Troubleshooting Power Loss Under Load in Sumitomo SH210-5 Excavator

[MikePhua]

The Sumitomo SH210-5 is a widely used hydraulic excavator known for its durability, performance, and versatility across various industries like construction, mining, and heavy lifting. However, like all heavy machinery, it can experience operational issues over time. One common problem that many operators face is a loss of power under load. This issue can be frustrating and may lead to decreased efficiency and productivity if not addressed properly. In this article, we will explore the potential causes of this power loss, provide troubleshooting steps, and offer solutions to ensure the excavator performs at its best.
Understanding the Problem: Power Loss Under Load
When an excavator like the Sumitomo SH210-5 loses power under load, it means that the engine is unable to provide the necessary power to meet the demands of the hydraulic system or the drive system. This can be particularly noticeable when the machine is lifting, digging, or performing tasks that require high engine performance. The power loss may manifest as reduced digging force, slower cycle times, or the engine struggling to maintain speed, even with the throttle fully engaged.
Common Causes of Power Loss Under Load
Several factors can contribute to a loss of power under load in the Sumitomo SH210-5 excavator. Understanding these potential causes is the first step toward diagnosing and fixing the issue.

1. Fuel System Problems
   The fuel system plays a crucial role in delivering the necessary energy to the engine. A problem in the fuel system can lead to inadequate fuel delivery, causing the engine to lose power when under load.
   • Clogged Fuel Filters: Over time, fuel filters can become clogged with dirt, debris, or contaminants from the fuel. When the filters are clogged, the engine may not receive the proper amount of fuel, leading to power loss under load.
     
   • Fuel Pump Issues: A malfunctioning fuel pump can fail to deliver the required fuel pressure to the engine, causing a power deficit during heavy operation.
     
   • Air in the Fuel Lines: If air enters the fuel system, it can cause fuel starvation, leading to power loss under load.
     
2. Hydraulic System Problems
   The hydraulic system in an excavator is responsible for transmitting power from the engine to the various hydraulic components (such as the boom, arm, and bucket). Hydraulic issues can result in power loss when the system is under heavy load.
   • Low Hydraulic Fluid Levels: Insufficient hydraulic fluid can cause the hydraulic pump to work harder to move fluid, leading to a drop in performance and power. This can also cause overheating, which can exacerbate the power loss issue.
     
   • Hydraulic Pump Failure: If the hydraulic pump is not functioning properly, the excavator may experience poor hydraulic performance, which affects its overall power output under load.
     
   • Clogged Hydraulic Filters: Just like the fuel system, the hydraulic system has filters that can become clogged over time. If the filters are blocked, it can cause a drop in fluid flow, leading to power loss.
     
   • Internal Hydraulic Leaks: Internal leaks within the hydraulic system can reduce the efficiency of fluid distribution, further contributing to power loss.
     
3. Engine Issues
   Engine performance is a direct factor in the power output of any excavator. If there are issues with the engine, the excavator may lose power under load.
   • Turbocharger Problems: The turbocharger in the engine boosts the intake air pressure to improve combustion efficiency. A malfunctioning turbocharger can lead to reduced air intake, causing a loss of engine power.
     
   • Low Compression: Over time, the engine’s compression can decrease due to wear and tear on the pistons, rings, or cylinder heads. Low compression results in inefficient combustion, leading to power loss under load.
     
   • Faulty Injectors: If the fuel injectors are clogged or malfunctioning, they may not deliver the correct amount of fuel into the combustion chamber, leading to incomplete combustion and reduced power output.
     
4. Transmission and Drive System Problems
   The transmission system transfers power from the engine to the tracks or wheels, and any issues here can cause the excavator to lose power when under load.
   • Transmission Fluid Issues: Low or contaminated transmission fluid can cause the transmission to slip or not function optimally, leading to power loss under load.
     
   • Clutch or Gear Problems: Worn-out clutches or damaged gears can affect the transfer of power from the engine to the drivetrain, causing reduced efficiency and power during operation.
     
   • Drive Motor Failures: Problems with the drive motor, including internal failures or fluid leaks, can reduce the efficiency of power transfer from the engine to the tracks, leading to performance issues under load.
     
5. Excessive Engine Temperature
   Overheating can significantly impact the performance of any engine. If the engine temperature rises too high, it can lead to a loss of power, as the engine may reduce its performance to avoid further damage.
   • Radiator Problems: A clogged or malfunctioning radiator can cause the engine to overheat, which may lead to a decrease in power output.
     
   • Cooling System Issues: Problems with the coolant pump, hoses, or thermostat can prevent the engine from staying at the optimal operating temperature, leading to overheating and power loss.
     
6. Electrical System Problems
   The electrical system of the excavator plays a critical role in maintaining engine performance. A fault in the electrical system can disrupt engine function, leading to power loss under load.
   • Weak Battery or Alternator: A weak battery or faulty alternator can prevent the engine from getting the proper voltage it needs to operate efficiently, leading to power issues under load.
     
   • Sensor Malfunctions: Modern excavators rely on various sensors to monitor engine and hydraulic system performance. A malfunction in any of these sensors can cause the engine or system to run inefficiently, leading to power loss.
     

Troubleshooting and Solutions
Now that we understand the potential causes of power loss under load in the Sumitomo SH210-5, let's look at the steps you can take to troubleshoot and resolve the issue:

1. Check the Fuel System
   • Inspect the fuel filters for clogs and replace them if necessary.
     
   • Check the fuel pump for proper operation and fuel pressure.
     
   • Ensure there is no air in the fuel lines by checking for leaks or loose connections.
     
2. Inspect the Hydraulic System
   • Check the hydraulic fluid levels and top up if necessary.
     
   • Inspect the hydraulic pump for signs of damage or wear.
     
   • Replace any clogged hydraulic filters and check for leaks in the hydraulic lines.
     
3. Engine Diagnostics
   • Inspect the turbocharger and ensure it is functioning properly. Listen for any unusual noises or a lack of boost pressure.
     
   • Perform a compression test on the engine to check for any internal wear or damage.
     
   • Inspect the fuel injectors for clogs or malfunctions and clean or replace them as needed.
     
4. Transmission and Drive System Checks
   • Check the transmission fluid for the correct level and condition. Replace or top up as necessary.
     
   • Inspect the clutch and gear system for any signs of wear or damage.
     
   • Check the drive motor and related components for leaks or failures.
     
5. Check the Cooling System
   • Inspect the radiator for blockages or leaks and clean it if necessary.
     
   • Check the coolant level and replace the coolant if it appears dirty or contaminated.
     
   • Ensure that the cooling system components, such as the pump and thermostat, are functioning correctly.
     
6. Electrical System Inspection
   • Test the battery and alternator to ensure they are providing adequate voltage.
     
   • Inspect the sensors and wiring for any faults or damage.
     

Preventive Maintenance Tips
To prevent future power loss issues, consider the following preventive maintenance practices:

• Regularly check and change fuel and hydraulic filters.
  
• Monitor fuel levels and quality to avoid air contamination in the system.
  
• Perform routine engine diagnostics and compression checks.
  
• Keep the cooling system clean and free of debris.
  
• Inspect the electrical system periodically for faults or weak components.
  

Conclusion
Power loss under load in the Sumitomo SH210-5 excavator can be caused by a variety of factors, including issues with the fuel system, hydraulic system, engine, transmission, or electrical components. Identifying and addressing the root cause of the problem is crucial for restoring the excavator’s performance and ensuring it operates efficiently in demanding environments. By following a systematic troubleshooting process and conducting regular maintenance, you can minimize downtime and maximize the lifespan of your equipment.