Bobcat 853 Traction Lock Solenoid Not Locking Wheels: Troubleshooting and Solutions

[MikePhua]

The Bobcat 853 is a well-known skid-steer loader, widely used for its maneuverability and power in various applications. However, like all machinery, it can encounter issues over time. One common problem reported by operators is when the traction lock solenoid fails to lock the wheels. This issue can prevent the skid-steer from engaging the proper traction and power, which is critical for certain tasks. In this article, we will explore potential causes and solutions for this problem.
Understanding the Traction Lock Solenoid System

1. What Is the Traction Lock Solenoid?
   The traction lock solenoid is part of the drive system on the Bobcat 853. It works by controlling the engagement of the wheels, allowing the operator to lock or unlock the wheels based on the task at hand. This solenoid ensures that the machine has the necessary traction when working in tough or uneven conditions, such as on steep terrain or in muddy environments.
   
2. How the Traction Lock Works
   When the solenoid is activated, it locks the wheels, providing more power and control. When disengaged, the wheels rotate independently, allowing for easier turning and maneuvering in tight spaces.
   

Common Causes of Traction Lock Solenoid Failure

1. Electrical Issues
   One of the most common causes for a non-working traction lock solenoid is an electrical issue, such as a blown fuse, a faulty relay, or a broken wire connection. The solenoid relies on electrical power to engage, and if the circuit is not complete, the wheels will not lock.
   • Solution:
     • Inspect the fuse and relays related to the traction lock system.
       
     • Check all wiring connections to ensure they are intact and properly connected.
       
     • Use a multimeter to test for continuity and proper voltage at the solenoid.
       
2. Solenoid Failure
   The solenoid itself could be defective or worn out. Over time, solenoids can fail due to wear and tear, particularly if the machine has been in use for a long period or exposed to harsh working conditions.
   • Solution:
     • Inspect the solenoid for signs of damage, corrosion, or wear.
       
     • If necessary, replace the solenoid with a new one.
       
     • Check the solenoid’s functionality using a voltmeter to ensure it’s receiving proper electrical signals.
       
3. Hydraulic Issues
   Hydraulic pressure plays a significant role in locking the wheels. If the hydraulic system is not providing enough pressure, it can cause the solenoid to malfunction. Low hydraulic fluid levels, leaks, or pump failure can contribute to this issue.
   • Solution:
     • Check the hydraulic fluid levels and top up if necessary.
       
     • Inspect the hydraulic lines and hoses for leaks or blockages.
       
     • Test the hydraulic pump to ensure it is functioning correctly and providing adequate pressure.
       
4. Contaminated or Low-Quality Fluid
   Contaminated or low-quality hydraulic fluid can affect the solenoid’s ability to lock the wheels. Fluid that is dirty or degraded can cause blockages or inconsistent pressure, leading to solenoid malfunctions.
   • Solution:
     • Flush the hydraulic system and replace the fluid with high-quality hydraulic oil.
       
     • Regularly maintain the hydraulic fluid to ensure optimal performance.
       

Steps to Diagnose and Fix the Traction Lock Issue

1. Step 1: Check Electrical Connections
   Begin by inspecting the electrical components related to the traction lock system. Ensure that all fuses, relays, and wiring are intact. Use a multimeter to verify that the solenoid is receiving the correct voltage and current.
   
2. Step 2: Test the Solenoid
   If the electrical system is functioning correctly, the next step is to test the solenoid itself. Disconnect the solenoid and check for continuity. If it shows signs of wear or failure, replace it with a new one.
   
3. Step 3: Inspect the Hydraulic System
   After confirming the solenoid is working properly, check the hydraulic system. Ensure that the fluid levels are adequate, and inspect the lines for any leaks. Also, check the pump to make sure it’s delivering proper hydraulic pressure to the solenoid.
   
4. Step 4: Replace the Fluid
   If the hydraulic fluid is dirty or low-quality, replace it with fresh, high-quality fluid. This can help restore proper pressure and performance to the traction lock system.
   

Preventive Maintenance Tips

1. Regularly Check Hydraulic Fluid Levels
   Keeping the hydraulic fluid at the proper levels is crucial for the performance of the traction lock solenoid and other hydraulic components. Regularly check and top up the fluid as necessary.
   
2. Inspect Electrical Components Periodically
   Over time, wires and fuses can degrade or become loose. Periodically inspect the electrical components to ensure they are in good working condition. Replace any faulty parts immediately to prevent future issues.
   
3. Service the Solenoid and Hydraulic System
   Regular servicing of the solenoid and hydraulic system can help prevent problems before they arise. Schedule routine maintenance to clean the solenoid, check hydraulic pressure, and replace fluid as needed.
   

Conclusion
When the traction lock solenoid on a Bobcat 853 fails to lock the wheels, it can hinder the machine’s performance and make it difficult to complete tasks efficiently. However, with proper troubleshooting and maintenance, the issue can often be resolved. Common causes include electrical issues, solenoid failure, and hydraulic problems. By following a systematic approach to diagnosing and fixing the issue, operators can restore their Bobcat 853 to full functionality and ensure it continues to perform at its best. Regular maintenance, such as checking fluid levels and inspecting electrical connections, will help prevent this issue from recurring in the future.