What you'll need:
* Brake fluid: Use DOT 3 brake fluid specifically. Do not use DOT 4 or 5. Using the wrong fluid can damage your system.
* Bleeding wrench: A wrench that fits your bleed nipples (usually 8mm or 10mm). A tubing wrench or open-end wrench works well.
* Clear tubing: A short length (about 18-24 inches) of clear plastic tubing to fit snugly over the bleed nipple.
* Container: A small container to collect the old brake fluid.
* Helper: You absolutely need someone to help pump the brake pedal.
* Gloves: Brake fluid is corrosive; protect your hands.
* Shop rags or paper towels: For cleaning up spills.
* Owner's manual (optional but recommended): Provides specific details for your model.
Procedure:
1. Locate the bleed nipples: These are located on each caliper (front and rear brakes). They typically have a small hexagonal opening for the wrench.
2. Check the brake fluid level: Make sure the master cylinder reservoir is full of fresh DOT 3 brake fluid. Top it off if needed. Do this frequently throughout the bleeding process as the fluid level will drop.
3. Prepare the system: Have your helper sit in the driver's seat with their foot on the brake pedal. Attach the clear tubing to the bleed nipple of the farthest wheel from the master cylinder (typically the right rear). Submerge the other end of the tubing into your container.
4. Bleeding sequence: The generally accepted bleeding sequence is:
* Right Rear
* Left Rear
* Right Front
* Left Front
* *Some mechanics prefer a diagonal pattern. Check your owner's manual for specifics.*
5. The bleeding process:
* Have your helper slowly and firmly pump the brake pedal several times. Tell them not to hold the pedal down.
* Once they're pumping, open the bleed nipple with your wrench about 1/4 to 1/2 turn. You should see brake fluid coming out of the tube.
* Let your helper release the brake pedal.
* Close the bleed nipple firmly once the flow of fluid slows to a drip or stops.
* Repeat steps 5a-5d several times until the fluid coming out of the bleed nipple is clean and free of air bubbles.
6. Move to the next wheel: Repeat steps 3-5 for each wheel, following the bleeding sequence. Keep an eye on the master cylinder reservoir and refill as needed. Low fluid level can introduce air.
7. Check for leaks: After bleeding all four wheels, carefully inspect all connections and fittings for any leaks.
8. Test the brakes: After bleeding, carefully test the brakes in a safe, open area, preferably away from traffic. The brake pedal should feel firm and responsive. If the pedal feels spongy or you notice any issues, you may need to repeat the bleeding process.
Important Considerations:
* Air in the lines: Air in the brake lines can significantly reduce braking performance, potentially leading to brake failure. This is why proper bleeding is crucial.
* Brake fluid is corrosive: Avoid getting it on your paint or skin.
* If you are not comfortable with this procedure, take your vehicle to a qualified mechanic. Bleeding brakes incorrectly can be dangerous.
This process outlines the general procedure. Consult your 1992 Chevy Lumina's owner's manual for specific instructions and diagrams relevant to your vehicle's brake system. The manual may specify a different bleeding sequence or provide additional details.
