In this discussion, users explore the issue of excavator boom arms rising on their own during operation. Various possible causes and solutions are shared.
Main Causes:

• Hydraulic System Leakage
  The most common cause is leakage in the hydraulic cylinder’s check valve or seals, causing hydraulic oil to flow back and the boom arm to slowly rise without operator input.
  
• Hydraulic Circuit Design
  Some excavators are designed with hydraulic circuits that allow slow oil flow, which may naturally cause slight boom arm movement upward.
  
• Load Effects
  The boom arm’s weight and load distribution can create an unbalanced force on the hydraulic cylinder, pushing hydraulic oil and causing the boom to rise.
  
• Control Valve Malfunction
  Worn or stuck control valves on the joystick can lead to hydraulic oil leakage or poor control, resulting in the boom arm rising by itself.
  

• Inspect hydraulic cylinder seals and replace damaged check valves.
  
• Confirm control valves are functioning properly.
  
• Maintain clean and sufficient hydraulic oil levels.
  

In this discussion, users analyze the common “curved boom” design found on many mini excavators, exploring its functions, advantages, and the design rationale behind it.
Main Points:

• Better Digging Angle and Depth
  The curved boom allows the excavator’s arm to achieve greater digging depth and an improved working range without increasing the overall machine length. This is especially beneficial for working in tight or confined spaces.
  
• Improved Maneuverability and Flexibility
  This design enables the excavator to operate more flexibly, allowing it to maneuver around obstacles and reach better angles during close-quarter operations. It is suitable for landscaping, municipal work, and construction sites.
  
• Avoiding Structural Interference
  The curved shape prevents interference between the boom and the cabin or the machine body, improving spatial utilization during operation.
  
• Enhanced Structural Strength
  Some users mentioned that through thoughtful structural design, the curved boom balances strength and weight distribution, thereby enhancing the durability and stability of the entire machine.
  
• Historical and Brand Differences
  Different manufacturers use various boom designs—some straight, some curved—depending on design philosophy and user requirements. Japanese brands like Komatsu and Kubota commonly adopt the curved boom design.
  

This discussion centers on whether a small excavator, such as the John Deere 26G, can be loaded into a 12-foot long by 6-foot wide low-side dump trailer. Users exchanged views about size compatibility, loading techniques, and transport safety considerations.
Main Discussion Points:

• Size Comparison
  The length and width of the 26G excavator generally slightly exceed the internal dimensions of a 12x6 ft trailer. Some users believe directly loading it may be difficult, especially regarding width. Precise measurement of both the machine’s width and the trailer’s interior is essential.
  
• Disassembly and Folding
  Suggestions include partially disassembling or folding the excavator’s boom or arm to reduce dimensions and ease loading. Adjusting the arm and bucket to a transport position can also save space.
  
• Loading Techniques
  Careful use of ramps or loading boards is recommended, ensuring proper angle and stability to prevent the excavator from slipping or tipping. Loading should be performed by experienced operators.
  
• Legal and Safety Considerations
  Transport width limits, height restrictions, and weight regulations must be observed. Properly securing the excavator on the trailer is critical to avoid shifting or loosening during transit.
  
• Trailer Selection
  For frequent transport of the 26G or similar-sized excavators, some users suggest investing in a larger trailer (e.g., 14 ft long or wider low-side dump trailer) to ensure safer and easier transportation.
  

The Yanmar B3 is a compact mini excavator suitable for light civil engineering and landscaping tasks. Users in the discussion shared their experiences regarding its performance, maintenance, and operation.
Key Discussion Points:

• Performance:
  Users generally agree that the Yanmar B3 is small and highly maneuverable, ideal for working in tight spaces. Its power is moderate, sufficient for everyday light digging tasks.
  
• Maintenance and Issues:
  Some users reported that hydraulic oil seals wear out relatively quickly and require regular replacement. The electrical system is relatively simple and easy to repair. Routine maintenance is emphasized to prolong machine life.
  
• Spare Parts Availability:
  Genuine parts offer good quality but tend to be expensive. In some regions, parts supply is limited, so it is advised to stock necessary spares in advance to avoid project delays.
  
• Operation Tips:
  Operators should be familiar with the controls, avoid overloading, and maintain machine balance during digging. Choosing the appropriate bucket size can improve work efficiency.
  
• User Modifications:
  Some users shared tips on upgrading and customizing their machines, such as adding auxiliary attachments and adjusting the hydraulic system.
  

The Yanmar B32 mini excavator is widely used in landscaping, agriculture, and small-scale construction projects due to its compact size and flexible operation. Users generally express satisfaction with its power and hydraulic system performance. However, maintenance is emphasized, especially regarding hydraulic oil and seal components.
Parts availability is another important consideration before purchase. Having spare parts on hand can help avoid downtime during operations.
For new users, it is recommended to rent the machine first to become familiar with its performance before making a purchase decision. Operators should always pay attention to machine balance to prevent accidents.
Overall, the B32 is considered a cost-effective lightweight excavator suitable for a variety of light-duty applications.

The bucket pins for the Yanmar B50 excavator typically have a diameter of around 35 millimeters. However, the exact length can vary depending on the bucket model and the manufacturing year of the machine.
When replacing bucket pins, it is recommended to first measure the existing pin dimensions precisely to avoid installation issues caused by size mismatches.
To ensure durability and proper fit, it is best to use genuine OEM parts. If opting for generic replacement pins, one must confirm that the specifications match exactly and pay close attention to material quality to maintain operational safety and efficiency.

