Bobcat 773 Skid Steer Loader: Troubleshooting Common Hydraulic and Electrical Issues

[MikePhua]

The Bobcat 773, a versatile skid steer loader, is widely utilized in construction, landscaping, and agricultural applications. However, like all machinery, it can experience operational challenges. This guide delves into common hydraulic and electrical issues faced by Bobcat 773 owners and provides practical solutions to address them.
Hydraulic System Challenges

1. Intermittent Boom and Tilt Functionality
   Operators have reported instances where the boom and tilt functions become unresponsive, despite the engine running smoothly. This issue often arises from malfunctions in the hydraulic valve block or internal spool sticking. Even with adequate fluid levels and clean filters, debris or wear within the control valve can restrict flow, leading to inconsistent operation. Inspecting and cleaning the valve block, and replacing worn components, can restore functionality.
   
2. Hydraulic Pressure Release Valve Failure
   A malfunctioning pressure release valve can cause excessive hydraulic pressure, leading to engine stalling. If the pressure isn't adequately released, it may bind other parts, preventing movement. Rebuilding or replacing the pressure release valve, often located near the control valve, is recommended to resolve this issue.
   
3. Slow or Unresponsive Auxiliary Hydraulics
   Slow or unresponsive auxiliary hydraulics can result from issues with the auxiliary hydraulic pump, clogged filters, or low hydraulic fluid levels. Regular maintenance, including checking fluid levels and replacing filters, can prevent these problems. Additionally, inspecting the hydraulic pump for wear or damage ensures optimal performance.
   

Electrical System Troubles

1. Startup Failures and No Response
   If the Bobcat 773 shows no lights or starts, it's essential to verify the battery's health and ensure all cable connections are secure. Corrosion or loose connections can impede electrical flow. Cleaning the battery terminals and inspecting the wiring harness for damage can often resolve these startup issues.
   
2. Flashing Parking Brake Light
   A flashing parking brake light typically indicates a brake system fault or sensor error. Ensure the parking brake lever is fully disengaged. Inspect the brake override button and wiring for damage or poor connections. The system may prevent movement if it detects the brake engaged. Resetting the system by cycling power or consulting the service manual for brake sensor diagnostics can resolve the issue.
   
3. BICS (Bobcat Interlock Control System) Problems
   The BICS system ensures safety by preventing unintended machine movement. Issues such as a flashing parking brake light or unresponsive controls can stem from sensor malfunctions or wiring problems. Inspecting and cleaning connectors, especially those near the seat bar switch, can address these concerns. In some cases, replacing faulty sensors or components may be necessary.
   

Preventive Maintenance Tips

• Regular Fluid Checks: Ensure that hydraulic and engine fluids are at appropriate levels and are free from contaminants.
  
• Inspect Hydraulic Components: Regularly check hoses, filters, and seals for wear or damage. Replace any compromised components promptly.
  
• Electrical System Maintenance: Periodically clean battery terminals and inspect wiring for signs of wear or corrosion.
  
• System Calibration: Ensure that control systems, including the BICS, are properly calibrated to prevent operational issues.
  

Conclusion
The Bobcat 773 is a reliable and powerful skid steer loader when properly maintained. By proactively addressing common hydraulic and electrical issues, operators can ensure optimal performance and longevity of their equipment. Regular maintenance and timely repairs are key to keeping the Bobcat 773 running smoothly and efficiently.