How to bleed car brakes properly

bleed car brakes

Bleeding the brakes yourself can be difficult and time consuming. You need a place to jack up your car. You should also be prepared to get very dirty. Therefore, most people leave the bleeding to the professionals who have the necessary equipment. However, if you want to bleed car brakes yourself, this guide will help you.

First you need a venting device. Such a device speeds up the work significantly and you don’t need anyone to help you. Bleeders operate by applying pressure to the bleed valve. This makes the liquid flow out more easily. You would normally need someone to sit in the car and press the brake pedal while catching the fluid on the wheel. The ventilation device makes this superfluous and you can carry out the ventilation alone, which is much faster.

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Why do you have to bleed car brakes?

As you probably know, the brake fluid wanted to be changed every 2 years because the brake fluid attracts moisture from the air. If the brake system is subjected to heavy loads from long and prolonged driving, it becomes hot and the heat is transferred from the brake pads to the brake pistons and from there to the brake fluid. The water content in the brake fluid begins to boil much earlier than the pure fluid would.

This process leads to vapor bubbles, which cause a longer pedal travel and a decreasing braking effect.
This happens because the water in the brake fluid is compressed in the brake lines. The driver can determine this very quickly, because the brake pedal feels very “spongy” at this point and can be pushed through without braking.

How do you bleed your brakes?

Step 1: First you have to jack up your car. Make sure that the car is secure before working on it. If you shake it lightly, you can see if it is firm. However, do not push too hard in the event that the car is not stable, as the jack could then slip and the car could be damaged.

Step 2: When the car has been lifted and is standing securely, you have to remove the wheels. Use the wrench for this.

Step 3: Now remove the cover of the brake fluid reservoir. If the brake fluid level is low, fill it up before bleeding the system.

Step 4: Start with the bleed valve that is farthest from the master cylinder. Then attach the hose to the valve.

Step 5: Carefully open the vent valve.

Step 6: Pump slowly and observe how the liquid flows evenly through the hose. You can close the screw when there are no more bubbles.

Step 7: Repeat this process for every other brake valve until all four are thoroughly vented. Make sure that the amount of brake fluid in the reservoir does not drop below the minimum, as this could cause air to enter the brake system.

Step 8: assemble the wheels and tighten the screws.

Step 9: Check if there is enough brake fluid left and refill if necessary. Screw the lid back onto the container.

Step 10: lower the car from the jack.

Step 11: test your brakes.

TIP: you can make a handy bleeding device from a plastic bottle and some hose.

Think about your safety!

Brake fluid is a dangerous chemical and should be handled with care. Therefore, you should definitely wear gloves when bleeding the brakes and wash your skin and clothes thoroughly if you have come into contact with the product. If you are dealing with brake fluid, always read the label first and follow the instructions carefully. If you have safety concerns, you should hire a workshop to bleed the brakes. 

If you bleed the brakes, it is important that you test them afterwards. If anything seems wrong or the brakes feel weaker than before, then you shouldn’t try to solve the problem yourself unless you are absolutely sure where the problem lies. Driving with broken brakes is extremely dangerous