This article summarizes a forum thread where multiple users discussed common error codes encountered on Yanmar excavators and their troubleshooting methods. The focus was mainly on engine faults and hydraulic system warnings.
1. Common Error Codes and Their Meanings

• Error Code A: Engine sensor fault, which may involve the intake pressure sensor or temperature sensor abnormalities.
  
• Error Code B: Insufficient hydraulic system pressure, possibly caused by hydraulic pump failure or oil circuit blockage.
  
• Error Code C: Electronic Control Unit (ECU) communication failure, which might be due to loose cable connections or ECU malfunction.
  

• Check Sensors and Wiring
  Verify the sensors’ functionality and ensure all wiring connections are secure, without looseness or breaks.
  
• Hydraulic Oil Inspection
  Regularly check hydraulic oil levels and quality to prevent alarms caused by low oil or degraded oil condition.
  
• Read Error Codes with Diagnostic Tools
  Use professional diagnostic equipment to retrieve precise fault codes rather than guessing or disassembling blindly.
  
• Software Updates
  Some models may resolve electronic faults and false alarms by updating the ECU software.
  

• Users recommend contacting authorized dealers or professional repair technicians when facing complex electronic faults to avoid secondary damage caused by improper disassembly.
  
• Experienced mechanics shared repair workflows and precautions for various Yanmar excavator faults.
  
• Some users suggest purchasing official service manuals and diagnostic tools for quicker and more accurate troubleshooting.
  

This summary is based on an old forum thread where multiple users shared their experiences, pros and cons, and buying advice regarding the Yanmar SV40 excavator.
1. Model Overview
The Yanmar SV40 is a medium-sized crawler excavator suitable for small to medium civil construction, agriculture, and landscaping projects. It balances power and agility, typically offering around 4 tons of operational capacity, making it versatile for various applications.
2. User Experience and Feedback
Power Performance
Users generally agree that the SV40 delivers good power. The engine responds quickly and meets daily construction demands effectively.
Hydraulic System
The hydraulic system runs smoothly and operates responsively. Some users mentioned the need for regular maintenance of hydraulic hoses and seals to prevent oil leaks.
Mobility
The machine offers good maneuverability with precise steering, making it suitable for working in tight or complex environments.
Operator Comfort
The cab is moderately spacious, equipped with a comfortable seat and good visibility, making long hours of operation more manageable.
3. Common Issues

• Hydraulic Oil Leaks
  Some users reported minor hydraulic oil leaks. Regular inspection of hydraulic hoses and connectors is recommended.
  
• Spare Parts Availability
  Certain parts may have longer supply cycles in overseas markets. Buyers should verify parts availability before purchase.
  
• Maintenance Costs
  Overall maintenance costs are moderate, though some parts are slightly more expensive compared to similar brands.
  

• Purchase Channels
  Choose reputable dealers and confirm after-sales service support.
  
• Used Market
  Second-hand SV40 units are reasonably priced, suitable for users with limited budgets but in need of reliable equipment. When buying used, focus on inspecting the hydraulic system and engine condition.
  
• Application Scenarios
  Ideal for diverse work needs, including small to medium earthmoving, landscaping, and farm operations.
  

This summary is based on an old forum thread where multiple users shared their experiences, pros and cons, and buying advice regarding the Yanmar Vio27-3 excavator.
1. Model Overview
The Yanmar Vio27-3 is a popular compact tracked mini excavator suited for landscaping, agriculture, and light construction work. It features a small body and agile operation, capable of working efficiently in confined spaces.
2. User Experience and Evaluation
Power and Operation
Many users find the Vio27-3 has sufficient power for daily tasks. It is easy to operate, especially effective in complex terrain or tight working conditions. The machine is responsive, and steering is flexible.
Durability and Maintenance
Generally, users consider the machine durable. However, some components, such as parts of the hydraulic system, require regular inspection and replacement. Yanmar is noted for good parts supply and after-sales support, although some specific parts may have longer lead times.
Hydraulic System
The hydraulic system performs stably and supports various attachments. Users advise timely hydraulic oil changes to avoid system faults.
Mobility and Comfort
The cab is well-designed with a comfortable seat and ergonomically arranged controls, reducing operator fatigue during prolonged use.
3. Buying Recommendations
Used Market
Many recommend buying a used Vio27-3 due to its reasonable price and stable performance. However, it is important to carefully check the hydraulic system, engine condition, and track wear, and avoid machines with accident damage or severe wear.
Parts and After-Sales
Prospective buyers should understand the local availability of spare parts and quality of after-sales service to prevent maintenance difficulties later.
Suitable Applications
This model is suitable for small-scale construction, landscaping, orchards, and farms, but is not designed for heavy-duty or long-term large-scale projects.
4. Common Issues and Solutions

• Hydraulic Oil Leaks
  Regularly inspect hydraulic lines and promptly repair leaks to prevent larger damage.
  
• Engine Starting Problems
  Some users report difficulties starting the engine in cold regions; using season-appropriate fuel and maintenance can help.
  
• Track Maintenance
  Due to the machine’s light weight, tracks wear relatively easily, so regular adjustment and cleaning are important.
  

A user posted on an old forum seeking advice about buying a used Hitachi UH083LC excavator — a model from the late 1980s to early 1990s. Because of its age, he was unsure about maintenance costs, operational performance, and parts availability, so he asked experienced members for their opinions.
1. Main Concerns from the Original Poster

• The machine is inexpensive but has high working hours.
  
• Concerned whether old machines tend to leak oil or have loose structures.
  
• Worried about the difficulty of sourcing spare parts.
  
• Curious about how this model performs compared to other excavators in the same tonnage class.