How to Replace a Brake Vacuum Check Valve
Vacuum check valves are used in different vacuum systems of a vehicle such as the EGR, braking system, air conditioning system, and the intake manifold. If any of these systems are acting up, a leaky or malfunctioning vacuum check valve could actually be the culprit. The problem is that tracing a leak from possibly half a dozen small leaks can be a very difficult task. With the right tool, though, you'll surely succeed over the challenge and be able to install the new vacuum check valve needed by different systems, respectively. Here's how you do it with the brakes:
Difficulty level: Moderate
What you'll need:
- Hand-held vacuum
- New brake check valve
Step 1: The first thing that you should do is to make sure that the engine has completely cooled down. You don't want to get hurt while working with your car, right?
Step 2: Next is locate the check valve in your braking system. Find the area in your engine where the latter connects to vacuum booster, because the brake check valve is often mounted in that location. But a quicker way to do that is to look for a vacuum line.
Step 3: Vacuum lines are often securely held into place by clamps. You need to have these clamps taken out in order to free the vacuum line. The vacuum line can accidentally be damaged while removing all of the clamps, so you have to be extra careful. If not, you surely won't be able to finish the job because you'll have to head to an auto car part dealer for a replacement of the vacuum line that you are supposed to still use at the end of the process.
Step 4: Upon removal of the vacuum line, you can now reach the brake check valve so as to easily remove it. The valve has some screws around it that needs to be undone with the aid of a screwdriver. Ready a wrench as well in order to loosen the valve. After doing so, pull the valve out in order to determine whether it is faulty or not.
Step 5: Using a hand-held vacuum pump, apply pressure into the input end of the valve. Check the pressure if it reads between 15 to 20 hg. Notice if the pump shows that the valve is losing pressure. If it does, you will have to install new check valve because the existing one is leaking.
Step 6: It is now time to install the new check valve for your brakes. Mount it right to the place where you took it out earlier. To make sure it is secured, use a wrench to tighten the valve. The screws should also fit flush. After that, reattach the vacuum line, and ensure that its clamps are tight enough.
Step 7: After successfully installing the new vacuum check valve, try the braking performance and determine if the leak has been remedied already. If the brake pressure is still not satisfying, that you can obviously feel that its power has gone weaker, you'll have to trace the problem by starting on a different part of the assembly, which is the vacuum booster perhaps.