Ensuring your car has a smoothly functioning braking system is an important safety measure, and one part of it that often gets missed is the brake booster check valve.
One of the most critical parts to accomplish this is a little component that certifies there is indeed enough vacuum for brake booster assist in braking.
A failed check valve may result in a hard brake pedal and diminished braking ability. In this article, you will learn how to test brake booster check valve, and that too in an extensive way.
Topic Summary
Function of A Brake Booster Check Valve
The brake booster, or vacuum servo, what it is, and why we have been using them for so long. Its main purpose is to multiply the force of braking actuated by the driver via a pedal so that they may slow down or stop with less pressure. Modern vehicles are heavier and require more braking force as well.
For the internal combustion engine, work that allows sucking vacuum from hoses provides connection of brake booster. The brake booster will use this little vacuum to create a pressure differential inside its chambers when the driver steps on the under brake pedal.
The master cylinder multiplies the force applied to the pedal, and this amplified force is then transferred onto each wheel. The brake fluid is then pushed by the master cylinder through the machine of brake lines, applying each and every wheel’s brakes.
The brake booster is there to reduce the amount of manual force necessary during braking, which not only makes driving more comfortable but also shortens reaction times in accidents.
If the brake booster was not working, objects would need to be forced on a greater scale for braking, and that could mean longer stopping times, so risky driving may occur.
Symptoms of A Bad Brake Booster Check Valve
Signs of a bad brake booster check valve:
Hard Brake Pedal
The most obvious sign that your brake shoes may need to be replaced is if the pedal feels stiff or difficult. If the valve is faulty, then there will be a loss of vacuum and only minimal boost assistance for braking as required by the brake booster.
Increased Stopping Distance
If the check valve fails, air leaks into the brake booster, making it difficult to create enough braking power, leading to long stopping distances.
Hissing Noise When Press on the Brake Pedal
This could indicate a vacuum leak due to damage or problems with the check valve.
Engine Troubles
A check valve can fail, resulting in vacuum leaks that affect how the engine performs and possibly cause stalling or rough idling during braking.
Inspection
You can also check the operation of the read valve by blowing air through it. The idea is that air flows in a specific direction. When air flows both ways, when one sucks and blows at the other end, the valve is wetted up… hence it marks for the replacement of defective valves…
How To Test Brake Booster Check Valve
Tools and Materials Needed to test brake booster check valve:
- Vacuum pump or gauge
- Pliers
- Flathead and Phillips screwdrivers
- New check valve (if required)
- Clean rags
- Safety gloves and glasses
1. Find Out the Brake Booster Check Valve
The brake booster check valve is located on the brake booster, and it should be somewhere near the firewall of your engine compartment toward the driver’s side. A check valve is installed in the vacuum hose.
2. Look at the Vacuum Hose
Before you test the check valve, visually inspect the vacuum hose for wear and tear, such as cracks or damage to it. Brake booster problems can even be caused by the simple wear/tear of this hose, as it will create a vacuum leak. Change the hose if it needs to be
3. Remove the Check Valve
Pull the vacuum hose from the check valve with pliers. Place the check valve aside with your brake booster. Just one tip: Please be gentle so as not to break anything.
4. Take a Simple Blow Test
You can run a brief basic test on this by simply blowing into the check valve. And then you suck the valve through and blow this end, which is like a hose. Air should pass through. Now, blow from the other side. When blowing air past the opposite side does not come through, your check valve is broken and needs to be replaced.
5. Experiment with an Applicable Vacuum Pump.
For something as accurate and sensitive as this should be done with a vacuum pump or gauge,
- Connect a vacuum pump to the other side of that check valve on what line with a hose.
- Suck pressure by means of the vacuum pump. The valve should not allow the vacuum to go out.
- Depress the vacuum and put your finger over the opposite valve part. This site should never have any vacuum.
6. Interpret the Results
Determine Pass: The check valve is good if it lets air pass in one direction and holds the vacuum without leaking in the other.
Determine Failure: If the valve passes air in both directions or fails to maintain a vacuum, replace it.
7. Fit New Check Valve
If the check valve functions properly, reconnect it to the brake booster and vacuum hose. Change Check Valve Only if Defective
- Place the new check valve into the brake booster.
- Then, reconnect the vacuum hose tightly.
8. Test the Brakes
Reinstall the check valve and pull it away from your stop, then put some load on it. With the service brakes applied, you should see less than 15 minutes. It should be relatively firm and responsive to the touch. If the car does not stop as it should, then something is wrong such as a failed brake booster or vacuum system.
Also read: How To Repair ABS Module
FAQs About How To Test Brake Booster Check Valve
What are the symptoms of a failing brake booster?
Some of the most common symptoms of a failing brake booster are a hard pedal, much longer stopping distances, and engine stumbling or running poorly under braking. If you experience any of these issues, then it may be time to have your brake system evaluated.
How Does A Brake Booster Work?
When the brake pedal is pushed, a brake booster applies vacuum pressure from the engine to produce a difference in pressure among its chambers. The greater the difference in pressure, the more force from driver input is multiplied to press that pedal, meaning easier brake application and effective slowing or stopping of a vehicle.
Is It Safe To Drive The Car With A Faulty Brake Booster?
We don’t recommend driving a car with a bad brake booster. If the brake booster fails, this can result in a harder-than-normal brake pedal and longer stopping distances. This increases the risk of an accident because more force is required to bring your vehicle to a stop in emergencies. If you experience any issues with your brakes, always make sure to address them immediately for your safety and that of others on the road.
How to examine my brake booster check valve?
You can perform a simple blow test or use a vacuum pump to check the brake booster valve. Breathe through the valve, but make sure it is in only one direction. You can also use a vacuum pump to pull on the valve and make sure it does not leak. The valve must be replaced if air passes in both directions or it doesn’t hold a vacuum.
How often should the brake booster be serviced or replaced?
Most brake boosters are maintenance-free and should last the life of the vehicle. But you can try keeping an eye on them by checking every time after a hard brake for marks. Checking the brake fluid and inspecting brake lines during routine maintenance can help keep your setup working, but when a booster goes bad or you get an ABS warning light on top of braking issues, it may be time for a Mercedes intake step and repair.
Conclusion
It is important to check the brake booster check valve and test it regularly so that you drive safely on the road. This way, you can be certain that your braking system always works in the best conditions. Make sure to consult your Vehicle’s manual about procedures regarding what parts of the car and get professional help if needed.