Troubleshooting Slow Walking Hydraulics in the CASE CX 135

[MikePhua]

The CASE CX 135 is a versatile and powerful crawler excavator, renowned for its robust hydraulic system and efficient performance on construction sites. However, like any piece of heavy equipment, it may face issues over time. One common problem that operators encounter is slow walking hydraulics, where the machine’s tracks move sluggishly or with a delay. This can lead to reduced operational efficiency and increased wear on the components if not addressed promptly. In this article, we’ll explore the potential causes of slow walking hydraulics in the CASE CX 135 and provide solutions to fix the issue.
Understanding Walking Hydraulics in Excavators
In an excavator, "walking hydraulics" refers to the hydraulic system responsible for powering the movement of the machine's tracks, allowing it to move forward or backward. The hydraulic system is essential for not only walking but also for lifting, digging, and rotating the excavator's boom and bucket. The speed and efficiency of the walking hydraulics are controlled by hydraulic pumps and valves, which regulate the flow and pressure of hydraulic fluid to the motors that drive the tracks.
When the walking hydraulics are not functioning correctly, it can manifest as sluggish movement or increased response time, which may affect the overall performance and maneuverability of the excavator.
Symptoms of Slow Walking Hydraulics
Slow walking hydraulics in the CASE CX 135 can present in a variety of ways. Recognizing the symptoms early can help in diagnosing and addressing the issue before it leads to further complications.

1. Sluggish Track Movement:
   • The most noticeable symptom of slow walking hydraulics is the slow movement of the tracks. The excavator may take longer than usual to start moving or may feel like it is struggling to move.
     
2. Uneven or Jerky Movement:
   • In some cases, the tracks may move unevenly or jerk, indicating a problem with the hydraulic fluid flow or pressure regulation. This can happen when the hydraulic system is not providing a consistent amount of power to the motors.
     
3. No Response to Pedal or Joystick Input:
   • Another indication of hydraulic issues is when the tracks fail to respond to the operator’s input on the joystick or foot pedals. This could point to a malfunction in the hydraulic system or the control valves.
     
4. Loss of Power:
   • If the machine struggles to move, especially when under load, it may indicate a loss of power in the hydraulic system, which can lead to slow walking or even a complete lack of movement.
     

Common Causes of Slow Walking Hydraulics
Several factors can contribute to slow walking hydraulics in the CASE CX 135. It is essential to systematically address these causes to restore the machine's normal operation.
1. Low or Contaminated Hydraulic Fluid
Hydraulic fluid plays a critical role in powering the walking system. If the fluid level is low or contaminated, the flow of hydraulic fluid can be reduced, leading to slow movement.

• Solution: Check the hydraulic fluid level and ensure it is within the manufacturer’s recommended range. If the fluid is contaminated, flush the system and replace it with fresh fluid. Be sure to use the correct type of hydraulic fluid as specified in the operator’s manual.
  

2. Worn Hydraulic Pump
The hydraulic pump is responsible for generating the pressure required to power the hydraulic system. Over time, the pump can wear out, resulting in inadequate hydraulic pressure and slow walking hydraulics.

• Solution: Inspect the hydraulic pump for any signs of wear or damage. If the pump is not generating sufficient pressure, it may need to be replaced or rebuilt. It is important to also check for any blockages in the hydraulic lines that could be restricting fluid flow.
  

3. Faulty Hydraulic Motors
The hydraulic motors that drive the tracks may become faulty or worn over time. If these motors fail to operate at full efficiency, it can lead to slow movement.

• Solution: Inspect the hydraulic motors for any signs of leaks, wear, or damage. If the motors are malfunctioning, they may need to be repaired or replaced. Pay attention to any unusual noises, vibrations, or overheating that could indicate a problem with the motors.
  

4. Blocked or Damaged Hydraulic Lines
Blocked or damaged hydraulic lines can restrict the flow of hydraulic fluid, leading to slow walking hydraulics. Even small leaks or blockages in the system can cause significant issues.

