John Deere 855 Front Track Idler: Troubleshooting and Solutions

[MikePhua]

The John Deere 855 is a well-known compact utility tractor, widely used in agriculture, landscaping, and construction. Like many pieces of heavy machinery, the 855 is subjected to wear and tear, especially in the undercarriage components, which include critical parts like the front track idler. The track idler plays a vital role in maintaining proper tension and alignment of the tracks, ensuring smooth operation.
A front track idler failure or performance issues can significantly affect the operation of the 855, causing downtime, inefficiency, or even damage to other components. In this article, we will explore common problems associated with the John Deere 855 front track idler, discuss troubleshooting techniques, and offer practical solutions to keep the machine running smoothly.
Understanding the Role of the Track Idler
The track idler is a key component in tracked vehicles like the John Deere 855. Located at the front of the undercarriage, the track idler's primary role is to guide the track and maintain its tension. It ensures that the track stays aligned and properly taut, preventing slippage and uneven wear. The track idler also helps distribute the weight of the vehicle evenly across the tracks, improving traction and extending the lifespan of the track system.
When the front track idler is functioning correctly, the vehicle’s tracks remain tight and aligned, allowing for smooth movement and optimal performance. However, if the idler begins to fail, it can lead to a range of issues, from poor traction to more serious mechanical damage.
Common Symptoms of a Malfunctioning Track Idler
Several signs can indicate that the front track idler on your John Deere 855 is malfunctioning or in need of attention:

1. Uneven Track Wear: If the tracks show uneven wear patterns, especially on one side, this can suggest that the track idler is not maintaining proper tension or alignment.
   
2. Excessive Noise: A worn or damaged track idler can produce excessive noise, such as squealing or grinding sounds, which is often a sign of worn-out bearings or a lack of lubrication.
   
3. Track Slippage: If the track frequently slips off or becomes loose, it may be due to a failure in the track idler's ability to maintain proper tension.
   
4. Uneven Track Movement: When the track moves erratically, jerking or skipping, it might indicate that the track idler is no longer able to keep the track aligned, leading to a rough ride.
   
5. Visible Wear or Damage: Over time, the idler itself may show signs of wear, such as cracks, dents, or erosion of the metal parts. If you notice these signs, it's crucial to inspect the component and replace it if necessary.
   

Causes of Front Track Idler Problems
Several factors can contribute to problems with the front track idler on the John Deere 855. Understanding these causes can help in troubleshooting and preventing future issues.

1. Lack of Maintenance: Like all mechanical components, the track idler requires regular maintenance, including proper lubrication and cleaning. Failure to maintain the idler can lead to rust, wear, and eventual failure.
   
2. Overloading: Constantly overloading the tractor can put excess pressure on the track idler, causing it to wear out prematurely. It is essential to adhere to the recommended load limits for your specific machine.
   
3. Improper Track Tension: Incorrect track tension can stress the idler, causing uneven wear. The tension must be adjusted correctly to ensure the track idler functions as designed.
   
4. Harsh Operating Conditions: Operating the John Deere 855 in extreme conditions—such as muddy, rocky, or abrasive environments—can accelerate wear on the track idler. The track idler is susceptible to damage from debris or foreign objects that get caught in the tracks.
   
5. Manufacturing Defects: While rare, sometimes a manufacturing defect in the track idler may cause premature wear or failure. If you notice that the idler is failing much sooner than expected, a defect could be the issue.
   

Troubleshooting the John Deere 855 Front Track Idler
If you suspect an issue with the front track idler, it’s important to diagnose the problem before attempting any repairs. Here’s a step-by-step troubleshooting guide to help you identify the root cause:

1. Inspect the Track: Check for signs of uneven wear, track slippage, or other damage. Take note of any unusual sounds coming from the tracks or undercarriage.
   
2. Check Track Tension: Ensure that the track is properly tensioned. Overly tight or loose tracks can contribute to idler problems. Use a tension gauge or the manufacturer’s guidelines to make the necessary adjustments.
   
3. Examine the Idler: Visually inspect the front track idler for any visible signs of wear, cracks, or damage. Look for worn bearings or parts that are not functioning correctly.
   
4. Lubrication Check: Ensure the track idler is properly lubricated. Lack of lubrication can cause components to seize or wear prematurely.
   
5. Test the Idler’s Movement: With the machine off, manually rotate the track idler to feel for smooth movement. If it feels rough or sticks, it may need lubrication or replacement.
   
6. Test the Hydraulic System: If your John Deere 855 features a hydraulic tensioning system for the tracks, ensure that the system is functioning properly. A malfunctioning hydraulic system can prevent the track from staying properly tensioned, which will affect the idler’s performance.
   

Solutions and Repairs
Once you’ve diagnosed the issue with the front track idler, there are several repair options available depending on the severity of the problem:

1. Lubrication: If the issue is related to a lack of lubrication, a simple application of grease or oil can often restore functionality. Ensure that the idler bearings are well-greased and that the lubrication is applied to all moving parts.
   
2. Track Adjustment: If the track is too tight or too loose, adjusting the track tension can often resolve the issue. Follow the manufacturer’s instructions to make the appropriate adjustments to the track tensioner.
   
3. Replacing Worn Parts: If the idler is showing significant wear, such as cracks or damaged bearings, it may need to be replaced. In some cases, it might be possible to replace only the damaged parts (such as the bearings), but if the idler housing is cracked, a full replacement may be necessary.
   
4. Professional Help: If you’re unable to diagnose or repair the issue yourself, it may be worth consulting a professional mechanic with experience in John Deere equipment. They can assess the problem and provide a solution, whether it’s a repair or a full replacement of the track idler.
   

Preventative Measures for Track Idler Longevity
To avoid future problems with the John Deere 855 front track idler, regular maintenance and proper operation are essential. Here are some tips to extend the life of your track idler:

1. Regularly Inspect Tracks and Idlers: Perform routine checks of the tracks and idlers to catch any signs of wear early. Regular inspections help prevent small issues from becoming big problems.
   
2. Lubricate Regularly: Ensure that the track idler is regularly lubricated, especially in harsh environments. Proper lubrication prevents friction and wear on moving parts.
   
3. Adhere to Load Limits: Avoid overloading the tractor beyond its recommended capacity to prevent undue stress on the tracks and idler.
   
4. Proper Track Tension: Maintain the proper tension on the tracks at all times. Both too tight and too loose tracks can lead to problems with the track idler.
   
5. Use the Equipment in Appropriate Conditions: Operate the John Deere 855 in conditions suited to its design, avoiding overly rocky, muddy, or abrasive environments whenever possible.
   

Conclusion
The John Deere 855 front track idler is an essential component of the machine’s undercarriage system, ensuring that the tracks remain properly tensioned and aligned. Malfunctions in the track idler can lead to poor machine performance, increased wear, and costly repairs. By understanding the role of the track idler, recognizing common symptoms of failure, and following a proper maintenance routine, you can ensure that your John Deere 855 runs efficiently for years to come.
Whether it's performing regular inspections, lubricating components, or addressing issues early, keeping the track idler in top condition is crucial for maintaining the longevity and performance of your heavy equipment.