Brake bleeding is an essential maintenance routine that has to be done many times throughout the lifespan of your car. This repair job is done when you start feeling your brake pedal getting soft, and you notice a reduction in the stopping power and time. But when you don’t have time to get your car to the mechanic, you can’t help but wonder if brakes can bleed themselves.
So, can brakes bleed themselves? No, they cannot. You have five options if you want to get your brakes functioning as they should. You can opt for any of these manual methods, but the brakes won’t bleed themselves without you taking any action.
The five methods for bleeding brakes are:
- Gravity bleeding
- Pedal and hold
- Pressure-operated venturi
- Vacuum pulled
- Pressure tank
In this article, you’re going to learn the importance of bleeding your brakes and how to do it.
Can Brakes Bleed Themselves?
Your vehicle’s brake system needs to be bled once every two to three years to maintain optimal performance. But why is this necessary? As you drive your car, small volumes of air get trapped in your braking system.
The air may also sneak into your braking system during routine maintenance and service. Another cause for air to get into your braking system is a leakage in the system. And if your brakes are worn out, air will have an easier time accumulating in the system.
When this happens, you start experiencing a spongy feel when you place your foot on the pedal. In some cases, the air inside the brake system may even delay your braking time and speed, which can be dangerous.
To fix the problem, mechanics remove all the trapped air from the brakes. Sometimes, they fully replace the brake fluid to ensure everything is in tip-top condition – a type of extended brake bleeding process.
5 Methods for Bleeding Brakes
As you have read, bleeding your brakes should be among your priorities when you think about regular maintenance practices for your car. It may seem like lots of work, especially when you have a busy schedule, but it’s a task you can’t afford to ignore. Driving around with compromised brakes could cost you your life.
Below are some of the common methods of bleeding brakes. No matter which method you decide to go for, the preparation is the same.
- Soak the bleed screws in penetrating oil.
- Siphon the rotten curd out of the reservoir.
- Add clean brake fluid.
Remember to start with the bleed screw that’s located the furthest from the master cylinder and work up to the closest one.
Note: Brake fluid is poisonous and can destroy paint. Therefore, be cautious when using it. Wear protective clothing and cover any exposed areas of your vehicles. It’s also advisable to have a bucket of cool water in sight to flush out any spills if they occur.
1. Gravity Bleeding
If you want to bleed your brakes on your own or you don’t have someone to assist you, gravity bleeding is a simple one-person job. To begin, attach the hose to the bleed screw, open it up, and wait for the brake fluid and air to flow out of the system.
In most cases, a small bottle is used for gravity bleeding. However, it doesn’t hold much brake fluid, so this is something to keep in mind. Nevertheless, smaller bottles are preferable because they help you avoid the risk of draining the reservoir dry.
You should also keep an eye on flow changes while gravity bleeding. One minute the bottle may be empty, and the next minute it is overflowing. This can be caused by sudden flow changes or time dilation.
The following video shows you show to gravity bleed your brakes on your own:
2. Pedal and Hold
Sometimes, gravity bleeding may not cut it. In such cases, the pedal and hold method is an excellent alternative. For this method to work, you’ll need assistance. One person will be inside the car pumping the brakes, and the other will crack open and close the bleed screws.
For this method to work, you need to establish callouts and procedures ahead of time.
3. Pressure-Operated Venturi
This method uses compressed air and a venture to draw the brake fluid and air out of the bleed screw. The air and fluid are drawn out of the system and flow quickly into the hose. However, while it’s an effective way of bleeding your brakes, it creates large bubbles in the system, which can be a bit challenging to work around.
4. Vacuum Pulled
This method is similar to the venture procedure. The only difference is that you’ll be using a handheld vacuum gun. Just like the venture method, you’ll have to deal with air getting inside the bleed screw threads and creating a tube full of bubbles.
However, according to Hagerty, slathering some heavy bearing grease around the bleed screw can help you stop the bubbling.
The method is simple. Hook up the bleed screw adapter, hoses, and catch container. Next, create a vacuum and crack open the bleed screw.
5. Pressure Tank
The pressure tank method is the best brake bleeding method there is. In cases where you want to get all the contaminated brake fluid and air out of the system, you should choose this method.
The procedure is quite simple. Begin by analyzing the tank-to-master-cylinder connection for leaks with air only. Next, go around the car cracking open bleed screws using a wrench and ensure you have a catch can in hand.
Why Should You Bleed Your Brakes?
Hydraulic brakes require bleeding for two reasons. One, you need to do it to remove air bubbles from the brake system. Two, brake bleeding is important for replacing old brake fluid with new fluid.
Air Removal
For a hydraulic system to function effectively, it has to rely on a compressible fluid as a means of transferring forces. In a hydraulic braking system, when you operate the brake lever, the input forces travel via the brake fluid to run the caliper pistons which then move the brake pads, causing them to come into contact with the rotor.
This functioning of the braking system is only possible because the brake fluid is incompressible. Think of it as a type of communication. The brake fluid sends the message it gets from the lever to the caliper without any loss in quality.
When air is introduced to the system, this communication is interrupted. The input forces created by operating the brake lever are no longer effectively transmitted because the air inside is compressible. As a result, all the input forces go to waste, and your brakes may stop functioning entirely if the situation gets worse.
Brake Fluid Replacement
The other reason why it’s important to bleed your brakes is to change the brake fluid. Over time, the brake fluid collects contaminants like dust, air, and water from the environment.
When you replace the brake fluid occasionally, it keeps the contaminants at a minimum, thereby ensuring your brake system stays and functions perfectly. But bleeding your brakes and fully replacing old brake fluid with new brake fluid removes all contaminants.
Time to Bleed Your Brakes!
Can brakes bleed themselves? Don’t count on it. You’re safer bleeding the brakes manually. Fortunately, there are a variety of ways to do it. Consider the options provided in this article and bleed your brakes. And if DIYs are not your thing, there’s no shame in seeking professional assistance. It may cost you, but you can rest assured that your brakes will be bled properly.
