What is the method for replacing car brake fluid?
2 Answers
The method for replacing car brake fluid is: 1. Open the car hood and locate the brake fluid reservoir; 2. Open the reservoir cap and use a syringe to extract all the brake fluid from the reservoir; 3. Add new brake fluid. The functions of brake fluid are: 1. Brake fluid has a very low freezing point, ensuring good fluidity at low temperatures; 2. Brake fluid has an extremely high boiling point, preventing vapor lock at high temperatures; 3. It does not cause corrosion to metal and rubber. Symptoms indicating the need for brake fluid replacement are: 1. The brake warning light alerts or flashes during emergency braking or continuous braking; 2. The braking distance becomes noticeably longer than before during emergency braking; 3. The brake pedal feels soft or weak when pressed; 4. The braking force feels inconsistent, varying between light and heavy during braking.
Speaking of changing brake fluid by myself, I find it quite interesting, but you have to be careful because it involves driving safety. First, gather some tools: the new brake fluid must meet your car's DOT standard, like the DOT4 I used, a fluid extractor or plastic tube, and have a wrench ready. Park on a level surface and engage the handbrake, preferably with a helper to assist with pressing the brake pedal. Open the hood and locate the brake fluid reservoir, then unscrew the cap. Start bleeding from the brake caliper farthest from the wheels, usually the rear ones, such as the right rear wheel. Connect the tool to the bleeder valve and slowly loosen it—the old fluid will drain out while the helper presses the brake pedal to help expel the fluid. Keep adding new fluid to the reservoir as you bleed, ensuring the fluid level doesn't drop below the minimum line to avoid air getting in, which would cause trouble. Once the fluid changes from old to new and appears clear, move on to the next wheel. Typically, all four wheels take about half an hour. Finally, check for air bubbles by pressing the pedal firmly to see if it feels spongy—if so, you'll need to re-bleed. After finishing, test the car at low speed to check brake responsiveness. Do this every one or two years—don't slack off, as old fluid absorbs moisture and can corrode components.
