Troubleshooting Yanmar VIO 20 Track Not Turning

[MikePhua]

Introduction
The Yanmar VIO 20 is a compact and powerful mini-excavator designed for versatility in tight spaces. However, like all heavy machinery, it can encounter issues from time to time. One common issue reported by users is when one or both tracks of the Yanmar VIO 20 fail to turn properly. This article explores the possible causes and solutions for this problem, helping operators get their equipment back in action.
Possible Causes for Tracks Not Turning
Several factors can cause the tracks on a Yanmar VIO 20 to stop turning as expected. These include problems related to the hydraulic system, track tension, or mechanical failure of key components. Understanding these causes is essential for diagnosing the issue accurately.

1. Hydraulic System Issues
   The Yanmar VIO 20’s tracks are powered by hydraulic motors that receive pressure from the machine’s hydraulic pump. If there is an issue with the hydraulic system, such as a pump failure, low fluid levels, or air in the hydraulic lines, the tracks may not turn or may operate erratically.
   • Low Hydraulic Fluid: Check the hydraulic fluid level regularly. Low fluid levels can reduce the pressure in the hydraulic system, causing the tracks to stop turning.
     
   • Hydraulic Pump Failure: If the hydraulic pump is malfunctioning, it won’t supply enough pressure to the motors that drive the tracks.
     
   • Air in Hydraulic Lines: Air bubbles in the hydraulic lines can disrupt fluid flow, causing insufficient power to the motors.
     
2. Track Tension Issues
   If the tracks are either too loose or too tight, they may not turn properly. Excessive slack in the tracks can cause them to skip or get stuck, while overly tight tracks can cause excessive friction, preventing proper movement.
   • Adjust Track Tension: Ensure that the track tension is set correctly according to the manufacturer’s specifications. Adjusting the tension may resolve issues related to improper movement.
     
3. Drive Motor Problems
   Each track is powered by a hydraulic motor connected to the drive system. If one of these motors malfunctions or experiences a mechanical failure, it can prevent that track from turning.
   • Faulty Hydraulic Motor: A failed or damaged hydraulic motor will not receive enough pressure to move the track. In some cases, a motor might need to be replaced.
     
   • Blocked or Leaking Motor Lines: Clogged or leaking lines can affect the flow of hydraulic fluid to the motor, causing one track to fail.
     
4. Control Valve Malfunction
   The control valve is responsible for directing hydraulic fluid to the appropriate areas of the machine, including the tracks. If the valve malfunctions, it can cause one track to stop turning.
   • Check Control Valve: A malfunctioning control valve may not be directing the hydraulic fluid correctly. Inspecting and repairing the control valve can restore proper function to the tracks.
     
5. Mechanical Failures
   In addition to hydraulic and tension-related issues, mechanical failures can also prevent the tracks from turning. These failures might include damaged sprockets, drive gears, or the undercarriage.
   • Inspect Sprockets and Gears: Check the sprockets, drive gears, and other moving parts for wear or damage. If any of these components are broken or worn out, they may need to be replaced.
     

Steps to Diagnose the Issue

1. Check Hydraulic Fluid Levels
   Begin by checking the hydraulic fluid levels. If the levels are low, add the appropriate fluid and test the tracks again. If the issue persists, move on to the next step.
   
2. Inspect the Hydraulic System
   Check for any obvious signs of leakage in the hydraulic lines, pump, or motor. You can also inspect the filter for blockages that might restrict fluid flow.
   
3. Adjust the Track Tension
   Use the track tensioning mechanism to ensure that the tracks are correctly tensioned. This will help avoid issues related to slippage or excessive resistance.
   
4. Test the Hydraulic Motors
   If the tracks are still not turning, the issue may lie with the hydraulic motors. Test the hydraulic motors by listening for unusual sounds or checking for a lack of movement in the motor pistons. If you suspect a motor failure, consult a professional to have the motor inspected or replaced.
   
5. Examine the Control Valve
   If there are no issues with the hydraulic fluid or motors, the control valve might be malfunctioning. A qualified technician can check the valve for proper operation and repair it if necessary.
   

Conclusion
If the tracks on your Yanmar VIO 20 aren’t turning properly, the issue could be related to the hydraulic system, track tension, drive motors, or a control valve malfunction. By systematically checking these components and troubleshooting the problem, operators can identify the cause and take the necessary steps to repair it. Regular maintenance of the hydraulic system, track tension, and moving parts will help prevent these issues in the future and ensure that the mini-excavator operates smoothly and efficiently.