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Radiator Cap

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Radiator Cap Products

A radiator cap is more than your average cap. It is designed to raise the temperature of the engine coolant and at the same time maintain and control the pressure within the cooling system by releasing the built up pressure at the right time. The radiator cap also prevents the coolant from boiling beyond capacity once the temperature is too high. The other function of the radiator cap is set into action once the vehicle comes to a halt, wherein the coolant's temperature drops to normal resulting to a sudden surge of negative pressure within the cooling system. The cap vents allow the atmospheric pressure to enter and in the process, neutralize the negative pressure within the cooling system. Damaged or defective radiator caps are one of the causes why vehicles overheat. that's why you have to make sure that you replace your vehicle's radiator cap the soonest possible time to avoid further cooling system problems. There are different types of radiator caps designed to handle various pressure levels. You should purchase the exact replacement radiator cap for the type and make of vehicle that you have. Regardless of your radiator cap requirement, you may check our online catalog to see and choose from the selections that we have. If you need help in selecting the radiator cap for your vehicle, you can always contact our 24/7 technical support to assist you. Call us now!

Repair Guides

Date Published :

How to Troubleshoot and Fix Your Leaking Radiator Cap

Your car’s temperature control system is able to work efficiently with the help of pressure. Pressure is safely contained in your radiator, thanks to a spring-loaded cap. Overtime, extreme heat and pressure will take its toll on your radiator cap and cause it to wear and get damaged. If the problem is left unchecked, your cap may start to cause a coolant leak, which can eventually lead to engine overheating. Overheating is perhaps every car driver’s worst nightmare; so, to prevent this from happening to you, make sure you address your faulty radiator cap right away. Below are some basic steps that you can follow to easily replace the busted cap in your system.

Difficulty Level: Moderate

Things you’ll need:

  • Gloves
  • Hand towel
  • Coolant system pressure tester
  • Replacement radiator cap

Tips and Warnings:

  • Never conduct a test to see if your radiator cap is busted when the engine is hot. This can cause you some serious burns.
  • For the best results, we recommend that you use an OEM part for your repairs. This will ensure excellent fit and easy installation.

Step 1: Open your hood and put a towel on top of the radiator cap. Start removing the cap by pushing it down and twisting it to the left (counterclockwise).

Step 2: After that, get the pressure tester and screw the cap adapter on it. Once you’ve secured their connection, attach your radiator cap at the other end of the adapter.

Step 3: Next, start running the tester by pumping its handle. Do this until the tester’s gauge registers 15 lbs.

Step 4: Once you’ve stopped pumping, watch the gauge and see if the number starts to drop. If it does, this means you have a busted radiator cap.

Step 5: Throw your old cap and get its replacement. Attach and secure it in place by turning it to the right (clockwise).

Step 6: After tightening it, keep the hood open and start your engine. Check your new cap for any bubbling or discharge while keeping a safe distance from your radiator.

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