How to Replace a Brake Check Valve

Lead Image
  • 1-3 hours
  • Beginner
  • 25-50
What You'll Need
Hand-held vacuum
New brake check valve

The brake check valve is an important part of the vacuum booster in a car engine. A vacuum booster is responsible for creating a vacuum pressure that can be used by the engine to boost the pressure that goes into a vehicle’s brakes. The brake check valve is used to regulate this vacuum pressure. When the valve malfunctions, the vacuum pressure being produced by the booster can not be effectively used to power the brakes.

In the case of a malfunction, the pressure going into the brakes is usually less than the brakes need. This can result in accidents as the brakes won’t be able to function to their full capability. Replacing the brake check valve can be a simple job if you have the right information.

Step 1 - Locate Brake Check Valve

Locate the brake check valve to start working on it. The brake check valve is usually located in the area of a car engine where the engine connects to the vacuum booster. This connection can be further identified by looking for a vacuum line. The brake check valve is located here.

Step 2 - Remove Clamps

Most vacuum lines have clamps holding them into place. Before you can remove the vacuum line to move on to the next step, you have to carefully remove all the clamps. Remove the clamps carefully and delicately to avoid any damage being caused to the vacuum line. You will be reattaching the same vacuum line at the end of the process.

Step 3 - Remove Brake Check Valve

After you have removed the vacuum line, you will have full access to the brake check valve. You can now easily remove the valve. Use a screwdriver to loosen the screws around the valve and a wrench to loosen the valve itself. Once you have done that, you can easily pull the valve out of its place. Then, use the hand-held vacuum pump to apply vacuum into the input end of the valve. The vacuum should be between 15 to 20" hg. If the pump shows a loss of vacuum, it means the valve is faulty.

Step 4 - Install New Brake Check Valve

Reversing the process that you went through to remove the old brake check valve, install the new brake check valve onto the booster mechanism. Tighten the valve with a wrench and the screws with a screwdriver. Once you have installed the new valve, reattach the vacuum line, reversing the process you used to detach it.

Step 5 - Check Brakes

After installation of the brake check valve is complete, start the engine and check the brakes. If the brake pressure and power still seems to be low, there might be a problem with the vacuum booster too.