Comprehensive Troubleshooting and Maintenance Guide for JLG Equipment

[MikePhua]

Overview of JLG Equipment
JLG Industries is a leading manufacturer of aerial work platforms, telehandlers, and other construction access equipment. Their machines are renowned for reliability but require proper maintenance and troubleshooting to ensure continued safe operation.
Common Issues Encountered in JLG Equipment

• Hydraulic system malfunctions such as leaks, pressure loss, or locking
  
• Electrical faults including sensor errors, wiring problems, or control panel failures
  
• Mechanical wear on boom components, joints, and pins causing operational difficulties
  
• Engine performance problems such as starting issues, overheating, or power loss
  
• Safety system alerts and faults triggering equipment shutdowns
  

Systematic Troubleshooting Approach

1. Visual and Physical Inspection
   • Check for fluid leaks, damaged hoses, worn or loose pins, and damaged wiring
     
   • Verify hydraulic fluid levels and engine oil conditions
     
   • Inspect safety devices and warning lights for error indications
     
2. Hydraulic System Checks
   • Measure hydraulic pressure at test points to identify pump or valve faults
     
   • Operate cylinders and actuators to observe for locking or sluggish response
     
   • Examine hydraulic filters for clogging or contamination
     
3. Electrical Diagnosis
   • Use diagnostic tools to read fault codes from control modules
     
   • Test wiring harnesses for continuity and proper connections
     
   • Inspect and test sensors for correct operation
     
4. Mechanical Component Evaluation
   • Check boom pins, bearings, and bushings for excessive play or wear
     
   • Lubricate moving parts as per maintenance schedules
     
   • Replace worn components to prevent failure during operation
     
5. Engine and Fuel System Maintenance
   • Perform standard engine tune-ups including spark plug, fuel filter, and air filter replacements
     
   • Test fuel delivery and injection systems for blockages or leaks
     
   • Monitor engine temperature and oil pressure gauges during operation
     

Terminology Explained

• Hydraulic Lock: Condition where fluid pressure prevents cylinder movement
  
• Control Module: Electronic unit managing equipment functions and diagnostics
  
• Diagnostic Codes: Numeric or alphanumeric fault indicators retrieved from control systems
  
• Boom Pins: Pivot points that connect sections of the boom and allow movement
  
• Actuators: Devices converting hydraulic pressure into mechanical movement
  

Preventive Maintenance Recommendations

• Follow manufacturer-specified maintenance intervals for fluids, filters, and lubrication
  
• Regularly calibrate sensors and test safety systems to ensure reliability
  
• Train operators in smooth control usage to reduce mechanical stress
  
• Maintain detailed service records to track component wear and repairs
  

Case Story
A construction firm operating several JLG aerial lifts faced frequent hydraulic lock issues. After a thorough hydraulic system flush and replacement of worn spool valves, combined with operator training on controlled lever movements, the incidents dropped significantly. This demonstrates the importance of combined mechanical and operational measures.
Summary of Key Troubleshooting Points

• Inspect hydraulic and electrical systems systematically
  
• Use diagnostic tools for accurate fault identification
  
• Replace worn mechanical parts proactively
  
• Maintain engine and fuel systems regularly
  
• Train operators on proper equipment handling
  

Conclusion
Proper troubleshooting and preventive maintenance are essential to keep JLG equipment operating safely and efficiently. Understanding the integration of hydraulic, electrical, mechanical, and engine systems aids in quick fault diagnosis and resolution. Combined with operator training and routine care, these measures extend equipment lifespan and reduce downtime.