Reviving a 1986 National 326A Crane for Welding and Machinery Transport

[MikePhua]

The National 326A and Its Industrial Legacy
The National 326A is a two-stage boom truck crane with a swing-stowed jib, manufactured in 1986 by National Crane Corporation, a company known for producing durable, truck-mounted lifting solutions for construction, utility, and industrial sectors. During the 1980s, National’s cranes were widely adopted across North America for their simplicity, mechanical reliability, and adaptability to various chassis platforms. The 326A was often mounted on International trucks, and its compact design made it ideal for urban lifting, small-scale rigging, and mobile welding operations.
With a lifting capacity in the 10–14 ton range depending on configuration, and a boom reach of approximately 60 feet with jib extension, the 326A remains a viable option for owner-operators who need a versatile rig for non-commercial use—such as transporting excavator buckets, machine shop equipment, or setting steel for fabrication projects.
Essential Maintenance Before Returning to Service
Before putting a dormant crane like the 326A back into service, especially after years of inactivity, a thorough inspection and maintenance plan is critical. The upper works—meaning the crane components above the turntable—require special attention.
Recommended steps include:

• Inspect and lubricate wire rope for fraying, corrosion, or kinking
  
• Grease boom wear pads and check for excessive wear or misalignment
  
• Examine hydraulic hoses for cracking, abrasion, or leaks
  
• Grease the turntable bearing and check for axial and radial play
  
• Inspect swing pinion gear for backlash or uneven wear
  
• Verify boom extension and retraction smoothness under load
  
• Check the jib stowage mechanism for locking integrity
  

A third-party crane inspection is highly recommended, even for non-commercial use. Certified inspectors can identify hidden issues such as internal hydraulic leaks, structural fatigue, or outdated safety components that may not be obvious during a visual walkaround.
Diagnosing Winch Spooling Issues
One of the most common problems in aging boom trucks is winch malfunction—particularly spooling down under light load. In this case, the winch spools up smoothly but struggles to spool down unless under significant load, and even then, it sounds strained.
This symptom points to a likely issue with the winch brake system. Most boom truck winches, including those from Braden (a common OEM for National cranes), use a spring-applied, hydraulically-released brake. When spooling down, hydraulic pressure releases the brake, allowing the drum to rotate. If the brake valve is sticking or the pressure seals are worn, the brake may not fully disengage, causing resistance or noise.
Key components to inspect:

• Brake valve and pressure seals
  
• Piston and clutch/friction discs inside the brake pack
  
• Hydraulic lines feeding the winch brake circuit
  
• Sprag clutch (used during winch-up) for proper engagement
  
• Drum bearings and shaft alignment
  

Rebuilding the winch is often the most effective solution. During disassembly, worn friction discs, hardened seals, or contaminated fluid may be discovered—each contributing to poor brake release. Braden’s technical manuals offer detailed troubleshooting guides and parts diagrams for most legacy winch models.
Truck Platform and Integration
The crane is mounted on an International truck powered by a DT466 diesel engine with a manual transmission. The DT466 is a legendary inline-six engine known for its longevity and ease of service. With proper maintenance, these engines routinely exceed 500,000 miles in vocational applications.
Before integrating the crane into regular use, the truck itself should be addressed:

• Replace brake components and verify air or hydraulic system integrity
  
• Inspect frame rails for rust, cracks, or fatigue near crane mounts
  
• Check PTO (power take-off) engagement and hydraulic pump output
  
• Update lighting and electrical systems for roadworthiness
  
• Address cosmetic issues that may affect visibility or safety
  

Even though the rig is intended for “not-for-hire” use, safety and reliability remain paramount—especially when lifting heavy loads or operating in public spaces.
Use Cases and Practical Benefits
A well-maintained National 326A mounted on a reliable truck can serve as a multi-role rig for:

• Transporting and setting machine shop equipment
  
• Moving excavator buckets, attachments, and small implements
  
• Supporting mobile welding and fabrication jobs
  
• Assisting in farm or industrial maintenance tasks
  
• Acting as a boom truck for steel erection or light rigging
  

Unlike commercial cranes, a private-use rig avoids DOT carrier regulations, but still benefits from professional-grade capability. For rural operators, fabricators, or small contractors, this setup offers independence and flexibility without the overhead of a full crane service business.
Conclusion
Restoring a 1986 National 326A crane for personal transport and welding use is a rewarding endeavor—blending mechanical restoration with practical utility. With careful attention to hydraulic systems, winch function, and structural integrity, the rig can be transformed into a dependable tool for lifting, hauling, and fabrication. In an era of increasingly complex equipment, the simplicity and durability of legacy machines like the 326A continue to prove their worth, especially in the hands of skilled, resourceful owners.