Troubleshooting Auxiliary Hydraulics Stuck On

[MikePhua]

Auxiliary hydraulics are a crucial feature on many heavy equipment machines, such as skid steers, excavators, and compact track loaders. They allow operators to power various attachments like augers, mulchers, and grapples, providing greater flexibility and functionality. However, one common issue that can arise is the auxiliary hydraulics "sticking on," where the hydraulic function remains engaged, even when the control lever is in the neutral position. This problem can be both frustrating and potentially damaging to the machine if not addressed quickly.
In this article, we’ll explore the possible causes of auxiliary hydraulics getting stuck on, how to diagnose the issue, and the steps you can take to fix it.
Understanding the Auxiliary Hydraulic System
Auxiliary hydraulics are designed to provide additional hydraulic flow to attachments that require power beyond the machine's standard functions. The system typically consists of a hydraulic pump, valves, hoses, and quick-connect fittings to link the machine to the attachment. When the operator activates the control lever, it directs hydraulic fluid to the appropriate attachment, powering it for various tasks.
In a properly functioning system, once the operator releases the control lever, the hydraulic function should stop. However, issues like hydraulic leakage, valve failure, or electrical malfunctions can cause the auxiliary hydraulics to remain engaged.
Common Causes of Auxiliary Hydraulics Stuck On
Several issues can cause the auxiliary hydraulics to get stuck in the "on" position. Below are some of the most common causes:

1. Faulty Control Valve
   

The control valve is the main component that regulates the flow of hydraulic fluid to the attachment. When the control lever is moved, it opens or closes the valve to allow hydraulic fluid to pass through. Over time, the valve can wear out, become dirty, or suffer from internal damage, leading to failure in properly shutting off the hydraulic flow.

• Symptoms:
  • The auxiliary hydraulics remain engaged even when the control lever is in the neutral position.
    
  • The attachment continues to operate after releasing the control lever.
    
• Cause:
  • The control valve may be stuck in the open position due to dirt or debris.
    
  • Internal seals or components within the valve may be worn, causing fluid to continue flowing through the valve.
    
• Solution:
  • Clean the control valve and check for any obstructions or debris that could be preventing it from closing properly.
    
  • If cleaning doesn’t resolve the issue, the valve may need to be replaced. Inspect the valve for signs of wear or internal damage and replace it as necessary.
    

1. Hydraulic Leak or Pressure Issue
   

Hydraulic systems rely on precise pressure control to operate efficiently. If there is a leak in the hydraulic lines, fittings, or seals, it can cause a loss of pressure, leading to erratic behavior in the hydraulic system. In some cases, low pressure or a leak can cause the hydraulics to remain stuck on.

• Symptoms:
  • The auxiliary hydraulics might operate continuously at a reduced speed or power.
    
  • There may be visible signs of hydraulic fluid leaking from hoses, fittings, or the control valve area.
    
• Cause:
  • Leaks in hydraulic lines or connections can reduce the system's ability to maintain pressure, leading to improper operation of the hydraulics.
    
  • A damaged hydraulic pump could also result in irregular fluid pressure, causing the system to malfunction.
    
• Solution:
  • Inspect all hydraulic lines, hoses, and connections for visible signs of leaks. Tighten loose connections or replace damaged hoses.
    
  • Check the hydraulic fluid level and replenish if necessary.
    
  • If there are signs of internal damage in the pump or valves, consult the machine’s manual and replace the affected components.
    

1. Electrical or Solenoid Malfunction
   

Many modern machines use electrical solenoids to control hydraulic valves. These solenoids receive signals from the operator’s control lever, which in turn operates the valve to engage or disengage the hydraulic system. A malfunction in the electrical system, such as a faulty solenoid, a short in the wiring, or a control issue, can lead to the auxiliary hydraulics being stuck on.

• Symptoms:
  • The auxiliary hydraulics remain on or constantly activate without operator input.
    
  • The control lever appears unresponsive or intermittently fails to disengage the hydraulics.
    
