Rebuilding the Power Steering Motor on the Deutz 130-06 Tractor

[MikePhua]

The Deutz 130-06 and Its Hydraulic Steering System
The Deutz 130-06 tractor, manufactured during the late 1970s and early 1980s, was part of Deutz-Fahr’s push toward high-horsepower agricultural machines with air-cooled diesel engines and robust mechanical drivetrains. With a rated output of approximately 130 horsepower and a reputation for reliability in field conditions, the 130-06 became a popular choice across Europe and North America. Its power steering system, hydraulically assisted and integrated with the front axle pivot, was designed to reduce operator fatigue during long hours of fieldwork.
Unlike modern tractors with electronically controlled steering valves, the 130-06 uses a hydraulic orbital motor mounted near the steering column. This motor receives pressurized fluid from the main hydraulic pump and directs flow to the steering cylinders based on wheel input. Over time, seals within the motor degrade, leading to leaks—particularly around the output shaft.
Terminology Annotation
- Orbital Motor: A hydraulic motor that converts fluid pressure into rotary motion, commonly used in steering systems for tractors and loaders.
- Output Shaft Seal: A rubber or polymer seal that prevents hydraulic fluid from leaking around the rotating shaft of the motor.
- End Cap: The rear housing of the motor, often secured with bolts or snap rings, which contains internal components such as bearings and seals.
- Hydraulic Fluid Migration: The unintended movement of fluid through worn seals or damaged passages, leading to pressure loss or external leakage.
Symptoms of Steering Motor Failure
Operators may notice the following signs when the power steering motor begins to fail:

• Hydraulic fluid leaking from the output shaft area
  
• Increased steering effort, especially at low RPMs
  
• Whining or groaning noises during steering input
  
• Fluid level in the reservoir dropping without visible external leaks
  
• Difficulty removing the end cap due to internal pressure or corrosion
  

These symptoms typically indicate worn shaft seals, hardened O-rings, or internal scoring of the motor housing. In older units, rust buildup around the end cap can make disassembly challenging.
A Story from the Hudson Valley
In upstate New York, a farmer operating a Deutz 130-06 noticed fluid dripping beneath the steering column after long runs. Steering became progressively harder, and the reservoir required frequent top-offs. After removing the motor, he struggled to detach the end cap. A retired mechanic suggested using a strap wrench and applying gentle heat to the housing to break the seal. Once opened, the internal seals were brittle and cracked. He rebuilt the unit using a seal kit sourced from a hydraulic supplier and restored full steering function.
Disassembly and Rebuild Procedure
To rebuild the power steering motor:

• Disconnect hydraulic lines and drain fluid from the system
  
• Remove the motor from the steering column or frame mount
  
• Clean exterior surfaces to prevent contamination during disassembly
  
• Use a strap wrench or soft-jaw vise to rotate and remove the end cap
  
• Extract the output shaft and inspect for scoring or wear
  
• Replace all seals, O-rings, and bearings using a compatible rebuild kit
  
• Reassemble with clean hydraulic fluid and torque bolts to spec
  
• Bleed the system by cycling the steering lock-to-lock several times
  

If the end cap is seized, apply penetrating oil and allow it to soak overnight. Avoid using chisels or hammers, which can damage the housing and compromise sealing surfaces.
Recommendations for Preventative Maintenance
To extend the life of the steering motor:

• Replace hydraulic fluid every 500 hours or annually
  
• Use fluid that meets ISO VG 46 or AW-46 specifications
  
• Inspect seals and hoses during seasonal service intervals
  
• Avoid overloading the front axle with excessive ballast
  
• Keep the steering system clean and free of dust or debris
  
• Monitor for early signs of leakage and address promptly
  

For tractors stored outdoors, consider installing a steering column boot or shield to reduce exposure to rain and UV degradation.
Conclusion
Rebuilding the power steering motor on a Deutz 130-06 tractor is a manageable task that restores critical functionality and prevents further hydraulic loss. With proper tools, seal kits, and attention to detail, operators can extend the life of their steering system and maintain the responsive handling that made the 130-06 a favorite among field professionals. As vintage tractors continue to serve in modern operations, preserving their hydraulic systems becomes both a technical challenge and a tribute to enduring engineering.