Troubleshooting Intermittent Track Power Loss on Case 850 Dozers

[MikePhua]

Experiencing intermittent track power loss on a Case 850 dozer, especially on inclines, can be perplexing. A user reported that after pushing dirt for over 120 hours, the machine performed flawlessly on flat ground and uphill but began losing power to the tracks when operating on a slight incline or when pushing downhill and attempting to back up. Interestingly, the power would return after moving to level ground for a brief period. This issue persisted despite thorough maintenance, including replacing all filters and screens during the refurbishment.
Potential Causes and Diagnostic Steps

1. Hydraulic Fluid Levels and Quality
   Low or contaminated hydraulic fluid can lead to insufficient pressure, affecting track performance. It's crucial to check the hydraulic fluid levels and ensure they are within the recommended range. Additionally, inspect the fluid for contamination or degradation, which can impair system function.
   
2. Transmission and Final Drive Systems
   The transmission and final drive systems are integral to track movement. Issues such as low fluid levels, worn components, or internal leaks can cause power loss. Regular maintenance and timely replacement of worn parts are essential to prevent such problems.
   
3. Brake System Malfunctions
   A malfunctioning brake system can impede track movement. For instance, a user reported that the left track on a Case 850K dozer wouldn't operate, and upon inspection, it was found that the brake system wasn't releasing properly. After checking the brake pressure and solenoid function, the issue was traced back to a faulty brake system component.
   
4. Hydraulic Control Valves and Filters
   Clogged or malfunctioning hydraulic control valves can disrupt fluid flow, leading to power loss. It's advisable to inspect and clean all hydraulic filters and control valves regularly to ensure optimal performance.
   

Recommended Solutions

• Regular Maintenance: Adhere to the manufacturer's recommended maintenance schedule, including timely replacement of filters and fluids.
  
• System Inspections: Conduct thorough inspections of the hydraulic, transmission, final drive, and brake systems to identify and address potential issues promptly.
  
• Professional Assistance: If the problem persists after performing basic diagnostics and maintenance, consider seeking assistance from a professional technician with experience in Case dozers.
  

Conclusion
Intermittent track power loss on a Case 850 dozer can stem from various issues, including hydraulic fluid problems, transmission or final drive malfunctions, brake system failures, and hydraulic control valve obstructions. By systematically diagnosing and addressing these potential causes, operators can restore their dozer's performance and prevent future occurrences.