Steps for Replacing Brake Fluid in a Car
2 Answers
Below are the steps for replacing brake fluid in a car: Place the vehicle on a pit or lift it using a jack. One person should be under the car, remove the rubber dust cap from the bleeder valve, attach a transparent hose to the bleeder valve and a waste fluid collection bottle, then use a wrench to loosen the bleeder valve screw counterclockwise. Meanwhile, someone in the car should repeatedly press the brake pedal. At this point, brake fluid will spray out from the bleeder valve. Pay attention to the fluid level in the brake fluid reservoir and add new brake fluid as the level drops. Once the fluid runs clear, tighten the bleeder valve screw. The person in the car should repeatedly press the brake pedal to its highest point and hold it down without releasing. The person under the car should loosen the bleeder valve screw, wait until the brake fluid is completely expelled, then tighten the screw and notify the person in the car to release the pedal. Repeat this process several times until no air bubbles are visible in the expelled brake fluid. Monitor the fluid level in the brake fluid reservoir and add new brake fluid as the level drops to prevent air from entering the brake system. Repeat steps 1 to 3 for each wheel until all the brake fluid has been replaced.
As a car DIY enthusiast, I've changed brake fluid several times. The basic steps are as follows: Park in a well-ventilated area and begin after the engine cools down. Prepare new automotive brake fluid (such as DOT4), a small wrench, a container, cleaning cloth, and gloves. Open the engine hood, loosen the reservoir cap, use a suction tube to remove all old fluid, then fill with new fluid to the MAX line. The critical part is servicing each wheel: one person sits in the driver's seat to pump the brake pedal on command, while another loosens the bleeder screw at each wheel to drain fluid until fresh fluid appears, then tightens it - proceed wheel by wheel. Finally, check the fluid level, secure the cap, and test brake pedal firmness. Important reminder: Brake fluid is highly hygroscopic - over time its boiling point decreases, potentially causing brake failure, so change it every two years; improper operation introducing air can be dangerous, so beginners should seek professional help for safety.
