Hitachi EX200-3 Excavator Tracking Fault: Troubleshooting and Solutions

[MikePhua]

The Hitachi EX200-3 is a well-regarded model in the 20-ton class of hydraulic excavators. Known for its reliability and versatility, it is commonly used in construction, mining, and excavation tasks. Despite its robust performance, operators sometimes encounter issues with the tracking system, such as a "weird tracking fault" where the machine's tracks behave erratically or fail to operate smoothly. This article aims to explore the causes of such faults, the diagnostic steps required, and potential solutions to address the issue, ensuring that your Hitachi EX200-3 continues to perform optimally.
Overview of the Hitachi EX200-3 Excavator
The Hitachi EX200-3 is part of Hitachi's EX series, which is known for its powerful hydraulics, smooth operation, and efficiency. Introduced as an upgrade from previous models, the EX200-3 offers a number of key features, including:

• Engine Power: 120 horsepower (approximately 89 kW)
  
• Operating Weight: Around 20,000 kg (44,092 lbs)
  
• Digging Depth: 6.6 meters (21.7 feet)
  
• Bucket Capacity: Approximately 1.0 cubic meters (1.31 cubic yards)
  
• Hydraulic Flow: 210 L/min (55.5 gal/min)
  

With a sturdy undercarriage and impressive digging capabilities, the EX200-3 is used for a variety of applications, including earthmoving, demolition, and material handling. However, like all heavy machinery, it is susceptible to wear and technical faults if not maintained properly.
Tracking System Fault: Causes and Symptoms
A tracking fault, or issues with the tracks not functioning properly, can arise from a variety of sources. The tracks are responsible for transferring the power from the engine to the ground, enabling the machine to move and carry out its tasks. If the tracks are not functioning smoothly, it could affect the overall productivity of the machine.
Here are some common causes of a "weird tracking fault" in the Hitachi EX200-3:

1. Hydraulic System Issues
   The tracking system in the EX200-3 is powered by the hydraulic system, and any issues with the hydraulic components can cause tracking faults. The most common hydraulic-related causes include:
   • Low Hydraulic Fluid: Insufficient hydraulic fluid can lead to reduced pressure, causing the tracks to move slowly or not at all.
     
   • Clogged Filters: Hydraulic filters that are clogged with debris or contaminants can restrict fluid flow, leading to erratic movement of the tracks.
     
   • Hydraulic Pump Failure: A malfunctioning pump can result in low pressure, which affects the efficiency of the tracks.
     
   • Leaking Hydraulic Lines: If there are leaks in the hydraulic lines or fittings, the pressure needed to power the tracks can be lost, leading to movement issues.
     
   Solution: Check the hydraulic fluid levels and replace or top-up if necessary. Inspect and replace hydraulic filters and seals as needed. If the hydraulic pump is found to be faulty, it should be repaired or replaced. A thorough check of the hydraulic system will help identify any leaks or blockages.
   
2. Undercarriage Wear and Tear
   Over time, the undercarriage components such as rollers, sprockets, and idlers can wear down, causing tracking faults. If the tracks are misaligned or too loose, it can lead to poor movement, jerking, or uneven tracking.
   • Excessive Track Slack: If the tracks are too loose, they may slip or fail to engage properly with the sprockets.
     
   • Damaged Track Rollers or Sprockets: Worn or damaged rollers, sprockets, or idlers can cause the track to malfunction or become misaligned.
     
   • Track Tension Issues: Inadequate tension in the tracks, whether too tight or too loose, can lead to poor traction and faulty movement.
     
   Solution: Inspect the track tension regularly and adjust it according to the manufacturer’s guidelines. Check for any signs of wear or damage in the rollers, sprockets, and idlers. If any components are worn out, replace them with genuine parts.
   
