how to bleed back drum brakes

How to Bleed Back Drum Brakes A Step-by-Step Guide

Bleeding drum brakes is a crucial maintenance task that ensures your braking system functions efficiently. Over time, air can enter the brake lines, leading to a spongy feel in the brake pedal and decreased stopping power. This article will guide you through the process of bleeding back drum brakes, ensuring your brake system operates at its best.

Understanding Drum Brakes

Before we dive into the bleeding process, it's important to understand how drum brakes work. Drum brakes consist of a drum (the circular component) that houses the brake shoes. When the brake pedal is pressed, hydraulic pressure pushes the shoes against the inside of the drum, creating friction that slows down the vehicle. If air gets into the brake lines, it can compress and create bubbles, resulting in a brake system that feels soft or unresponsive.

Tools and Supplies Needed

To bleed your drum brakes, you will need

- A brake bleeder kit (or a clear plastic tube and a container) - Brake fluid (make sure to use the recommended type for your vehicle) - A wrench (usually a 10mm or 12mm, depending on your brake bleeder screw) - A helper (optional, but recommended for efficiency) - Safety goggles and gloves - Jack and jack stands (or a hydraulic lift)

Step-by-Step Guide to Bleeding Drum Brakes

Step 1 Prepare Your Vehicle

1. Safety First Ensure the vehicle is parked on a level surface. Engage the parking brake and wear safety goggles and gloves to protect yourself from brake fluid, which can damage paint and other surfaces. 2. Raise the Vehicle Use a jack to lift the rear of the car, and set it securely on jack stands. This allows for easier access to the drum brakes.

Step 2 Locate the Bleeder Screws

Drum brakes typically have a bleeder screw located at the top of the wheel cylinder. Consult your vehicle’s service manual for the exact location if you’re unsure.

Step 3 Remove the Brake Fluid Reservoir Cap

Open the hood and locate the brake fluid reservoir. Remove the cap to allow air in while you bleed the brakes. Keep an eye on the fluid level during the process and replenish as necessary to avoid introducing more air into the system.

1. Connect the Bleeder Kit If you’re using a brake bleeder kit, connect the hose to the bleeder screw, placing the other end in the container. If you’re doing it manually, slip a clear plastic tube over the screw, placing the end into a container to catch fluid.

2. Loosen the Bleeder Screw Using the wrench, gently loosen the bleeder screw. Be careful not to remove it completely.

3. Pump the Brakes If you have a helper, instruct them to pump the brake pedal several times and then hold it down. If you’re doing this alone, you can press the pedal down and hold it.

4. Open the Bleeder Screw While the pedal is held down, slowly open the bleeder screw. You should see brake fluid (and possibly air bubbles) flowing out. Once the fluid runs clear without bubbles, close the screw before the helper releases the brake pedal.

5. Repeat the Process Repeat this process until you have a steady stream of clear brake fluid with no air bubbles. It may take several cycles to fully bleed the brakes.

Step 5 Final Steps

1. Check Fluid Levels After bleeding, make sure to check and top up the brake fluid in the reservoir as necessary.

2. Test the Brakes Before driving, pump the brake pedal a few times to ensure it feels firm. If it still feels spongy, you may need to repeat the bleeding process.

3. Dispose of Brake Fluid Properly dispose of any used brake fluid according to local regulations.

Conclusion

Bleeding back drum brakes is a straightforward process that can enhance the safety and efficiency of your vehicle. Regular maintenance, including ensuring your brake system is free of air, will contribute to better braking performance and help avoid costly repairs in the future. If you're ever unsure, consult a professional mechanic for assistance. Remember, your safety relies heavily on your braking system, so don’t hesitate to give it the care it deserves!