Restoring and Modifying the Daewoo DH130-2 Excavator

[MikePhua]

Background of the DH130-2
The Daewoo DH130-2 excavator, introduced in the early 1990s, was part of Daewoo’s push to expand its presence in the global construction equipment market. Daewoo Heavy Industries, founded in South Korea in 1967, had already established itself in shipbuilding and automotive manufacturing before entering the heavy equipment sector. The DH130-2 was designed as a mid-size hydraulic excavator, offering a balance of power, maneuverability, and affordability. With an operating weight of approximately 13 metric tons and a bucket breakout force exceeding 9,000 kgf, it became a popular choice for contractors working in road building, utility trenching, and site preparation.
Though production of the DH130-2 ceased in the late 1990s, thousands of units were sold across Asia, Europe, and North America. After Daewoo’s acquisition by Doosan in 2005, parts support continued under the Doosan brand, though some components—especially drivetrain and control systems—became harder to source.
Switching Control Patterns Without a Diverter Valve
One of the challenges faced by operators of older excavators like the DH130-2 is adapting the control pattern. Modern machines often include a valve diverter or electronic switch to toggle between ISO and SAE control layouts. The DH130-2 lacks this feature, requiring manual reconfiguration.
To switch control patterns:

• Identify the pilot control hoses beneath the operator’s cab.
  
• Carefully label each hose according to its function (boom, stick, bucket, swing).
  
• Swap the hoses to match the desired pattern, ensuring no kinks or tension.
  
• Test the controls at low engine speed to confirm proper response.
  

This method is effective but requires precision. A misrouted hose can lead to erratic movement or hydraulic strain. Mechanics often recommend installing quick-connect fittings to simplify future changes.
Final Drive Repairs and Gear Replacement
The final drive on the DH130-2 is a planetary gear system, responsible for converting hydraulic power into track movement. Common wear points include the sun gear, planet gears, and carrier assembly. When disassembling the final drive:

• Remove the outer cover and inspect for metal shavings or oil contamination.
  
• Replace worn gears with OEM or compatible aftermarket kits. Spur gear kits are still available through select Doosan dealers.
  
• Check the bearing preload and seal integrity before reassembly.
  

In one case, a field mechanic in Manitoba successfully rebuilt a DH130-2 final drive using a Hy-Dash replication kit, confirming compatibility with Nabtesco-manufactured components. Nabtesco, a Japanese firm specializing in motion control systems, supplied transmissions for several Daewoo models during the 1990s.
Transmission and Hydraulic System Notes
The DH130-2 uses an open-center hydraulic system with a variable displacement pump. Its transmission, based on Hy-Dash architecture, is robust but sensitive to contamination. Operators should:

• Replace hydraulic filters every 500 hours.
  
• Use ISO 46 hydraulic oil in temperate climates, switching to ISO 68 in warmer regions.
  
• Monitor pilot pressure and main relief settings to prevent sluggish operation.
  

A technician in Lincoln, UK, noted that transmission schematics for the DH130-2 closely resemble early Komatsu designs, suggesting cross-compatibility in some service procedures.
Parts Availability and Dealer Support
While Daewoo-branded parts are increasingly rare, Doosan dealers can often source legacy components. Spur gear kits, seals, and pilot control hoses remain available in select regions. For hard-to-find items, salvage yards and online marketplaces offer used assemblies, though quality varies.
Operators are advised to:

• Record serial numbers and transmission codes before ordering parts.
  
• Cross-reference with Hy-Dash or Nabtesco catalogs when possible.
  
• Consider fabricating non-critical components like covers or brackets locally.
  

Operator Stories and Field Experience
One owner in Maine shared his experience restoring a 1995 DH130-2. After swapping control hoses and rebuilding the final drive, the machine returned to full operation. He emphasized the importance of documenting hose routing and using labeled diagrams during reassembly. Another operator in Alberta recalled using a DH130-2 for pipeline trenching in frozen soil, praising its torque but noting the need for frequent seal replacements.
Conclusion and Recommendations
The Daewoo DH130-2 remains a capable excavator for those willing to invest in maintenance and customization. Its mechanical simplicity and durable frame make it ideal for owner-operators and small contractors. To ensure longevity:

• Maintain clean hydraulic fluid and monitor gear wear.
  
• Retrofit control systems for ergonomic operation.
  
• Source parts proactively and build relationships with legacy dealers.
  

Though no longer in production, the DH130-2 continues to serve as a testament to Daewoo’s engineering and the resilience of 1990s-era heavy equipment. With careful upkeep, it can remain a valuable asset for years to come.