Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Hitachi 120-5 Hydraulic Pump Issues and Discussion Summary
#1
The Hitachi 120-5 is a commonly used mid-sized excavator in various construction projects. Its hydraulic pump plays a crucial role in transferring power to the hydraulic system, ensuring smooth operation of the machine's functions. Recently, users have discussed several issues with the hydraulic pump, such as reduced hydraulic performance and pump failure. This article summarizes these problems and the suggested solutions.
Common Issues
  • Low Hydraulic System Pressure
    Some users have reported issues with low hydraulic pressure, leading to sluggish operation or a reduction in machine functionality. This is typically linked to a decline in the hydraulic pump's performance or contamination of the hydraulic oil. Dirty or aged hydraulic oil can increase friction inside the pump, reducing its efficiency and performance.
  • Pump Damage and Leaks
    Another common problem is pump damage or oil leaks. Prolonged heavy-duty operation or poor-quality hydraulic oil can cause the pump components to degrade, resulting in seal failure and oil leakage. If not addressed promptly, this can prevent the hydraulic system from maintaining proper pressure, affecting the machine's overall performance.
  • Overheating Issues
    Users have also noted that the hydraulic pump tends to overheat. This is often caused by increased internal resistance, which forces the pump to work harder. Overheating can not only reduce the pump's efficiency but also cause damage to the pump itself and other vital components.
Maintenance and Care Recommendations
  • Regular Inspection of Hydraulic Oil Quality
    The cleanliness and quality of hydraulic oil are critical to the lifespan of the hydraulic pump. It is recommended to change the hydraulic oil regularly and use suitable filters to maintain oil cleanliness. Using high-quality hydraulic oil and ensuring it stays within the recommended temperature range are key to keeping the hydraulic system running smoothly.
  • Monitoring Pump Performance
    Regularly checking the hydraulic pump's pressure, temperature, and operational sound can help detect issues early. If any pressure fluctuations or abnormal sounds are noticed, it is important to check the hydraulic pump and associated hoses to prevent further damage.
  • Replacing Seals and Components Regularly
    The seals in the hydraulic pump can wear out or degrade over time due to prolonged exposure to high temperatures and pressures. It is advised to regularly inspect and replace the seals to avoid oil leaks and ensure smooth operation of the pump.
Pump Replacement and Repair
Due to the high cost of hydraulic pumps, many users opt for either purchasing a second-hand pump or repairing the existing one. When repairing, it is crucial to ensure that all components meet the required standards to prevent further complications. In cases where the pump is severely damaged, replacing it with either an original or compatible alternative is recommended to avoid compatibility issues.
Conclusion
Common issues with the Hitachi 120-5 hydraulic pump include low pressure, pump damage, and overheating. Regular oil changes, pump maintenance, and seal inspections can help extend the lifespan of the hydraulic pump. Timely attention to any abnormalities can prevent further damage, ensuring the excavator operates efficiently and reliably.
Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  Hitachi's Equivalent to the CAT 365B Excavator MikePhua 0 1 24 minutes ago
Last Post: MikePhua
  Hitachi EX200-2 Excavator MikePhua 0 3 Yesterday, 10:36 PM
Last Post: MikePhua
  Caterpillar M310MY Hydraulic Hose Routing Explained MikePhua 0 1 Yesterday, 10:26 PM
Last Post: MikePhua
  Hydraulic Pump Flow and Identification Challenges on Kalmar DRD420-60S5 Reach Stackers MikePhua 0 1 Yesterday, 08:18 PM
Last Post: MikePhua
  Hitachi EX35-2: A Compact Workhorse for Urban Excavation MikePhua 0 1 Yesterday, 07:12 PM
Last Post: MikePhua
  Pettibone Multikranes: Pioneers in Mobile Hydraulic Cranes MikePhua 0 3 Yesterday, 02:02 AM
Last Post: MikePhua
  Hitachi EX150 Battery Relay Wiring Explained MikePhua 0 3 Yesterday, 01:39 AM
Last Post: MikePhua
  Evaluating the CAT 307SSR Excavator and Its Hydraulic Limitations MikePhua 0 5 08-28-2025, 03:35 PM
Last Post: MikePhua
  Hitachi EX100-2 Excavator Legacy and Electrical System Insights MikePhua 0 6 08-28-2025, 02:30 PM
Last Post: MikePhua
  Hitachi 670 Excavator Overview MikePhua 0 7 08-27-2025, 08:06 PM
Last Post: MikePhua
  What Is the Function of the Hydraulic Block and Relief System on the Case 1845C Skid Steer MikePhua 0 6 08-27-2025, 04:19 PM
Last Post: MikePhua
  Case 580SM Hydraulic Tank Overview and Related Specifications MikePhua 0 9 08-27-2025, 03:38 PM
Last Post: MikePhua
  Komatsu PC200LC-7 Hydraulic Excavator Detailed Overview MikePhua 0 9 08-27-2025, 03:19 PM
Last Post: MikePhua
  Hitachi EX60-1 Manual Essentials MikePhua 0 7 08-27-2025, 01:46 PM
Last Post: MikePhua
  Scat Trak Mini Excavator Hydraulic Controls and Operation MikePhua 0 8 08-27-2025, 04:13 AM
Last Post: MikePhua

Forum Jump:


Users browsing this thread: