Car brake fluid is the blood of your vehicle’s braking system; without it and proper maintenance, the brakes could fail and the safety of yourself and others around you may be compromised. It is vital therefore to understand how to bleed brakes should the fluid need attention, explained below with our expertise knowledge at CarParts4Less. You can find everything you need to bleed your car brakes including brake fluid.
Why Do We Bleed Our Car Brakes?
Firstly though, why do we ‘bleed’ brake fluid? Bleeding brake fluid is the process of removing trapped air in the brake system, whilst also discarding some old fluid, therefore ‘bleeding’ the system. This is an essential process in car maintenance because as time passes, the fluid loses its moisture resistance and will begin to take on water, corroding your braking system’s parts.
How To Bleed Your Brakes
Your car’s brake fluid should be bled every 2-3 years and can be done from home with an extra pair of hands or a trained mechanic. Here is how to get your brake fluid in top condition:
Step 1 – Check Which Fluid You Need
It is important to first check which type of brake fluid your car requires. Like petrol and diesel, they do not mix well together, so check your vehicle’s manual or get a recommendation from a mechanic with your car details before beginning the bleeding process.
Step 2 – Jack Up The Vehicle
On your garage floor or driveway, use a jack to elevate your car and support it with 4 jack stands. As you will be underneath the vehicle on occasion, ensure it is safely suspended. Once this is done, remove all 4 of the wheels.
Step 3 – Loosen The Bleeder Screws
Locate the brake calipers underneath the vehicle (if it has 4 rotors, your vehicle will have 4 calipers. A car with 2 rotors and drums will have 2 calipers). Next, find the bleeder screw on the bottom of the caliper and use a box wrench to loosen the bolt gently. Don’t twist too hard. If the bolt won’t loosen, use penetrating oil and let it soak for 30 minutes. Attempt to loosen again.
Once loosened, place the screw back. Ensure each bleeder screw is securely placed back to avoid air bubbles building back in the brake system.
Step 4 – Check Brake Fluid Levels
The brake fluid reservoir should remain full whilst bleeding the brakes. To check this, lift the car hood and locate the reservoir in one of the back corners of the engine compartment. Open the cylinder cap and add extra fluid if the level is lower than the highest mark.
Step 5 – Attach Tubing To The Bleeder Screws
With some plastic tubing about a ¼ inch in diameter and starting with the brake furthest from the master cylinder, cover the screw and place the other end into a jar or disposable bottle of brake fluid. The fluid will prevent air from building back into the brake.
Step 6 – Engage The Brake Pedal
Make sure that the engine is not running whilst bleeding the brakes.
Your assistant should now take charge of the brake pedals. Ask them to pump the pedal a few times and then halfway to the floor. The pedal should not go all the way down yet.
Ask your partner to push the pedal down and call out once done.
Use your wrench to begin opening the bleeder screw. Old fluid and air will now drain into the container at the other end of your tubing.
Just as the pedal reaches the floor, your partner needs to call out “Down”. Immediately close the bleeder screw when they do.
Your partner will then lift up the pedal.
Repeat this several times until no more air bubbles are released with the fluid.
Continue with Steps 5 and 6 until all of the bleeder screws and brakes have been bled.
Step 7 – Check The Master Reservoir
Reinstall the wheels and lower the vehicle.
As your partner firmly presses the brake and releases, check the fluid in the master reservoir. If there is slight movement in the fluid, good job! Your work is done. However, if the fluid moves erratically, there are will some air bubbles in the system; the bleeding process will need repeating until the fluid settles.