Lull 644 Highlander: Features, Performance, and Troubleshooting

[MikePhua]

The Lull 644 Highlander is a versatile telehandler designed for heavy lifting and material handling in rough terrain. Widely used in construction, agriculture, and industrial applications, the Lull 644 is known for its powerful performance and unique capabilities. In this article, we’ll review the key features, common issues, and maintenance tips for the Lull 644 Highlander.
Key Features of the Lull 644 Highlander

1. Powerful Engine and Performance
   The Lull 644 Highlander is equipped with a robust engine that delivers high lifting power and excellent performance. The machine is designed to handle heavy loads and perform in tough environments, such as construction sites with rough or uneven terrain.
   • Engine Specifications: Typically powered by a diesel engine, the Lull 644 Highlander provides reliable torque and power to lift and transport materials.
     
   • Lifting Capacity: The telehandler offers an impressive lifting capacity, capable of handling loads up to 6,000 lbs, making it suitable for a wide range of applications.
     
2. 4WD and Rough Terrain Capabilities
   One of the standout features of the Lull 644 Highlander is its ability to operate on rough and uneven ground. The 4WD system provides excellent traction, ensuring that the telehandler can move easily in challenging terrain.
   • Off-Road Capabilities: With large tires and a high ground clearance, the Lull 644 can easily maneuver over obstacles such as rocks, mud, and sand.
     
   • Stability: The machine is designed to offer good stability, even when carrying heavy loads over uneven surfaces.
     
3. Versatile Lifting and Reach
   The Lull 644 Highlander comes with a telescoping boom that allows for extended reach, providing greater flexibility for lifting and stacking materials at height.
   • Boom Reach: The telehandler’s boom can extend to a height of approximately 44 feet, making it useful for reaching high places or placing materials on top of structures.
     
   • Precision: The boom can be precisely controlled to place materials with high accuracy, which is ideal for delicate or specific placements.
     
4. Operator Comfort and Safety
   The Lull 644 Highlander is designed with the operator’s comfort and safety in mind. The cab is spacious, with good visibility and controls that are easy to use.
   • Comfort: The operator’s seat is adjustable, and the controls are designed to reduce fatigue during long hours of operation.
     
   • Safety Features: The telehandler comes with built-in safety features such as an overload sensing system and stabilizers to prevent tipping when lifting heavy loads.
     

Common Issues with the Lull 644 Highlander

1. Hydraulic System Problems
   The hydraulic system is critical for the smooth operation of the Lull 644 Highlander, but it can encounter issues such as leaks, pressure loss, or slow operation. These issues can impact the lifting and boom extension functions.
   Solution:
   • Regularly check hydraulic fluid levels and top up as needed.
     
   • Inspect the hydraulic hoses, pumps, and valves for signs of damage or leaks.
     
   • If the hydraulic system is slow or unresponsive, it may indicate a need for a fluid change or a deeper issue with the hydraulic pump.
     
2. Engine and Fuel System Issues
   If the Lull 644 Highlander experiences power loss, hard starting, or stalls during operation, the issue could be related to the engine or fuel system. Common problems include clogged fuel filters, dirty injectors, or low-quality fuel.
   Solution:
   • Regularly replace the fuel filter and clean the fuel system.
     
   • Use clean, high-quality diesel fuel and ensure that the fuel tank is free from contaminants.
     
   • If the engine is misfiring or not starting, check the battery and electrical system, including connections and voltage.
     
3. Transmission and Drive System Failures
   Some operators have reported issues with the transmission or drive system, including difficulty in shifting gears or loss of power to the wheels. These issues can result from worn components or a malfunctioning transmission system.
   Solution:
   • Regularly check the transmission fluid levels and condition.
     
   • If there is a noticeable loss of power or difficulty in shifting, inspect the transmission and gear linkage for wear.
     
   • Replace any worn or damaged parts, such as seals, filters, or clutches, to ensure smooth transmission operation.
     
4. Electrical System Malfunctions
   Electrical issues, such as malfunctioning lights, faulty sensors, or error codes on the display panel, can sometimes occur in the Lull 644 Highlander. These issues are often due to wiring problems, blown fuses, or faulty sensors.
   Solution:
   • Check all electrical connections for corrosion or loose wiring.
     
   • Inspect fuses and replace any that are blown.
     
   • Test sensors and replace them if necessary to restore proper functionality.
     

Maintenance Tips for the Lull 644 Highlander

1. Regular Inspections
   Conduct routine inspections of key components, such as the hydraulic system, engine, transmission, and electrical system. Early detection of potential issues can prevent costly repairs and downtime.
   
2. Change Filters and Fluids
   Regularly change the hydraulic, engine, and fuel filters as part of routine maintenance. Also, change the oil and fluid levels at intervals recommended by the manufacturer to ensure optimal performance.
   
3. Clean the Machine
   Keep the Lull 644 Highlander clean, especially around the hydraulic system and engine. This will prevent dirt and debris from entering sensitive components and causing wear or damage.
   
4. Inspect Tires and Suspension
   Regularly check the condition of the tires for wear and tear, and inspect the suspension system for any issues. Proper tire pressure is essential for maintaining stability and traction in rough terrain.
   

Conclusion
The Lull 644 Highlander is a powerful and reliable telehandler that excels in lifting and material handling, particularly in rough terrain. With its 4WD system, versatile boom, and operator-friendly features, it is a preferred choice for many industries. However, like any machine, it can experience issues over time, such as hydraulic problems, engine failures, or transmission malfunctions. By performing regular maintenance, troubleshooting common issues, and addressing problems promptly, operators can ensure the longevity and performance of the Lull 644 Highlander for years to come.