Bobcat 864 Creep Issue Troubleshooting and Repair

[MikePhua]

The Bobcat 864 skid steer loader is an efficient and powerful machine, but some users may experience the "creeping" issue, where the machine slowly moves forward or backward even when no controls are being operated. This issue can affect the normal operation of the machine and may lead to unnecessary fuel consumption. This article outlines common causes of creeping in the Bobcat 864 and provides solutions to resolve the issue.
Common Causes

1. Control Valve Malfunction
   The control valve is a key component of the skid steer’s hydraulic system. If the control valve malfunctions, it can cause hydraulic leakage, leading to the machine creeping even when the operator is not using the controls.
   
2. Hydraulic System Leaks
   Leaks within the hydraulic system are a common cause of creeping. If hydraulic hoses or seals are damaged, hydraulic fluid may flow unevenly or excessively, causing the machine to move without input from the operator.
   
3. Unstable Hydraulic Pressure
   If the hydraulic pressure is unstable, the skid steer’s control system may fail to respond properly. Low hydraulic pressure can prevent the system from fully stopping the machine, leading to the creeping issue.
   
4. Hydraulic Pump Failure
   A malfunctioning hydraulic pump can lead to inadequate hydraulic pressure, affecting the machine’s response. Low hydraulic pressure can result in the machine not coming to a complete stop, causing creeping.
   
5. Faulty Valves or Sensors
   Faults in hydraulic valves or sensors can lead to improper functioning of the hydraulic system, which can cause the machine to creep. Faulty sensors may provide incorrect signals, leading to incorrect hydraulic flow distribution.
   
6. Control System Issues
   Electrical or signal issues in the control system may also result in improper hydraulic responses. If control signals are not being transmitted accurately, it may cause the hydraulic system to function unpredictably, leading to creeping.
   

Diagnostic Steps

1. Inspect the Control Valve
   Check the control valve for any signs of leakage or malfunction. Ensure that the valve seals are intact and that hydraulic fluid is flowing correctly through the system.
   
2. Check the Hydraulic System
   Inspect all hydraulic hoses, fittings, and seals for any signs of leaks. Use a pressure gauge to check the hydraulic system’s operating pressure to ensure it is within the specified range.
   
3. Check the Hydraulic Oil and Pump
   Inspect the hydraulic oil for proper levels and quality. Ensure that the hydraulic pump is functioning correctly and that the oil pressure is stable. Low oil pressure can directly contribute to the creeping problem.
   
4. Inspect the Electrical Control System
   If you suspect issues with the electrical control system, inspect the electrical connections and sensors. Use diagnostic tools to read any fault codes and address potential issues within the control system.
   
5. Examine Hydraulic Valves and Sensors
   Check the hydraulic valves and sensors for proper operation. Ensure that the valves are in the correct positions and that sensors are accurately transmitting signals to the control system.
   

Solutions

1. Repair or Replace the Control Valve
   If the control valve is leaking or malfunctioning, repair or replace it. Ensure that the seals are intact and that hydraulic fluid is directed appropriately to prevent any unwanted movement.
   
2. Fix Hydraulic System Leaks
   Thoroughly inspect the hydraulic system for any leaks and repair or replace damaged hoses and seals. This will restore proper fluid flow and help prevent the creeping issue.
   
3. Adjust or Replace the Hydraulic Pump
   If the hydraulic pump is faulty, consider adjusting its pressure settings or replacing it with a new one to ensure that the hydraulic system maintains stable pressure.
   
4. Fix Electrical Control System Issues
   Inspect the electrical control system for faulty wiring or malfunctioning sensors. Correct any issues with the electrical components, and ensure that the control system is sending proper signals to the hydraulic system.
   
5. Repair or Replace Hydraulic Valves and Sensors
   If any hydraulic valves or sensors are found to be faulty, repair or replace them. This will ensure that the hydraulic system responds accurately to the operator's commands and prevent unintended movement.
   

Conclusion
The creeping issue in the Bobcat 864 is typically caused by malfunctions in the control valve, hydraulic system leaks, unstable hydraulic pressure, hydraulic pump failure, electrical control system issues, or faulty hydraulic valves and sensors. By systematically diagnosing the hydraulic system, control valve, pump, and electrical components, users can effectively resolve the creeping problem. Regular maintenance of the hydraulic and control systems, along with timely repairs or replacements of faulty components, will help keep the machine running smoothly and prevent the creeping issue from recurring.