First Impressions of the IHI 35N Mini Excavator and Ownership Insights

[MikePhua]

The IHI 35N and Its Place in Compact Equipment History
The IHI 35N is a 3.5-ton class mini excavator produced by Ishikawajima-Harima Heavy Industries, a Japanese company with a long legacy in aerospace, shipbuilding, and industrial machinery. IHI entered the compact equipment market in the 1980s, aiming to deliver durable, operator-friendly machines for tight job sites. The 35N model, introduced in the early 2000s, was designed for residential excavation, utility trenching, and light demolition.
With an operating weight of approximately 7,800 lbs and a digging depth of over 10 feet, the 35N offered a strong balance of reach and stability. It was powered by a Yanmar diesel engine, known for fuel efficiency and low emissions. The machine featured an enclosed cab, auxiliary hydraulics, and a factory-installed hydraulic thumb—making it versatile for material handling and debris sorting.
Terminology:
- Hydraulic Thumb: A pivoting clamp mounted on the boom, used to grasp and manipulate objects. - Auxiliary Hydraulics: Additional hydraulic lines that allow the use of attachments like augers, breakers, or thumbs.
Buying a Used Mini Excavator and Evaluating Condition
Purchasing a used mini excavator like the IHI 35N requires careful inspection. In one case, a 2004 unit with 1,400 hours was acquired in California. The machine appeared well-maintained, with tight pins, clean hydraulics, and minimal cosmetic damage. The enclosed cab was intact, and the thumb operated smoothly.
Key inspection points included:

• Checking for hydraulic leaks around the boom and arm cylinders
  
• Verifying track tension and sprocket wear
  
• Testing swing function and travel motors
  
• Reviewing service records and previous ownership
  

While the machine passed most checks, the buyer expressed concern about parts availability, as IHI dealerships were sparse in the region. This is a common issue with niche brands, especially those that have exited certain markets or merged with other manufacturers.
Terminology:
- Track Tension: The tightness of the rubber or steel tracks, affecting traction and wear. - Swing Function: The ability of the upper structure to rotate independently of the undercarriage.
Parts Availability and Dealer Network Challenges
IHI’s compact equipment division was eventually absorbed into Kato Works, another Japanese manufacturer. As a result, parts support for older IHI models became fragmented. In the U.S., parts distribution was handled by a few regional suppliers, with one major hub located in Kentucky.
Owners of IHI machines often rely on:

• Cross-referencing part numbers with Kato equivalents
  
• Sourcing aftermarket components from hydraulic shops
  
• Fabricating custom bushings, hoses, or brackets when OEM parts are unavailable
  
• Joining equipment forums and user groups for shared resources
  

In 2019, a contractor in Oregon retrofitted an IHI 35N with a custom quick coupler sourced from a Bobcat dealer, adapting it with spacer plates and modified pins. The result was a fully functional attachment system that allowed the use of modern buckets and tools.
Terminology:
- Quick Coupler: A device that allows fast attachment changes without manual pin removal. - Spacer Plate: A fabricated shim used to adjust fitment between components.
Performance and Operator Experience
Operators generally praise the IHI 35N for its smooth controls and responsive hydraulics. The boom and arm offer good breakout force for a machine of its size, and the thumb adds significant utility in cleanup and material handling. The enclosed cab provides comfort in dusty or rainy conditions, though visibility can be slightly limited compared to canopy models.
Performance highlights:

• Smooth joystick control with proportional response
  
• Stable digging platform even on uneven terrain
  
• Efficient fuel consumption under moderate load
  
• Quiet engine operation with minimal vibration
  

One operator noted that the machine excelled in trenching for irrigation lines, allowing precise cuts without over-digging. Another used the 35N to clear brush and small stumps, leveraging the thumb to stack debris for burning.
Terminology:
- Breakout Force: The maximum force exerted by the bucket tip during digging. - Proportional Response: Hydraulic control that varies output based on joystick input pressure.
Maintenance Tips and Ownership Advice
Maintaining a mini excavator like the IHI 35N involves regular checks and preventive care. Owners should focus on:

• Greasing all pivot points weekly, especially the thumb and bucket linkage
  
• Changing hydraulic filters every 500 hours
  
• Inspecting track rollers and idlers for wear
  
• Monitoring coolant and engine oil levels before each shift
  

For machines with limited dealer support, it’s wise to build a parts inventory of common wear items—filters, seals, hoses, and pins. Keeping a service log and photographing repairs can help with resale and troubleshooting.
In one case, a rural contractor installed a solar trickle charger to maintain battery health during winter storage. This simple upgrade prevented dead starts and extended battery life by two seasons.
Terminology:
- Idler: A wheel that guides and tensions the track without driving it. - Trickle Charger: A low-current battery charger that maintains charge over long periods.
Conclusion
Owning an IHI 35N mini excavator offers a rewarding experience for those willing to navigate parts sourcing and brand-specific quirks. Its compact size, hydraulic thumb, and enclosed cab make it a capable tool for small-scale excavation and material handling. While dealer support may be limited, resourceful owners can keep these machines running strong through adaptation and community knowledge. The IHI 35N may be a lesser-known name, but its performance and reliability earn it a respected place in the compact equipment world.