3. Electrical or Sensor Malfunctions
   The tracking system in modern excavators like the Hitachi EX200-3 is managed by an integrated electrical control system that communicates with sensors to ensure the tracks function properly. If there are issues with the electrical components, it can lead to the tracks moving incorrectly.
   • Sensor Failures: The EX200-3 uses sensors to monitor track movement and hydraulic pressure. A faulty sensor can send incorrect signals to the control system, causing tracking faults.
     
   • Wiring Issues: Loose or damaged wiring can disrupt communication between the control system and the tracks, leading to erratic movement.
     
   • Control Valve Problems: The control valve regulates the hydraulic flow to the tracks. A malfunction in this component can result in inconsistent power delivery.
     
   Solution: Perform a diagnostic check on the electrical system using the machine’s onboard diagnostic tools. Inspect wiring connections, and check sensors for proper function. If faulty sensors or wiring are detected, repair or replace the necessary parts. The control valve should also be inspected for wear or failure.
   
4. Transmission Problems
   The transmission system is another important aspect of the track system. Transmission issues can cause uneven or jerky track movement. Problems in the transmission can affect the transfer of power from the engine to the tracks, resulting in tracking faults.
   • Clutch Issues: If the clutch mechanism is malfunctioning, it may not properly engage the track drive system, leading to slippage or jerky movement.
     
   • Transmission Fluid Problems: Low or dirty transmission fluid can cause transmission parts to wear out, resulting in power loss and erratic track movement.
     
   Solution: Check the transmission fluid levels and condition. If the fluid is low or contaminated, replace it with the manufacturer-recommended fluid. Have the clutch system and other transmission components inspected and repaired if necessary.
   
5. Control System Malfunction
   The control system is responsible for coordinating the operation of the tracks. If the control system is malfunctioning, it can cause erratic or unpredictable movement of the tracks.
   • Calibration Issues: The control system may need recalibration to ensure it is sending the correct signals to the track drive system.
     
   • Software Problems: In modern excavators, software issues can also contribute to tracking faults.
     
   Solution: Recalibrate the control system to ensure proper track alignment and movement. Perform a software diagnostic to identify any programming or sensor issues that might be causing the fault.
   

Steps to Diagnose and Fix the Tracking Fault

1. Check Hydraulic Fluid Levels and Condition: Start by inspecting the hydraulic fluid levels and ensuring they are at the proper levels. If the fluid is contaminated or low, replace or top it up with the correct type.
   
2. Inspect the Undercarriage: Check for any damage or wear in the track rollers, sprockets, idlers, and tracks. Adjust track tension as needed and replace any worn components.
   
3. Perform an Electrical Check: Use the machine’s diagnostic system to check for errors or faults in the electrical components. Inspect wiring, sensors, and control valves for any issues.
   
4. Test the Transmission: Check the transmission fluid and inspect for any signs of contamination or low fluid levels. Have the clutch and transmission components tested for proper function.
   
5. Recalibrate the Control System: If all mechanical issues are addressed and the fault persists, recalibrate the control system and ensure all software is up to date.
   

Preventive Measures
To avoid future tracking issues with the Hitachi EX200-3, operators should follow these preventive measures:

• Regular Maintenance: Perform routine checks on the hydraulic system, undercarriage, and transmission. Replace filters and fluids as per the manufacturer’s guidelines.
  
• Track Inspections: Regularly inspect the tracks and undercarriage for signs of wear. Keep the tracks clean and well-maintained to prevent unnecessary wear and tear.
  
• Monitor the Hydraulic System: Keep a close eye on the hydraulic pressure and fluid levels to ensure the system is functioning properly.
  

Conclusion
Tracking faults in the Hitachi EX200-3 excavator can stem from a variety of issues, including hydraulic system problems, undercarriage wear, electrical malfunctions, and transmission issues. A systematic approach to diagnosis, along with preventive maintenance, can help mitigate the risk of these problems and ensure the excavator operates smoothly. By staying on top of maintenance and addressing faults early, operators can maximize the lifespan and productivity of their Hitachi EX200-3, keeping it in optimal working condition for demanding tasks.