How to Bleed the Brake System After Adding Brake Fluid?
2 Answers
The steps for bleeding the brake system after adding brake fluid are as follows: 1. The bleeding operation requires two people to cooperate. After replacing or topping up the brake fluid, the air in the hydraulic lines should be bled. 2. One person sits in the driver's seat and repeatedly presses the brake pedal to raise its position, then holds the pedal steady without releasing it. Meanwhile, another person underneath the vehicle loosens the bleeder valve to allow air and brake fluid to escape from the lines. When the pedal position drops, immediately tighten the bleeder valve. 3. Repeat this process several times until no air bubbles are seen escaping from the plastic tube. Tighten the bleeder valve and reinstall the dust cap. Follow the above method to bleed the other wheel cylinders in sequence. During the bleeding process, continuously check and top up the brake fluid until all air is completely expelled. Then, add an adequate amount of the specified type of brake fluid to the reservoir.
Last time I changed my car's brake fluid myself, bleeding the system was crucial. Remember to find a helper—you sit in the driver's seat while they operate at the brake caliper. Start the engine and pump the brakes a few times to build pressure. Begin with the wheel farthest from the master cylinder, like the right rear, and loosen the bleeder valve. Then, have your friend press the brake pedal repeatedly while you watch for fluid flowing from the hose—make sure it goes into the bottle without air bubbles. After a few pumps, the bubbles will disappear, and the fluid will run clear. Tighten the valve immediately. Don’t forget to check the master cylinder fluid level to ensure it doesn’t drop too low, topping it up with fresh fluid as needed. After finishing, test the brake firmness to ensure safety. The process is simple but requires attention to detail—if air isn’t bled properly, the brakes will feel spongy, which is dangerous while driving. I recommend buying a dedicated tool to make the job easier.
