Hitachi EX120-2 Hydraulic Conversion Kit Installation

[MikePhua]

Introduction
The Hitachi EX120-2 excavator, a staple in the construction industry, has undergone various modifications to enhance its performance and adaptability. One significant upgrade is the hydraulic conversion kit, which replaces the original electric control system with a manual hydraulic setup. This modification aims to improve reliability and reduce maintenance costs.
Understanding the Hydraulic Conversion Kit
The hydraulic conversion kit for the EX120-2 includes several key components:

• Control Valve: Directs hydraulic fluid to various parts of the excavator.
  
• Flow Controller: Regulates the flow of hydraulic fluid to ensure consistent performance.
  
• Fittings and Hoses: Connects the hydraulic components, allowing fluid transfer.
  
• O-Rings and Seals: Prevents leaks and ensures the integrity of the hydraulic system.
  

Installation Process
Installing the hydraulic conversion kit involves several steps:

1. Disassemble the Control Valve: Remove the existing electric components and prepare the control valve for the new hydraulic fittings.
   
2. Assemble the Flow Controller: Install O-rings, springs, and select the appropriate shims and plugs based on the engine type.
   
3. Modify the Pump: Remove certain parts from the pump and add O-rings before mounting the flow controller assembly.
   
4. Install Fittings and Hoses: Connect the hydraulic lines to the control valve and other components, ensuring all connections are secure.
   
5. Test the System: After installation, test the hydraulic system to ensure proper operation and check for any leaks.
   

Considerations and Tips

• Compatibility: Ensure that the conversion kit is compatible with the EX120-2 model. Some kits are also applicable to EX100-2/3 and EX200-2/3 models.
  
• Professional Assistance: If unsure about the installation process, consider seeking assistance from a professional mechanic familiar with hydraulic systems.
  
• Regular Maintenance: After installation, regular maintenance is crucial to ensure the longevity and efficiency of the hydraulic system.
  

Conclusion
The hydraulic conversion kit for the Hitachi EX120-2 excavator offers improved reliability and performance. By understanding the components and installation process, operators can successfully upgrade their machines to meet modern demands. Regular maintenance and professional assistance, when necessary, will ensure the continued success of this modification.