Troubleshooting Guide: Case 850 Slowing Down

[MikePhua]

Introduction to the Case 850
The Case 850 is a powerful and reliable crawler dozer used for various heavy-duty tasks, including construction, grading, and landscaping. However, like any piece of machinery, the Case 850 may experience performance issues, such as slowing down unexpectedly. A dozer that slows down during operation can lead to significant downtime and reduced efficiency on the job site.
In this article, we will go through several common reasons why the Case 850 may be slowing down and provide troubleshooting steps to help resolve these issues.
Step 1: Check the Transmission Fluid

1. Low or Contaminated Fluid
   • One of the most common causes of slow performance in a dozer like the Case 850 is low or contaminated transmission fluid. Low fluid levels can lead to insufficient pressure, making it difficult for the machine to operate efficiently. Contaminated fluid can also affect the transmission's performance.
     
2. Solution
   • Start by checking the transmission fluid level and ensuring it is within the recommended range. If the fluid appears dirty, discolored, or has metal shavings, it’s time to change the fluid and replace the filter. Regular fluid changes are key to maintaining the health of the transmission system.
     

Step 2: Inspect the Transmission System

1. Transmission Slipping or Sticking
   • If the transmission is slipping or not engaging properly, it can cause the dozer to slow down or lose power. This could be due to a variety of issues such as worn-out clutch packs, faulty solenoids, or problems with the gear linkage.
     
2. Solution
   • Inspect the transmission system for any signs of wear or damage. If the problem is related to slipping or poor engagement, it may be necessary to check and replace clutch packs or transmission solenoids. A professional diagnostic may be required to ensure the internal components of the transmission are functioning properly.
     

Step 3: Inspect the Fuel System

1. Fuel Flow Issues
   • Insufficient fuel flow can cause the Case 850 to lose power and slow down. This could be due to a clogged fuel filter, dirty fuel lines, or a malfunctioning fuel pump.
     
2. Solution
   • Check the fuel filter for any clogs or signs of debris. If the fuel filter is dirty, replace it with a new one. Inspect the fuel lines for cracks or blockages that may be restricting fuel flow. If the fuel pump is malfunctioning, it may need to be repaired or replaced.
     

Step 4: Check the Air Filter

1. Clogged Air Filter
   • A clogged air filter can reduce the amount of air reaching the engine, which can cause the engine to run inefficiently and slow down. This issue is common in dozers working in dusty environments.
     
2. Solution
   • Inspect the air filter for dirt, debris, or damage. If the air filter is clogged, replace it with a new one. Regularly clean or replace the air filter to prevent buildup and ensure proper airflow to the engine.
     

Step 5: Inspect the Cooling System

1. Overheating
   • If the cooling system is not functioning properly, the engine may overheat, causing the machine to slow down or shut down completely. Overheating can occur due to low coolant levels, a clogged radiator, or a malfunctioning thermostat.
     
2. Solution
   • Check the coolant levels and ensure there are no leaks in the system. Inspect the radiator for debris or dirt buildup that could block airflow. If the thermostat is malfunctioning, it may need to be replaced to maintain optimal engine temperature.
     

Step 6: Examine the Hydraulic System

1. Hydraulic Pressure Issues
   • The Case 850 uses hydraulic power to operate various systems, such as the blade and steering. If the hydraulic system is not working properly, it can cause sluggish performance and a reduction in the overall speed of the machine.
     
2. Solution
   • Inspect the hydraulic fluid levels and condition. If the fluid is low or contaminated, replace it and ensure the filter is clean. Check for leaks in the hydraulic hoses and lines that could be causing a loss of pressure. If the hydraulic pump or motor is faulty, it may need to be repaired or replaced.
     

Step 7: Check the Final Drive and Undercarriage

1. Undercarriage Wear
   • Worn-out components in the undercarriage, such as the tracks, rollers, and sprockets, can lead to poor performance and a reduction in speed. Excessive wear can create friction and resistance, making it harder for the dozer to move efficiently.
     
2. Solution
   • Inspect the tracks, sprockets, and rollers for signs of wear or damage. Replace any worn or damaged parts to reduce friction and restore smooth operation. Ensure that the track tension is properly adjusted to prevent excessive wear on the undercarriage.
     

Step 8: Perform a System Diagnostic Check

1. Electrical and Sensor Issues
   • Modern dozers like the Case 850 are equipped with various sensors and electrical components that control the machine’s performance. If there is an issue with the sensors, such as faulty speed or load sensors, it could result in the dozer slowing down.
     
2. Solution
   • Use an electronic diagnostic tool to check for any error codes or sensor malfunctions. If the diagnostic tool detects any issues with the sensors or electrical system, the faulty components should be replaced or repaired.
     

Step 9: Test and Verify

1. Initial Testing
   • After completing the troubleshooting steps, it’s important to test the Case 850 to verify whether the issue has been resolved. Start the machine and check for improved speed and responsiveness.
     
2. Solution
   • If the machine still slows down despite resolving the initial issues, further investigation may be needed. This could involve more in-depth diagnostics or professional assistance from a technician.
     

Conclusion
A Case 850 that is slowing down can be caused by a variety of factors, including transmission issues, fuel system problems, or even a dirty air filter. By following this troubleshooting guide, you can identify the root cause of the issue and take the necessary steps to restore the machine’s performance. Regular maintenance, including checking the fluids, filters, and hydraulic system, can help prevent these issues from arising and ensure that your Case 850 continues to perform at its best.