up and boils and 212 degrees. Usually this is set at a density of 15 pounds per square inch psi. Radiator caps are critical to catch coolant overflow keeping your engine cooling system operating at optimal pressure and temperature and your vehicle operating at optimal performance.

The radiator cap acts as a release valve set to open at the maximum pressure point. Let s take a pan of water and heat it up. As the vacuum continues to build up the two way check valve which is exactly what a radiator pressure cap is goes to work. Gates manufactures our oe quality radiator caps and cool control caps for your heavy duty vehicle applications with a selection of durable wear resistant radiator caps for automotive applications without.

That same mix at 16 pounds per square inch psi of pressure boils at approximately 250 degrees. If there were not a radiator pressure cap installed the system would draw in air. We get asked this question daily and it seems most people misunderstand what the pressure cap does. The radiator cap actually increases the boiling point of your coolant by about 45 f 25 c.

And the boiling point increases 2 3 degrees for each additional psi of pressure in the system. If you do not have the equipment to do the radiator cap pressure testing you can have it done at a shop. The radiator cap releases the extra pressure by sending some coolant into the overflow tank. You have a coolant leak.

The cap is actually a pressure release valve and on cars it is usually set to 15 psi. Air causes poor engine cooling and is the main cause of cooling system component corrosion. You may find that it is beneficial to test the cap so that you can be sure that it is working properly. While you re in there check to make sure your coolant overflow tank is working properly.

The radiator cap allows pressure to build up in the cooling system and will eventually vent that pressure to the overflow bottle as the need arises. The cap pressure rating has nothing to do with regulating your engine coolant temperature nor will it make your engine run cooler. If you have a bad radiator cap the coolant could get released too quickly and cause the reservoir to overflow. How does this simple cap do this.

You ll notice that there s a plunger on the bottom of the cap.