Comprehensive Guide to Troubleshooting Steering Issues in the Volvo L220E Wheel Loader

[MikePhua]

The Volvo L220E wheel loader is renowned for its robust performance and advanced hydraulic steering system. However, operators may occasionally encounter steering problems that can impede productivity. This guide delves into common steering issues, diagnostic procedures, and maintenance practices to ensure optimal performance of the steering system.

Understanding the Steering System
The L220E is equipped with a load-sensing hydrostatic steering system that activates only when the steering wheel is turned, thereby conserving energy and reducing fuel consumption. This system comprises several key components:

• Steering Valve (Orbitrol Valve): Directs hydraulic fluid to the steering cylinders based on operator input.
  
• Steering Cylinders: Convert hydraulic pressure into mechanical force to turn the wheels.
  
• Hydraulic Pump: Supplies pressurized fluid to the steering system.
  
• Load Sensing System (LS): Monitors steering pressure and adjusts flow to maintain consistent performance.
  
• Pressure Relief Valve: Protects the system from excessive pressure that could cause damage.
  

Common Steering Issues and Diagnostics

1. Intermittent Steering Loss
   Operators have reported instances where the steering wheel becomes unresponsive after quick or jerky movements, only to regain functionality after a brief pause. This issue often points to:
   • Pressure Drop: A significant drop in steering pressure from 3050 psi to 150 psi when the problem occurs.
     
   • Load Sensing Line Blockage: A drop in LS pressure from 40 psi to 0 psi during the fault condition.
     
   • Possible Causes: Contaminated or faulty steering valve, malfunctioning pressure relief valve, or issues within the load sensing system.
     
   Diagnostic steps include inspecting the steering valve for debris, testing the pressure relief valve, and ensuring the LS system is free from obstructions.
   
2. Complete Steering Failure
   In more severe cases, the steering wheel may become completely unresponsive, and the machine may be unable to turn. This can result from:
   • Hydraulic Fluid Contamination: Debris or water in the hydraulic fluid can cause internal component wear or blockages.
     
   • Worn Steering Cylinders: Damaged or leaking cylinders can lead to a loss of steering force.
     
   • Faulty Hydraulic Pump: A malfunctioning pump may not provide adequate pressure to the steering system.
     
   It's crucial to check the hydraulic fluid quality, inspect cylinders for leaks, and test the pump's output pressure.
   

Maintenance Practices to Prevent Steering Issues

• Regular Fluid Checks: Monitor hydraulic fluid levels and quality. Low or contaminated fluid can impair steering performance.
  
• System Flushing: Periodically flush the hydraulic system to remove contaminants and prevent blockages.
  
• Component Inspections: Regularly inspect the steering valve, cylinders, and hydraulic lines for signs of wear or damage.
  
• Pressure Testing: Use pressure gauges to verify that the system maintains the correct operating pressures.
  

Case Study: Resolving Steering Issues in a Volvo L220E
A fleet operator in New Zealand reported intermittent steering loss in their L220E loader. After ruling out the steering valve and shift valve, they adjusted the steering pressure to 3050 psi. Initially, the steering functioned correctly, but during a test drive, the steering failed again. Upon further investigation, they discovered a significant drop in LS pressure, indicating a blockage or malfunction in the LS system. Clearing the obstruction restored normal steering function.

Conclusion
Steering issues in the Volvo L220E wheel loader can stem from various sources, including hydraulic pressure problems, component wear, and system blockages. By understanding the system's components and implementing regular maintenance practices, operators can minimize downtime and ensure the loader's optimal performance. Always consult the manufacturer's service manual for detailed procedures and specifications.