Hitachi EX120-1 Excavator Common Issues and Solutions

[MikePhua]

Introduction
The Hitachi EX120-1 excavator is a heavy-duty machine widely used in construction and excavation projects due to its reliable performance and efficiency. However, like any machine, users may experience some common issues. This article discusses a few of these issues and provides troubleshooting advice to help users maintain their machine in optimal working condition.
Engine Starting Issues
One common problem faced by EX120-1 owners is difficulty starting the engine. Possible causes of this issue include:

• Insufficient or old battery power
  
• Starter motor failure
  
• Fuel system issues, such as clogged fuel filters or a malfunctioning fuel pump
  

Solution:

• Check the battery voltage and condition. If the battery is old or has low charge, it should be replaced.
  
• Inspect the starter motor and electrical system to ensure all connections are secure and the starter motor is functioning properly.
  
• Check the fuel filter and fuel lines for blockages or damage. Clean or replace the filter if necessary.
  

Hydraulic System Problems
Another common issue for the EX120-1 excavator is poor hydraulic performance, such as slow or unstable hydraulic movements. The possible causes of this issue include:

• Low hydraulic fluid levels or degraded fluid
  
• Hydraulic pump or valve failure
  
• Leaks in hydraulic hoses or connections
  

Solution:

• Regularly check the hydraulic fluid levels and ensure that the fluid meets specifications. If the fluid is dirty or degraded, replace it.
  
• Inspect the hydraulic pump, valves, and connection points for leaks. Repair or replace damaged components as needed.
  
• Check the hydraulic hoses and connections for any leaks. Replace or repair damaged hoses or fittings.
  

Travel System Failures
Some users report issues with the travel system of their EX120-1 excavator, such as the machine failing to travel or moving erratically. Potential causes of this issue include:

• Travel motor failure
  
• Problems with the travel hydraulic system
  
• Electrical faults in the control system
  

Solution:

• Inspect the travel motor to ensure it is operating correctly. If the motor is damaged, it may need to be replaced.
  
• Check the travel hydraulic system, including the hydraulic motors and drive shafts, to ensure there are no leaks and that the hydraulic pressure is normal.
  
• Inspect the control system to ensure all electrical connections are secure and there are no shorts or faults.
  

Overheating Issues
Overheating is a common problem for excavators that are used for extended periods of high-load work, and the EX120-1 is no exception. The potential causes of overheating include:

• Clogged cooling system
  
• Low coolant levels or poor-quality coolant
  
• Engine overload
  

Solution:

• Regularly inspect the radiator and cooling system for blockages. Clean the radiator and cooling fan to ensure proper airflow.
  
• Check the coolant levels and ensure the coolant meets the required specifications. Replace the coolant if it is degraded.
  
• Reduce the machine's workload to avoid excessive engine strain and maintain the engine within its normal operating temperature.
  

Conclusion
The Hitachi EX120-1 excavator is a highly efficient and reliable machine, but like all heavy machinery, it may encounter common issues over time. Through regular inspections and maintenance, users can quickly identify and resolve issues related to the hydraulic system, engine, and travel system, prolonging the lifespan of the machine and enhancing its efficiency. Operators and maintenance personnel are encouraged to follow the manufacturer's guidelines for routine maintenance and seek professional assistance when encountering more complex issues.