1. Preparation:
* Safety First: Always engage the parking brake firmly. Chock the wheels opposite the ones you're working on for added safety. Wear safety glasses.
* Gather Supplies: You'll need a new bleeder screw (matching the original's specifications – size and thread pitch are critical!), a wrench (usually 8mm or 10mm, but check your vehicle's specifications), a container to catch brake fluid, clean rags, and possibly some brake fluid (depending on whether you need to bleed the brakes afterward). A tubing adapter to attach to the bleeder screw is helpful for cleaner fluid collection and avoids spills.
* Locate the Bleeder Screws: These are typically located on the wheel cylinder at the top of each brake drum. They are small screws with a small hole.
2. Removing the Old Bleeder Screw:
* Clean the Area: Clean the area around the bleeder screw with a rag and brake cleaner to remove dirt and debris that could contaminate the brake system.
* Loosen the Screw: Using the correct size wrench, carefully loosen the bleeder screw by turning it counter-clockwise. Do not remove it completely yet. A small amount of brake fluid may leak out at this stage – that's normal.
* Prepare for Fluid Collection: Position your container and tubing (if using) to collect the leaking brake fluid.
3. Removing and Replacing the Bleeder Screw:
* Completely Remove the Old Screw: Once loosened, carefully unscrew the bleeder screw completely and remove it.
* Inspect the Wheel Cylinder: Inspect the wheel cylinder threads for damage. If damaged, you may need a wheel cylinder repair or replacement.
* Install the New Bleeder Screw: Lightly lubricate the threads of the new bleeder screw with brake fluid. Carefully screw it into the wheel cylinder by hand, ensuring it's straight and threads smoothly. Do not overtighten.
* Tighten the New Screw: Once hand-tight, use your wrench to tighten the new bleeder screw to the manufacturer's specified torque. Over-tightening can damage the threads and the wheel cylinder. Consult your vehicle's repair manual for the correct torque specification. If you don't have the manual, lightly snug it; don't force it.
4. Bleeding the Brakes (Usually Necessary):
* Because you've opened the brake system, you'll almost certainly need to bleed the brakes to remove any air that might have entered. This is usually done with a helper pushing the brake pedal while you open and close the bleeder screws. There are many resources online and in repair manuals explaining brake bleeding procedures. Always follow the proper bleeding sequence (usually starting at the furthest wheel from the master cylinder and working your way closer).
Important Notes:
* Brake Fluid is Corrosive: Brake fluid is corrosive and can damage paint. Clean up any spills immediately.
* Use the Correct Brake Fluid: Use the correct type of brake fluid specified for your vehicle. Using the wrong fluid can damage your brake system.
* If Unsure, Seek Professional Help: If you are uncomfortable performing this task yourself, take your vehicle to a qualified mechanic. Improperly bled brakes are dangerous.
By following these steps carefully, you can successfully replace bleeder screws on your drum brakes. Remember safety is paramount, and if in doubt, consult a professional.
