Maintaining and Changing Hydraulic Fluid in Older Case Drott Equipment

[MikePhua]

Introduction: The Importance of Regular Hydraulic Fluid Maintenance
Older Case Drott machines, such as the 40 BEC excavator, are renowned for their durability and simplicity. However, as with any heavy equipment, regular maintenance is crucial to ensure optimal performance and longevity. One of the most vital maintenance tasks is changing the hydraulic fluid. Over time, hydraulic fluid can degrade, leading to reduced efficiency and potential damage to the system.
Understanding the Hydraulic System
The hydraulic system in Case Drott equipment typically utilizes gear pumps, which are less sensitive to the type of hydraulic fluid used compared to modern piston pumps. This design allows for more flexibility in choosing suitable hydraulic fluids. However, it's essential to select a fluid that meets the system's operational requirements to maintain performance and prevent wear.
Recommended Hydraulic Fluids
For the Case Drott 40 BEC excavator, the manual recommends using Drott DHF fluid. Alternatively, SAE 20W-20W oil is acceptable for operating temperatures ranging from 50°F to 210°F (10°C to 99°C). This viscosity range ensures proper lubrication and system efficiency. However, some operators have successfully used ISO 46 hydraulic oil as a substitute, noting that while it may cause the system to operate more sluggishly in colder temperatures, it performs adequately in warmer conditions.
Procedure for Changing Hydraulic Fluid

1. Preparation
   • Ensure the machine is on a level surface and the engine is turned off.
     
   • Place a large drain pan beneath the hydraulic reservoir to catch the old fluid.
     
2. Draining the Old Fluid
   • Locate the drain plug at the bottom of the hydraulic reservoir.
     
   • Remove the drain plug and allow the fluid to drain completely.
     
   • To evacuate as much fluid as possible, retract all cylinders fully.
     
3. Flushing the System (Optional but Recommended)
   • After draining, refill the reservoir with a small amount of fresh hydraulic fluid.
     
   • Cycle the hydraulic system by operating the controls to flush out any remaining old fluid.
     
   • Drain the system again to remove the flushing fluid.
     
4. Refilling with New Hydraulic Fluid
   • Fill the reservoir with the recommended hydraulic fluid up to the specified level.
     
   • Check for any leaks around the drain plug and fill cap.
     
5. System Check
   • Start the engine and operate the hydraulic system to ensure proper function.
     
   • Check the hydraulic fluid level again and top off if necessary.
     

Maintenance Tips

• Regular Fluid Changes: It's advisable to change the hydraulic fluid every 1,000 hours of operation or annually, whichever comes first.
  
• Filter Maintenance: Replace hydraulic filters during each fluid change to prevent contamination and ensure efficient system operation.
  
• System Monitoring: Regularly check for signs of hydraulic fluid contamination, such as discoloration or the presence of particles.
  
• Proper Storage: Store hydraulic fluid in clean, sealed containers to prevent contamination before use.
  

Conclusion
Maintaining the hydraulic system of older Case Drott equipment is essential for ensuring its continued performance and longevity. By following the recommended procedures for changing hydraulic fluid and selecting the appropriate fluid type, operators can keep their machines running smoothly and efficiently. Regular maintenance not only enhances performance but also helps in identifying potential issues before they become major problems, saving time and money in the long run.