how to change a wheel cylinder on drum brakes

How to Change a Wheel Cylinder on Drum Brakes

If you're experiencing problems with your drum brakes, such as leaking brake fluid or poor braking performance, it may be time to change the wheel cylinder. The wheel cylinder is a crucial component of the drum brake system, responsible for pushing out the brake shoes against the drum and allowing you to stop smoothly. Changing a wheel cylinder may seem daunting, but with the right tools and a little guidance, you can accomplish this task yourself. Here’s a step-by-step guide to help you through the process.

Tools and Materials Needed

Before you begin, gather the necessary tools and materials. You will need - New wheel cylinder - Brake fluid - Brake cleaner - Jack and jack stands - Lug wrench - Socket set - Line wrench - Brake shoe tool kit (if necessary) - Torque wrench - Safety goggles and gloves - Rags for cleanup

Step 1 Prepare the Vehicle

Before starting any work, ensure the vehicle is parked on a flat surface and is stable. Engage the parking brake and wear safety goggles and gloves for protection. Use the lug wrench to loosen the lug nuts on the wheel you will be working on but do not remove them completely yet.

Step 2 Lift the Vehicle

Next, use a hydraulic jack to lift the vehicle. Once elevated, securely place jack stands under the vehicle to ensure it won’t collapse while you're working. Finish removing the lug nuts and take off the wheel to expose the drum brake assembly.

Step 3 Remove the Brake Drum

Remove the brake drum by pulling it straight off the hub. If it’s stuck, you may need to tap it gently with a rubber mallet. Inspect the drum for damage, and if it’s scored or worn, consider replacing it, as well.

Step 4 Access the Wheel Cylinder

With the drum removed, you’ll have access to the brake shoes and the wheel cylinder. Before disconnecting any brake lines, it’s important to have a catch pan or rags ready, as brake fluid will likely leak out.

Step 5 Disconnect the Brake Lines

Using a line wrench, carefully disconnect the brake lines from the old wheel cylinder. Be cautious not to damage the lines; if necessary, use brake cleaner to clean any dirt or debris around the fittings to avoid contamination.

Locate the retaining screws or bolts holding the wheel cylinder in place and use a socket set to remove them. Once removed, gently pull the old wheel cylinder out of the assembly.

Step 7 Install the New Wheel Cylinder

Take the new wheel cylinder and install it in the same position as the old one. Secure it with the retaining screws or bolts, ensuring it's tightly fastened to prevent future leaks.

Step 8 Reconnect the Brake Lines

Reconnect the brake lines to the new wheel cylinder, tightening them securely with the line wrench. This is crucial to avoid any leaks when you fill the system with brake fluid.

Step 9 Reassemble the Brake Components

Replace the brake shoes if necessary, and reassemble all components in reverse order. Make sure everything is properly aligned and secured before proceeding.

Step 10 Reinstall the Brake Drum and Wheel

Slide the brake drum back onto the hub, followed by the wheel. Hand-tighten the lug nuts before lowering the vehicle back to the ground.

Step 11 Bleed the Brakes

After reinstalling the wheel, it’s important to bleed the brake system to remove any air that may have entered during the process. Start by having someone help you pump the brake pedal while you open and close the bleeder valve on the wheel cylinder. Repeat until you see a steady stream of fluid without bubbles.

Step 12 Test the Brakes

Once you’ve reassembled everything, perform a visual inspection to ensure all tools and components are accounted for. Start the vehicle and gently press the brake pedal to check for any leaking fluid. Take your vehicle for a test drive to ensure the brakes function properly.

Conclusion

Changing a wheel cylinder on drum brakes can save you money and give you confidence in handling your vehicle’s maintenance. With careful attention to detail and following these steps, you can replace the wheel cylinder without professional help. Always consult your vehicle’s service manual for specific instructions related to your make and model. Safety first if at any point you feel unsure, don’t hesitate to seek the help of a qualified mechanic.