Troubleshooting S-85 Boom Retracting Issues

[MikePhua]

The S-85 boom lift is a versatile piece of aerial equipment, commonly used in construction, maintenance, and warehousing for reaching heights and performing tasks that require an elevated work platform. However, like all heavy machinery, the S-85 can sometimes face mechanical issues that affect its operation. One of the most commonly reported problems with the S-85 is a failure to retract the boom properly. This article will explore the potential causes of this issue, diagnostic steps to take, and practical solutions to ensure that your S-85 boom lift is functioning optimally.
Understanding the S-85 Boom Lift System
Before diving into troubleshooting, it’s important to understand the key components involved in the boom lift’s operation. The S-85 is an articulating boom lift, which means it uses hydraulic arms and joints to extend and retract. The boom lift’s hydraulics are controlled by the hydraulic system, which includes a variety of components like cylinders, pumps, hoses, valves, and fluid.

• Hydraulic Cylinders: These are the primary components that extend and retract the boom. They work by pushing hydraulic fluid under pressure into a cylinder to move the boom.
  
• Hydraulic Fluid: Essential for transferring power through the hydraulic system. The right level and quality of fluid are crucial for smooth operation.
  
• Control Valves: These valves direct the flow of hydraulic fluid to different parts of the system, controlling the movement of the boom.
  
• Pump: The hydraulic pump supplies the hydraulic fluid under pressure to the system, providing the necessary force for boom movement.
  

Any issue with one of these components can lead to problems, such as the inability to retract the boom.
Common Causes for the Boom Not Retracting

1. Hydraulic Fluid Issues
   

One of the most common reasons why the boom may not retract is an issue with the hydraulic fluid. The system relies on properly pressurized fluid to function correctly, and if the fluid is too low or contaminated, it can cause erratic or incomplete operation.

• Low Hydraulic Fluid: If the fluid level is too low, there won’t be enough pressure to retract the boom fully.
  
• Contaminated Fluid: Dirt, debris, or moisture in the hydraulic fluid can damage seals and internal components, causing the boom to become stuck or malfunction.
  
• Air in the Hydraulic System: Air pockets in the hydraulic lines can lead to incomplete retraction. This can happen if the fluid has been recently changed or if there are leaks in the system.
  

Solution: Check the hydraulic fluid level and top it up as needed. Replace the fluid if it’s contaminated or appears dirty. If air in the system is suspected, perform a bleeding procedure to remove any trapped air.

1. Faulty Hydraulic Cylinders
   

The hydraulic cylinders are directly responsible for the extension and retraction of the boom. If these cylinders become damaged, corroded, or worn out, they may fail to function correctly, leading to difficulty retracting the boom.

• Damaged Seals: Over time, the seals in the hydraulic cylinders can wear out, allowing hydraulic fluid to leak, reducing the effectiveness of the boom’s retraction.
  
• Internal Cylinder Wear: Wear on the cylinder’s internal components can lead to a loss of pressure, making it difficult for the cylinder to push the boom back into its retracted position.
  

Solution: Inspect the hydraulic cylinders for visible damage, including leaks or signs of wear. If necessary, have the cylinders rebuilt or replaced to restore proper function.

1. Control Valve Malfunctions
   

The control valve is responsible for directing hydraulic fluid to the appropriate areas, such as the boom cylinders. If the control valve malfunctions, it may prevent the hydraulic fluid from reaching the correct parts of the system, leading to issues like failure to retract the boom.

• Sticking Valves: Over time, control valves can become sticky or clogged, causing them to fail to open or close fully.
  
• Faulty Solenoid Valves: These electrically controlled valves can fail due to electrical issues, preventing the hydraulic fluid from being directed properly.
  

Solution: Inspect the control valves for any signs of blockages or malfunction. Clean or replace faulty valves as necessary to restore proper fluid flow.

1. Pump Issues
   

The hydraulic pump is responsible for generating the pressure needed to operate the hydraulic system. If the pump is not producing enough pressure, it can affect the boom’s ability to retract.

• Worn or Damaged Pump: Over time, the pump’s components can wear down, reducing its ability to generate the necessary pressure.
  
• Pump Cavitation: If there’s an issue with the pump’s intake system, it may experience cavitation, where air bubbles form inside the pump, reducing its efficiency.
  

Solution: Test the hydraulic pump to ensure it is generating the correct pressure. If the pump is not functioning correctly, it may need to be repaired or replaced.

1. Electrical Issues
   

Electrical components can also play a role in the boom’s operation, especially if the S-85 is equipped with electric solenoids to control hydraulic valves. If there’s an electrical issue, the hydraulic system may not function properly, preventing the boom from retracting.

• Faulty Wiring: Wiring issues, such as loose or corroded connections, can prevent signals from reaching the solenoids, causing the boom to remain extended.
  
• Defective Solenoids: Solenoids that control the hydraulic valves can fail due to electrical faults, preventing the boom from moving.
  

Solution: Inspect the electrical wiring and solenoids for any signs of damage. Test the solenoids with a multimeter to check for proper function. Repair or replace any faulty components.
Preventative Maintenance for Smooth Boom Operation
To minimize the chances of encountering issues with the boom retraction, regular maintenance of the S-85 boom lift is crucial. Here are some key maintenance practices to keep in mind:

• Regular Fluid Checks: Always monitor the hydraulic fluid levels and ensure they are within the recommended range. Perform routine fluid changes and use the manufacturer-recommended fluid type.
  
• Inspect Hydraulic Components: Periodically check hydraulic hoses, cylinders, and fittings for leaks or damage. Replace any worn components promptly to avoid further damage.
  
• Clean the System: Regularly clean the hydraulic system, including filters and valves, to prevent debris buildup that could clog or damage the system.
  
• Check Electrical Connections: Inspect all electrical connections, wiring, and solenoids to ensure they are secure and free of corrosion.
  
• Test the Boom Movement: Conduct regular boom movement tests to ensure the lift operates smoothly. Pay attention to any hesitations or irregularities, which may indicate a problem early on.
  

Conclusion
If your S-85 boom lift isn’t retracting, it’s important to conduct a thorough diagnosis to pinpoint the issue. Common causes include low hydraulic fluid, cylinder malfunctions, control valve issues, pump failure, or electrical faults. By addressing these problems early and performing regular maintenance, you can ensure that your S-85 boom lift continues to perform at its best, reducing downtime and avoiding costly repairs. Regularly checking the hydraulic system, inspecting key components, and staying on top of maintenance will help you keep your equipment in optimal working condition.