• Cause:
  • A malfunctioning solenoid can keep the valve open, allowing hydraulic fluid to flow continuously.
    
  • Wiring issues or electrical shorts may cause the solenoid to malfunction, sending incorrect signals to the hydraulic system.
    
• Solution:
  • Inspect the solenoid for any signs of damage or wear. If the solenoid is faulty, replace it with a new one.
    
  • Check all wiring and connections leading to the solenoid for signs of corrosion, fraying, or disconnection. Repair or replace damaged wires.
    
  • Test the electrical circuit to ensure that the solenoid is receiving the correct signal from the control lever.
    

1. Sticking or Damaged Hydraulic Couplers
   

The quick-connect couplers used to attach hydraulic lines to attachments are essential for safely connecting and disconnecting auxiliary hydraulic systems. If the couplers become stuck, damaged, or corroded, they may cause the hydraulic system to malfunction, leading to the hydraulics staying engaged.

• Symptoms:
  • Difficulty in disconnecting the hydraulic lines from the attachment.
    
  • Hydraulic fluid leakage from the couplers.
    
• Cause:
  • The couplers may have worn seals or internal components that prevent proper disconnection, leading to the hydraulic fluid continuing to flow to the attachment.
    
• Solution:
  • Inspect the hydraulic couplers for signs of wear or damage. Clean the couplers and check for any debris that could be preventing them from disengaging properly.
    
  • Replace damaged or worn couplers to restore proper functionality to the auxiliary hydraulic system.
    

Steps to Diagnose and Fix the Problem

1. Check the Control Valve and Lever:
   Start by testing the control valve. Ensure that the control lever is functioning correctly and is in the neutral position when you attempt to disengage the hydraulics. If the valve feels sticky or unresponsive, it may need cleaning or replacing.
   
2. Inspect for Leaks:
   Check the hydraulic system for any visible leaks around the control valve, hydraulic lines, or couplers. Leaks can cause low pressure, which may result in the hydraulics staying on. Tighten any loose connections and replace any damaged hoses.
   
3. Test the Solenoid:
   If your machine uses an electrically-controlled hydraulic system, test the solenoid to make sure it is working as expected. A malfunctioning solenoid can keep the hydraulic valve engaged even if the operator does not request it.
   
4. Examine the Hydraulic Fluid:
   Low hydraulic fluid levels or contaminated fluid can lead to issues with hydraulic performance. Check the fluid level and condition, and top off or replace it if necessary.
   
5. Consult the Operator’s Manual:
   If the issue persists, consult the operator’s manual for specific troubleshooting procedures for your machine’s hydraulic system. The manual may offer additional guidance or insights into solving the problem.
   

Preventing Future Auxiliary Hydraulic Issues
To avoid future problems with auxiliary hydraulics getting stuck on, it’s essential to regularly maintain the system. Here are some tips to keep the system in top working condition:

1. Perform Regular Hydraulic System Inspections:
   Periodically check for leaks, worn hoses, or damaged fittings. Look for signs of fluid contamination and replace the hydraulic fluid according to the manufacturer’s recommendations.
   
2. Clean and Lubricate the Control Valve:
   Regularly clean the control valve and lubricate its moving parts to prevent it from becoming sticky or clogged.
   
3. Check Electrical Components:
   Ensure the solenoid and wiring are free from corrosion, and replace any damaged electrical components promptly.
   
4. Test the Hydraulics Before Heavy Use:
   Always test the auxiliary hydraulics before starting heavy work to ensure the system is functioning properly.
   

Conclusion: Keep Your Auxiliary Hydraulics Running Smoothly
Auxiliary hydraulic systems are vital for getting the most out of your heavy equipment, but they can encounter issues like getting stuck on if not properly maintained. By understanding the common causes of these problems, diagnosing them accurately, and addressing them promptly, operators can keep their machines running efficiently and avoid costly repairs. Regular maintenance and inspection are key to ensuring your auxiliary hydraulic system stays in optimal working condition. With the right care, you can maximize your machine’s versatility and productivity.