Link-Belt LS-2650 Starting Issues: Diagnosis and Solutions

[MikePhua]

The Link-Belt LS-2650, a hydraulic crawler excavator, has been a reliable machine for many operators. However, some users have reported intermittent starting problems, particularly with the Isuzu engine. These issues often manifest as the engine turning over but failing to start, or requiring starting fluid to initiate operation.
Common Symptoms

• Cold Start Difficulty: The engine struggles to start in cold conditions but may start with the aid of starting fluid.
  
• Intermittent Starting: The machine may start after several attempts or after a period of downtime.
  
• Engine Bogging: Under load, the engine may bog down or stall, indicating potential fuel delivery issues.
  

Potential Causes

1. Fuel System Contamination: Over time, debris can accumulate in the fuel system, leading to clogs. The Isuzu engine's fuel system includes strainers in the banjo bolts at the filter housing and lift pump inlet. These strainers can become clogged, restricting fuel flow and causing starting issues. Regular inspection and cleaning of these components are essential.
   
2. Fuel Pressure Issues: Inconsistent fuel pressure can lead to poor engine performance. While some operators have reported that fuel pressure readings appear normal, fluctuations in pressure can still cause starting problems. It's advisable to check for any pressure drops or inconsistencies during startup attempts.
   
3. Injection Pump Malfunction: The injection pump plays a crucial role in delivering fuel to the engine. If the pump is malfunctioning or has worn components, it may not deliver fuel at the correct timing or volume, leading to starting difficulties. Regular maintenance and timely replacement of the pump can prevent such issues.
   
4. Electrical System Faults: Electrical issues, such as faulty relays, sensors, or wiring, can disrupt the operation of the fuel system and other critical components. Inspecting the electrical system for any signs of wear or damage can help identify potential problems.
   

Diagnostic Steps

• Inspect Fuel Filters and Strainers: Check and clean the fuel filters and strainers to ensure unobstructed fuel flow.
  
• Monitor Fuel Pressure: Use a fuel pressure gauge to monitor pressure during startup attempts. Look for any drops or inconsistencies.
  
• Test Injection Pump: Have the injection pump tested for proper operation and replace it if necessary.
  
• Check Electrical Components: Inspect relays, sensors, and wiring for any signs of damage or malfunction.
  

Maintenance Recommendations

• Regular Cleaning: Periodically clean the fuel system components to prevent debris buildup.
  
• Scheduled Replacements: Replace fuel filters and strainers at recommended intervals.
  
• Electrical System Checks: Regularly inspect the electrical system to ensure all components are functioning correctly.
  

By following these diagnostic steps and maintenance recommendations, operators can address and prevent starting issues with the Link-Belt LS-2650, ensuring reliable performance and longevity of the machine.