Hydraulic Tank Leaks on the John Deere 135C RTS: Causes, Troubleshooting, and Solutions

[MikePhua]

Introduction
The John Deere 135C RTS (Rubber Track Skid Steer) is a heavy-duty machine used for various tasks such as digging, grading, and lifting. Hydraulic systems play a crucial role in the functionality of these machines, driving everything from the arm movement to the tracks. One common issue that can disrupt the performance of such machines is hydraulic tank leaks. These leaks can severely impair the operation of the hydraulic system and lead to fluid loss, affecting both the performance and safety of the machine.
In this article, we will explore the causes of hydraulic tank leaks in the John Deere 135C, how to troubleshoot and diagnose these leaks, and the solutions to ensure the machine is operating efficiently. Additionally, we will discuss the importance of proper maintenance and offer tips on preventing such issues in the future.
Understanding the Hydraulic System of the John Deere 135C
The hydraulic system in any heavy machinery, including the John Deere 135C, consists of various components, including hydraulic pumps, valves, cylinders, hoses, and hydraulic fluid reservoirs. These components work together to power the machine's movements and various attachments. In the case of the 135C, the hydraulic tank serves as the storage reservoir for hydraulic fluid, which is then pumped throughout the system.
When a leak occurs in the hydraulic tank, it can result in the loss of hydraulic fluid, leading to reduced performance, overheating, and eventually, system failure. A leak in the hydraulic tank is often a sign of underlying issues such as pressure buildup, faulty seals, or damage to the tank itself.
Common Causes of Hydraulic Tank Leaks

1. Damaged Seals or Gaskets: Over time, the seals and gaskets that protect the hydraulic tank from leakage can wear out. Extreme temperatures, pressure changes, and general wear and tear can cause the seals to crack or become brittle, resulting in leaks.
   
2. Corrosion or Rust: Hydraulic tanks are typically made of steel or aluminum, which can corrode if exposed to moisture or harsh environmental conditions. Rust and corrosion can weaken the tank, causing it to develop leaks. This is particularly common in machines that are used in humid or coastal areas where water exposure is frequent.
   
3. Overpressure in the Hydraulic System: The hydraulic system in a machine operates under high pressure, and if there is a blockage or malfunction in the system, it can lead to excessive pressure in the tank. This pressure buildup can cause the tank to rupture or leak, especially if the tank or its components are already weakened from wear.
   
4. Loose or Damaged Fittings: Hydraulic fittings connect various parts of the hydraulic system, including the tank. If these fittings become loose or damaged, they can cause leaks. Vibration, impact, or improper installation can lead to fittings loosening over time.
   
5. Impact or Physical Damage: If the machine is involved in a collision or harsh operation, the hydraulic tank may be subjected to impact forces that can cause dents, cracks, or punctures, leading to fluid leakage. This is especially common in machines used in rugged or construction environments.
   

Signs of a Hydraulic Tank Leak
Recognizing a hydraulic tank leak early can save you from costly repairs and downtime. Here are some common signs that indicate a hydraulic tank leak:

• Visible Puddles or Pools of Fluid: One of the most obvious signs of a hydraulic tank leak is the presence of hydraulic fluid on the ground or under the machine. These puddles or pools often appear directly below the hydraulic tank or at points where the hydraulic system is connected.
  
• Low Hydraulic Fluid Levels: If you frequently have to top up the hydraulic fluid, it’s a clear indication that there is a leak somewhere in the system. A drop in fluid levels can also be caused by a malfunctioning pump or valve, but it’s often a sign of a tank leak.
  
• Erratic or Slow Movements: A hydraulic tank leak can lead to a loss of fluid, which means there is less hydraulic fluid available to power the machine’s functions. This can cause the machine to move erratically or slowly, and you may notice that the hydraulic cylinders or tracks are not functioning as smoothly as they should.
  
• Unusual Noises: If the hydraulic pump is struggling to draw fluid because of a low fluid level caused by a tank leak, it may produce whining or grinding noises. These sounds can indicate that the pump is working harder than usual due to insufficient hydraulic fluid.
  

Troubleshooting Hydraulic Tank Leaks

1. Inspect for Leaks: Start by thoroughly inspecting the hydraulic tank and all associated components for visible signs of leakage. Check the tank’s surface, connections, and seals for any obvious signs of fluid escaping. Look for puddles or streaks of fluid around the tank area.
   
2. Check the Fluid Level: If the fluid level is low, this is a sign that there is a leak somewhere in the system. Before proceeding, ensure that the hydraulic fluid level is topped off, as running the machine with low fluid can cause additional damage.
   
3. Pressure Test the System: If you suspect that the leak is due to overpressure in the system, perform a pressure test to identify any weak points in the system. Anomalies in pressure readings can indicate areas of concern such as damaged valves, pumps, or hoses.
   
4. Examine Seals and Fittings: Carefully check the seals, gaskets, and fittings for any signs of wear, cracks, or damage. You may need to replace seals or tighten fittings to stop the leak.
   
5. Look for Corrosion: If rust or corrosion is found on the tank, it may need to be replaced or repaired. Corrosion can weaken the tank, and sealing the leaks temporarily may not provide a long-term solution.
   

Solutions to Hydraulic Tank Leaks

1. Replace Damaged Seals and Gaskets: If seals or gaskets are found to be the cause of the leak, replacing them is the most straightforward solution. Ensure that you use OEM (Original Equipment Manufacturer) parts to guarantee proper sealing.
   
2. Repair or Replace the Tank: If corrosion or impact damage has caused the tank to crack or leak, you may need to repair or replace the tank. In some cases, minor damage can be repaired using welding or other methods, but severe corrosion may necessitate a full tank replacement.
   
3. Tighten or Replace Fittings: Tighten any loose fittings, or replace damaged ones. Ensure that all hydraulic fittings are properly torqued to the manufacturer’s specifications.
   
4. Flushing the System: Once the leak has been fixed, you may need to flush the hydraulic system to remove any contaminants that may have entered during the leak. This will help ensure that the system operates efficiently and prevent further damage.
   

Preventive Maintenance to Avoid Hydraulic Tank Leaks

1. Regular Inspections: Perform regular inspections of the hydraulic system, including the tank, hoses, fittings, and seals. Catching issues early can prevent major leaks from developing.
   
2. Check Fluid Levels Frequently: Monitoring the fluid level will allow you to notice any drop in the hydraulic fluid, which can be a sign of an ongoing leak.
   
3. Use Quality Hydraulic Fluid: Always use high-quality hydraulic fluid and follow the manufacturer’s recommendations. Poor quality or incorrect fluid can accelerate wear on seals and hoses, leading to leaks.
   
4. Address Rust and Corrosion: Regularly check the tank for signs of corrosion, particularly in areas that are exposed to harsh weather or environments. Proper cleaning and protective coatings can help prevent rust buildup.
   
5. Operate within Limits: Avoid overloading the machine and operating it under conditions that may cause undue stress on the hydraulic system. Always follow the operating guidelines in the owner’s manual to prevent issues such as overpressure.
   

Conclusion
Hydraulic tank leaks on the John Deere 135C can result in significant downtime and repair costs if not addressed promptly. By understanding the common causes of leaks, recognizing the signs early, and performing regular maintenance, you can ensure that your machine remains in top working condition. Whether it’s replacing damaged seals, addressing overpressure issues, or repairing a corroded tank, taking the proper steps to diagnose and fix hydraulic tank leaks will prolong the life of your equipment and minimize costly repairs.