How to Bleed Brakes on a CAT 953 20Z01 A-Series Loader

[MikePhua]

Proper brake maintenance is essential for the safety and performance of any heavy equipment. One common procedure that operators may need to perform on their CAT 953 20Z01 A-Series loader is bleeding the brakes. This process is crucial when the brake system has air in the lines, which can lead to poor brake performance. This article will guide you through the steps for bleeding the brakes on a CAT 953 20Z01 A-Series loader, ensuring that your equipment remains safe and functional.
Why Bleed the Brakes?
Bleeding the brakes is necessary when there is air in the brake lines, which can occur if there is a leak in the hydraulic brake system or after changing brake fluid. Air in the brake lines prevents the proper application of pressure, resulting in spongy or unresponsive brakes. Bleeding the brakes helps to remove air from the hydraulic system, restoring normal brake function.
Required Tools and Equipment
Before starting the brake bleeding process, make sure you have the following tools and equipment:

• Wrenches or Brake Bleeding Tools: You’ll need the correct size wrenches or a specialized brake bleeder kit.
  
• Brake Fluid: Ensure you have the right type of brake fluid for the CAT 953.
  
• Clear Tubing: This is used to observe the flow of brake fluid and air from the bleed valve.
  
• Container for Used Fluid: Have a container ready to catch the used brake fluid during the process.
  

Steps to Bleed the Brakes on a CAT 953 20Z01 A-Series Loader
Follow these steps to successfully bleed the brakes on your CAT 953 20Z01 A-Series loader:

1. Ensure Safety: Before starting, make sure the loader is parked on a flat, level surface, and the parking brake is engaged. Place wheel chocks around the wheels to prevent the machine from moving during the process.
   
2. Locate the Brake Bleed Valve: The brake bleed valve is typically located near each wheel or on the brake cylinder. Consult the loader’s manual for the exact location. You may need to remove covers or shields to access the valve.
   
3. Attach the Bleeding Kit: Attach one end of the clear tubing to the brake bleed valve and place the other end in a container to catch the used brake fluid. Make sure the tubing is securely connected to avoid leaks.
   
4. Loosen the Bleed Valve: Using the appropriate wrench, loosen the brake bleed valve. You should start with the wheel that is farthest from the master cylinder (usually the passenger side rear). This ensures air and fluid are pushed toward the master cylinder.
   
5. Pump the Brake Pedal: Have an assistant sit in the operator’s seat and slowly pump the brake pedal a few times to build up pressure. Instruct them to hold the pedal down once it feels firm. While they hold it, you will release the brake bleed valve to allow air and brake fluid to escape.
   
6. Close the Valve: After the air and brake fluid flow through the tubing and into the container, close the bleed valve before the assistant releases the brake pedal. This prevents air from re-entering the brake lines.
   
7. Repeat the Process: Repeat this process for each wheel, starting from the farthest and working your way toward the closest. Always ensure the brake fluid reservoir stays filled during the bleeding process, topping it off as needed to avoid introducing air into the system.
   
8. Check for Air-Free Fluid: As you bleed the brakes, watch for air bubbles in the clear tubing. Once no more bubbles appear, and only clean brake fluid is coming out, the brake lines are fully bled. You may want to perform this process a few times for thoroughness.
   
9. Test Brake Pedal: After completing the bleeding process, test the brake pedal by pressing it. The pedal should feel firm and responsive. If the pedal still feels spongy, repeat the bleeding procedure until all air has been removed from the system.
   

Dispose of Used Brake Fluid Properly
Brake fluid is toxic and should not be poured onto the ground. Dispose of the used brake fluid in accordance with local environmental regulations. Many auto parts stores and service centers accept used fluid for proper disposal.
Conclusion: Ensuring Brake Performance
Bleeding the brakes on your CAT 953 20Z01 A-Series loader is a straightforward process that can be done with the right tools and a little time. By regularly checking and maintaining the brake system, you ensure that the loader remains safe and operational, preventing issues that could arise from air in the brake lines. Proper brake function is critical for safe operation, especially when working with heavy loads and in demanding environments.