Terex Posi-Track: Issues with Bucket Curl and Boom Lifts

[MikePhua]

Introduction
The Terex Posi-Track is a versatile and durable piece of equipment used for a variety of tasks in the construction and agricultural sectors. However, like any heavy machinery, it can experience issues that interfere with its performance. One of the common problems reported by operators is a malfunction where the bucket curl is stuck, and the boom lifts when the controller is pushed into the boom down position. This issue can cause operational disruptions and safety concerns. In this article, we will explore potential causes for this malfunction and offer solutions to fix the issue.
Symptoms of the Problem
When this issue occurs, the operator may notice that while attempting to lower the boom, the bucket becomes stuck in the curled position. Simultaneously, the boom lifts instead of lowering as expected. This malfunction creates confusion in operation and can make it difficult to perform tasks effectively, such as digging or lifting materials.
Possible Causes and Solutions

1. Hydraulic Valve Malfunction
   • Cause: A common cause of this issue could be a malfunction in the hydraulic control valves. These valves are responsible for controlling the flow of hydraulic fluid to various parts of the machine, including the boom and bucket. If the valve is stuck or malfunctioning, it may send fluid to the wrong hydraulic cylinders, causing the boom to lift instead of lowering.
     
   • Solution: Inspect the hydraulic valves and check for any signs of blockages or damage. If any valves are faulty, they should be replaced or repaired by a qualified technician.
     
2. Controller or Joystick Issue
   • Cause: The issue could also stem from the joystick or control panel, which is responsible for sending the right signals to the hydraulic system. If the joystick is misaligned, damaged, or has an electrical fault, it could send incorrect commands to the machine, causing unintended movements such as the boom lifting instead of lowering.
     
   • Solution: Test the joystick’s functionality by checking if all control inputs respond correctly. If there is an issue with the joystick, it may need to be recalibrated or replaced.
     
3. Hydraulic Cylinder Malfunction
   • Cause: Hydraulic cylinders are responsible for moving the boom and bucket. A malfunction in one of these cylinders, such as internal wear, leaking seals, or damage to the piston, could cause abnormal movement or prevent the bucket from releasing from its curled position.
     
   • Solution: Inspect the hydraulic cylinders on both the boom and bucket for any visible signs of damage, such as oil leaks or abnormal wear. If necessary, replace or repair the damaged cylinder.
     
4. Faulty Wiring or Electrical Issue
   • Cause: Wiring problems or electrical issues in the system can also cause the bucket and boom to operate incorrectly. A short circuit or faulty relay in the electrical system may disrupt the signals sent from the controller, causing the boom to lift instead of lowering.
     
   • Solution: Check the wiring and electrical connections for any damage or loose connections. Ensure that all relays and electrical components are functioning properly. If any faulty wiring or components are found, they should be replaced or repaired.
     
5. Control Linkage Problem
   • Cause: The linkage that connects the controller to the hydraulic system may become worn or misaligned over time. If the linkage is not functioning properly, it could lead to improper movement of the boom and bucket, especially if the system is not engaging the correct hydraulic cylinders.
     
   • Solution: Inspect the control linkage and make sure it is properly aligned and lubricated. If the linkage shows signs of wear or misalignment, it should be adjusted or replaced.
     

Preventative Maintenance Tips
To prevent similar issues from occurring in the future, regular maintenance is essential. Here are a few tips to ensure the Terex Posi-Track operates smoothly:

1. Regularly Inspect Hydraulic Systems: Perform routine checks on hydraulic fluid levels, hoses, valves, and cylinders. Look for signs of leaks or wear, and replace any damaged components promptly.
   
2. Calibrate the Controls: Ensure that the joystick and controller are correctly calibrated to ensure proper response. This can help prevent miscommunications between the operator and the machine’s hydraulic system.
   
3. Check Electrical Connections: Regularly inspect the wiring and electrical connections for any signs of corrosion or damage. Tighten any loose connections and replace any damaged components.
   
4. Lubricate Linkages: Keep the control linkages properly lubricated to reduce wear and ensure smooth operation. Proper lubrication can also help reduce friction and prevent premature damage.
   

Conclusion
The issue of the Terex Posi-Track bucket curl being stuck and the boom lifting instead of lowering can be frustrating, but with the right troubleshooting steps, it can be resolved. Possible causes include hydraulic valve malfunctions, joystick issues, hydraulic cylinder damage, electrical faults, and control linkage problems. By regularly inspecting and maintaining the machine’s hydraulic system, controls, wiring, and linkages, operators can reduce the likelihood of similar issues occurring in the future and ensure safe and efficient operation.