Hitachi Pump Kicks Off: Troubleshooting and Solutions

[MikePhua]

Introduction
When working with Hitachi machinery, one of the common issues that operators might encounter is the hydraulic pump kicking off. This can disrupt operations and lead to potential delays in work. Understanding the causes and how to troubleshoot the problem is essential to maintaining the efficiency and reliability of the machine. This article will explore the possible reasons behind the issue, along with troubleshooting steps and solutions to help you address the problem effectively.
1. Possible Causes of the Hydraulic Pump Kicking Off
Several factors could cause a hydraulic pump in a Hitachi machine to kick off. Here are some of the most common reasons:

• Low Hydraulic Fluid Levels: One of the most straightforward causes for a hydraulic pump to stop functioning is low hydraulic fluid levels. If the fluid is insufficient, the pump may struggle to maintain pressure, leading it to shut off as a protective measure.
  
• Contaminated Hydraulic Fluid: Dirty or contaminated hydraulic fluid can clog filters and valves, impairing the pump’s functionality. The buildup of debris in the fluid can cause erratic pump behavior, including it kicking off during operation.
  
• Faulty Pressure Relief Valve: The pressure relief valve is designed to release excess pressure from the system. If the valve is malfunctioning or set incorrectly, it can cause the hydraulic pump to engage and disengage unexpectedly.
  
• Air in the Hydraulic System: Air trapped in the hydraulic lines can lead to inconsistent pump performance. The air disrupts the flow of fluid, reducing the pump’s ability to maintain steady pressure, which can cause it to kick off.
  
• Pump Wear or Damage: Over time, the hydraulic pump itself can wear out or become damaged. Components such as seals, bearings, and internal parts can degrade, causing the pump to underperform or fail to operate consistently.
  
• Electrical or Sensor Issues: On some models, electrical or sensor issues can lead to improper communication with the hydraulic system, causing the pump to kick off. These problems could be linked to wiring, sensors, or control modules.
  

2. Troubleshooting Steps to Identify the Problem
To diagnose the issue, follow these steps:

• Check Hydraulic Fluid Levels: Always start by inspecting the hydraulic fluid levels. If they are low, add the recommended type of fluid and check for any leaks in the system. Keep in mind that using the correct fluid type is crucial for optimal performance.
  
• Examine Fluid Condition: If the fluid appears dirty or contains visible debris, it’s essential to flush the system and replace the fluid. Regularly check the fluid’s color and consistency to ensure it remains clean.
  
• Inspect the Pressure Relief Valve: Ensure the pressure relief valve is working correctly and is set to the appropriate pressure. If the valve is damaged, it may need to be replaced or repaired.
  
• Bleed the System: If air is suspected in the system, bleed the hydraulic lines to remove any trapped air. You can do this by following the manufacturer’s instructions for your specific machine.
  
• Inspect the Hydraulic Pump: Look for signs of wear or damage to the pump. If any components appear worn, consider having the pump rebuilt or replaced. It is important to ensure all seals and components are intact.
  
• Check Electrical and Sensor Connections: Inspect the electrical wiring and sensor connections that control the hydraulic pump. Look for loose connections, faulty sensors, or damaged wiring, and replace or repair them as necessary.
  

3. Solutions for Resolving the Hydraulic Pump Issue
Once you have identified the cause of the hydraulic pump kicking off, the following solutions can help resolve the problem:

• Top Off Hydraulic Fluid: If the issue was caused by low fluid levels, simply topping off the hydraulic fluid may resolve the problem. However, if you continuously find low levels, investigate for leaks and fix them.
  
• Flush and Replace Contaminated Fluid: If the fluid is contaminated, flush the hydraulic system thoroughly and replace the fluid with the recommended type. Be sure to clean or replace any filters that might have been clogged by the debris.
  
• Repair or Replace the Pressure Relief Valve: If the pressure relief valve is faulty, it may need to be cleaned, repaired, or replaced. Ensure it is correctly calibrated to the machine’s operating pressure.
  
• Bleed the System Properly: Air trapped in the system can often be eliminated by following the proper bleeding procedure. Once the air is out, the hydraulic pump should function more reliably.
  
• Pump Replacement or Repair: In cases where the pump itself is worn or damaged, it will likely need to be replaced. If the pump is still under warranty, contact the manufacturer for a replacement. Otherwise, have a professional technician perform a pump overhaul or replacement.
  
• Fix Electrical or Sensor Issues: Repair any damaged wiring, faulty sensors, or malfunctioning control modules. Ensure all electrical connections are secure, and that sensors are providing accurate readings to the pump’s control system.
  

4. Preventive Maintenance to Avoid Future Issues
To prevent the hydraulic pump from kicking off in the future, follow these preventive maintenance steps:

• Regularly Check Hydraulic Fluid: Periodically check the fluid levels and condition. Change the fluid and replace filters as recommended by the manufacturer to maintain system cleanliness.
  
• Inspect the Pump and Valves: Regularly inspect the pump, pressure relief valve, and other critical components for wear and tear. Perform early repairs to prevent larger issues.
  
• Bleed the System: Ensure the hydraulic system is bled when necessary, especially if the machine is exposed to extreme conditions or if the hydraulic lines are opened for repairs.
  
• Monitor Machine Performance: Keep an eye on machine performance, including the hydraulic pump’s operation. Any irregular sounds, vibrations, or warning lights should be addressed promptly to avoid major breakdowns.
  

Conclusion
A hydraulic pump kicking off in a Hitachi machine can be a sign of several potential issues, ranging from low hydraulic fluid to pump wear. By carefully diagnosing the problem and addressing the underlying cause, you can restore optimal performance to your machine. Regular maintenance, including fluid checks and pump inspections, will help minimize the risk of this issue occurring in the future. If in doubt, consult with a qualified technician to ensure that all components are functioning properly and to avoid unnecessary repairs.