• Solution: Inspect the hydraulic lines for leaks, cracks, or blockages. Clean or replace any damaged lines to ensure smooth fluid flow. It may also be necessary to check the hydraulic filters, as clogged filters can also impede fluid circulation.
  

5. Faulty Control Valves
Control valves regulate the flow of hydraulic fluid to the various components of the machine, including the walking hydraulics. If these valves malfunction or become clogged, they can cause uneven or slow movement of the tracks.

• Solution: Inspect the control valves for any signs of damage or malfunction. If a valve is stuck or clogged, clean or replace it. Be sure to follow the manufacturer’s recommendations for valve maintenance.
  

6. Hydraulic Pressure Relief Valve Malfunction
The hydraulic pressure relief valve regulates the maximum pressure in the hydraulic system. If this valve is malfunctioning, it could cause a loss of pressure, resulting in slow or inefficient movement of the tracks.

• Solution: Check the hydraulic pressure relief valve to ensure it is functioning correctly. If the valve is defective, it should be replaced to restore normal hydraulic pressure.
  

7. Improperly Calibrated System
If the hydraulic system is not properly calibrated, it can lead to poor performance, including slow walking hydraulics. This issue may arise if components such as the hydraulic pumps, valves, or motors were recently replaced or serviced.

• Solution: Ensure that the hydraulic system is properly calibrated according to the manufacturer’s specifications. This may involve adjusting settings on the pumps, motors, and valves, or recalibrating the machine’s control system.
  

Step-by-Step Troubleshooting for Slow Walking Hydraulics
To effectively diagnose and fix slow walking hydraulics in the CASE CX 135, follow these troubleshooting steps:

1. Check Hydraulic Fluid Levels:
   • Inspect the hydraulic fluid level and condition. If the fluid is low, top it off. If it is contaminated, flush the system and replace the fluid.
     
2. Inspect the Hydraulic Pump:
   • Check the hydraulic pump for any signs of wear, damage, or leakage. If the pump is not functioning properly, repair or replace it.
     
3. Examine Hydraulic Motors:
   • Inspect the hydraulic motors that drive the tracks. Look for any leaks, signs of wear, or unusual noises. If the motors are malfunctioning, they may need to be repaired or replaced.
     
4. Inspect Hydraulic Lines and Filters:
   • Check all hydraulic lines for blockages, cracks, or leaks. Replace any damaged lines and clean or replace hydraulic filters as needed.
     
5. Check Control Valves:
   • Inspect the control valves for damage or blockages. Clean or replace any faulty valves.
     
6. Test the Pressure Relief Valve:
   • Ensure that the hydraulic pressure relief valve is functioning properly. If it is malfunctioning, replace it to restore pressure.
     
7. Calibrate the Hydraulic System:
   • If any components were recently serviced or replaced, ensure that the hydraulic system is properly calibrated according to the manufacturer's specifications.
     

Case Study: Diagnosing Slow Walking Hydraulics on a CASE CX 135
A construction company operating a fleet of CASE CX 135 excavators began noticing slow walking hydraulics in one of their machines. The tracks moved sluggishly, and the operator reported that the excavator was struggling to move efficiently.
Upon inspection, the team discovered that the hydraulic fluid was both low and contaminated. The fluid was replaced with the correct type, and the hydraulic system was flushed. After the fluid replacement, the walking hydraulics performed significantly better. Further inspection revealed a small leak in the hydraulic lines, which was repaired. With the system properly serviced, the machine's walking hydraulics returned to normal.
Conclusion
Slow walking hydraulics in the CASE CX 135 can be caused by a variety of issues, including low hydraulic fluid, worn pumps or motors, and faulty control valves. By systematically troubleshooting the hydraulic system and addressing potential issues such as fluid contamination, leaks, and pressure loss, operators can restore the excavator’s walking hydraulics to optimal performance. Regular maintenance and timely repairs are key to ensuring the longevity and reliability of the hydraulic system, ultimately improving the machine’s efficiency on the job site.