Troubleshooting the Hitachi EX200 LC Hydraulic Problem: Stalling Engine Solutions

[MikePhua]

When working with heavy equipment like the Hitachi EX200 LC, one of the most frustrating issues that operators can face is the engine stalling due to hydraulic system problems. This problem can significantly disrupt the workflow and even lead to costly downtime if not diagnosed and resolved quickly. In this article, we’ll explore the common causes of hydraulic-related engine stalling issues on the Hitachi EX200 LC and how to address them effectively, drawing on real-world insights and solutions.
Understanding the Problem: Hydraulic System Impact on Engine Performance
The hydraulic system in any excavator plays a crucial role in powering various functions, such as boom and bucket movement. On the Hitachi EX200 LC, if there’s an issue within the hydraulic system, it can lead to a decrease in engine performance, ultimately resulting in the engine stalling. This problem is usually a symptom of an underlying hydraulic issue that requires attention.
Common Causes of Hydraulic-Related Engine Stalling on the Hitachi EX200 LC
There are several potential causes that could lead to the engine stalling while operating the hydraulic system. Understanding these common causes is essential for quick troubleshooting:
1. Low Hydraulic Oil Levels or Contaminated Oil
One of the first things to check is the hydraulic oil levels. If the oil is too low, it could lead to the hydraulic pump failing to function properly, which in turn could cause the engine to stall under load. Additionally, if the oil is contaminated or too thick, it can result in poor hydraulic performance and system strain, leading to stalling.
Solution:

• Check hydraulic oil levels: Always ensure that the hydraulic oil is filled to the manufacturer’s recommended levels. If it’s too low, top it up using the appropriate oil.
  
• Inspect oil quality: Look for any signs of contamination such as discoloration or a milky appearance. If contamination is found, perform an oil change and replace any filters.
  
• Use the correct oil: Make sure you’re using the right type of hydraulic oil, as recommended in the operator’s manual. Using the wrong oil can lead to clogging or pump issues.
  

2. Faulty Hydraulic Pump or Pump Pressure Issues
The hydraulic pump is responsible for circulating fluid throughout the system, and if it fails or operates at the wrong pressure, it can lead to a stall in engine performance. A weak pump or damaged pump seals can cause the hydraulic fluid to bypass, leading to a lack of hydraulic power and stalling.
Solution:

• Test the pump pressure: Check the hydraulic pressure levels to ensure they’re within the correct range. Low pressure can be indicative of a failing pump or an issue with the pump’s control valve.
  
• Inspect the pump: If there is an issue with the pump, such as wear or a damaged seal, it may need to be repaired or replaced.
  
• Perform a hydraulic flow test: This will help you confirm whether the pump is providing the necessary fluid flow to the system.
  

3. Clogged Hydraulic Filters or Lines
Hydraulic filters are crucial for keeping debris and contaminants out of the system. If the filter becomes clogged, it can cause the hydraulic oil to flow improperly, leading to increased pressure and possibly stalling the engine. Similarly, if there are any blockages in the hydraulic lines, fluid flow will be restricted, causing the engine to strain and potentially stall.
Solution:

• Replace the hydraulic filter: If the filter is dirty or clogged, it can significantly reduce the system’s efficiency. Replace it regularly as part of the preventive maintenance schedule.
  
• Check hydraulic lines: Inspect the hydraulic lines for any blockages or leaks. Clean or replace any damaged hoses to restore normal fluid flow.
  

4. Air in the Hydraulic System
Air in the hydraulic system can lead to a decrease in hydraulic efficiency. This can cause issues with fluid flow, resulting in erratic movement of the excavator’s arms and a potential engine stall. Air can enter the system through a number of different routes, such as a loose connection or a leak in the lines.
Solution:

• Bleed the system: If you suspect air is trapped in the system, it’s important to bleed the lines to remove the air pockets. This can be done by loosening fittings and allowing fluid to flow freely until no air is present.
  
• Check for leaks: Inspect the system for any leaks where air might be entering, and repair any cracked or loose fittings.
  

5. Faulty Hydraulic Relief Valve
The hydraulic relief valve is responsible for protecting the system from excessive pressure. If this valve is malfunctioning, it could cause the hydraulic system to work under extreme pressure, which can result in engine stalling as the system struggles to function. This is particularly common if the valve becomes stuck or is not properly calibrated.
Solution:

• Inspect the relief valve: Check the hydraulic relief valve for proper operation. If the valve is stuck or damaged, it will need to be replaced.
  
• Calibrate the relief valve: Ensure that the valve is set to the correct pressure range as outlined in the operator’s manual.
  

Additional Troubleshooting Tips
Beyond checking the hydraulic system, there are a few other areas to consider when diagnosing engine stalling issues on the Hitachi EX200 LC:

• Check the engine for any performance issues: Ensure that the engine is functioning properly and that there are no fuel, electrical, or exhaust problems contributing to the stall.
  
• Monitor the temperature: Overheating of the hydraulic system or the engine can also lead to stalling. Check for adequate coolant levels and inspect the radiator for any obstructions.
  
• Regular maintenance: Keeping up with regular service intervals, such as changing oil and filters, will ensure that the system operates smoothly and can help prevent issues from arising.
  

Conclusion: Preventing Hydraulic Stalling on the Hitachi EX200 LC
Dealing with a stalling engine on the Hitachi EX200 LC can be frustrating, but by understanding the common causes and implementing effective troubleshooting methods, most problems can be resolved. Regular maintenance, careful inspection of the hydraulic system, and prompt attention to any issues will ensure that your excavator remains in top working condition and avoid costly downtime.
By addressing hydraulic system problems such as low oil levels, faulty pumps, and clogged filters, operators can ensure that the EX200 LC performs at its best, even under demanding conditions.