Troubleshooting Hydraulic Problems on a Bobcat 863 Skid Steer

[MikePhua]

The Bobcat 863 is a versatile and widely used skid steer loader, valued for its ability to handle a wide range of tasks, from construction to landscaping. Like any piece of heavy equipment, it relies heavily on its hydraulic system to power various attachments and functions. Hydraulic systems, however, are prone to issues due to the complexity and pressure demands of the components involved. If your Bobcat 863 experiences hydraulic problems, it’s important to diagnose the issue quickly and accurately to prevent damage and maintain optimal performance. This article explores common hydraulic problems in the Bobcat 863, their causes, and practical troubleshooting steps to help you get back to work efficiently.
Understanding the Hydraulic System of the Bobcat 863
Before diving into troubleshooting, it’s essential to understand the role of the hydraulic system in the Bobcat 863. The hydraulic system powers many critical functions of the skid steer, including:

• Lift Arms and Bucket: The hydraulic system controls the lifting and lowering of the arms and bucket, providing the force necessary for loading and unloading.
  
• Drive Motors: The hydraulic drive motors are responsible for the movement of the machine, enabling forward and backward motion.
  
• Attachments: Many Bobcat attachments, such as augers, breakers, and grapples, rely on hydraulic power to operate.
  

The Bobcat 863 uses a closed-loop hydraulic system, meaning the fluid circulates continuously within a closed network of hoses, pumps, and valves to power the machine’s components. Any issues in this network can lead to a loss of performance or complete failure of critical systems.
Common Hydraulic Problems in the Bobcat 863
There are several common hydraulic issues that can affect the performance of the Bobcat 863. Below are the most frequently encountered problems and their potential causes:
1. Hydraulic System Overheating
Overheating is one of the most common hydraulic issues, particularly during extended operation or heavy workloads. If the hydraulic system runs too hot, it can lead to fluid breakdown, causing seals and hoses to deteriorate.

• Causes:
  • Low hydraulic fluid levels.
    
  • Contaminated or degraded hydraulic fluid.
    
  • Faulty hydraulic cooling system (radiator or fan).
    
  • Clogged hydraulic filters.
    
• Signs of Overheating:
  • The hydraulic fluid may start to foam.
    
  • Sluggish response from the lift arms and other hydraulically powered components.
    
  • The temperature gauge reading on the machine’s dashboard is high.
    

2. Loss of Hydraulic Power
Loss of hydraulic power is another common issue that can affect the Bobcat 863. This can manifest as reduced lifting capacity, difficulty moving the machine, or slow hydraulic function.

• Causes:
  • Air in the hydraulic lines.
    
  • Leaking hydraulic hoses or connections.
    
  • Worn-out hydraulic pump.
    
  • Low hydraulic fluid levels.
    
• Signs of Loss of Hydraulic Power:
  • The machine struggles to lift or move.
    
  • Slow response time when activating hydraulic functions.
    
  • Unusual noises from the hydraulic pump or valves.
    

3. Hydraulic Fluid Leaks
Leaks are a frequent issue in hydraulic systems, and they can be caused by damaged hoses, seals, or fittings. Even a small leak can result in a significant loss of hydraulic pressure, which will degrade performance.

• Causes:
  • Cracked or worn hydraulic hoses.
    
  • Faulty seals or o-rings.
    
  • Loose or damaged fittings and connectors.
    
• Signs of Hydraulic Fluid Leaks:
  • Puddles of hydraulic fluid under the machine.
    
  • A drop in hydraulic fluid levels.
    
  • Visible fluid around hose connections or fittings.
    

4. Erratic Hydraulic Function
Erratic or unpredictable hydraulic function can occur when the system experiences pressure surges or fluid contamination. This issue may cause the machine to behave unpredictably, such as jerky arm movements or sudden drops in hydraulic pressure.

• Causes:
  • Contaminated hydraulic fluid (dirt, debris, or water).
    
  • Faulty control valves.
    
  • Improper fluid levels or fluid type.
    
• Signs of Erratic Hydraulic Function:
  • Unpredictable movements or jerking of the lift arms.
    
  • Hydraulic components fail to respond consistently.
    
  • Intermittent loss of hydraulic pressure.
    

Troubleshooting Hydraulic Issues on the Bobcat 863
If your Bobcat 863 is experiencing hydraulic problems, there are several steps you can take to diagnose and resolve the issue. Below is a practical troubleshooting guide to help you pinpoint the problem and get your machine back in working order.
Step 1: Check Hydraulic Fluid Levels
The first thing to check when experiencing hydraulic issues is the fluid level. Low fluid levels are a common cause of loss of hydraulic power and overheating.

• How to Check:
  • Locate the hydraulic fluid reservoir and ensure that the fluid is at the proper level, as indicated on the dipstick.
    
  • If the fluid level is low, top it off with the recommended hydraulic fluid.
    
• If Fluid is Low:
  • Inspect for leaks, as fluid loss can be caused by cracks or damaged hoses.
    
  • Ensure that the fluid is the correct type and clean; contaminated fluid can cause further issues.
    

Step 2: Inspect for Hydraulic Fluid Leaks
Leaks are a common issue that can quickly deplete hydraulic fluid levels, leading to a loss of power and system failure.

• How to Inspect:
  • Visually inspect all hydraulic hoses, fittings, and connections for signs of leaks.
    
  • Look for any wet spots, puddles under the machine, or noticeable drops in fluid levels.
    
  • Tighten any loose connections and replace any damaged hoses or seals.
    
• If Leaks Are Found:
  • Replace the affected hoses or seals.
    
  • Ensure that all connections are properly tightened to prevent future leaks.
    

Step 3: Inspect Hydraulic Filters and Fluid Condition
Clogged or contaminated filters can cause overheating and reduced hydraulic performance. It’s important to check the condition of both the hydraulic fluid and the filters.

• How to Inspect:
  • Replace any clogged or dirty hydraulic filters.
    
  • If the hydraulic fluid is discolored or smells burnt, it should be replaced, as degraded fluid can cause damage to the pump and other components.
    
• If Fluid or Filters Are Contaminated:
  • Perform a complete fluid flush to remove contaminants.
    
  • Install new, high-quality hydraulic filters to prevent further contamination.
    

Step 4: Test the Hydraulic Pump
A faulty hydraulic pump can lead to a loss of hydraulic power, causing the machine to operate slowly or erratically. To test the pump, you’ll need to measure the pressure output.

• How to Test:
  • Use a hydraulic pressure gauge to measure the pressure at various points in the hydraulic system, including the lift arms and drive motors.
    
  • Compare the results with the manufacturer’s specifications for normal operating pressure.
    
• If the Pump Is Faulty:
  • The pump may need to be replaced or rebuilt.
    
  • Consult with a professional technician to determine the best course of action.
    

Step 5: Inspect the Hydraulic Control Valve
A malfunctioning control valve can cause erratic hydraulic functions or a loss of control over the machine’s attachments.

• How to Inspect:
  • Test the valve operation by activating different hydraulic functions.
    
  • Listen for unusual noises or observe erratic movement of the attachments.
    
• If the Control Valve is Faulty:
  • It may need cleaning, recalibration, or replacement depending on the severity of the issue.
    

Preventive Maintenance Tips for the Bobcat 863 Hydraulic System
Preventive maintenance can help reduce the likelihood of hydraulic issues and ensure that your Bobcat 863 operates efficiently for years. Here are some tips to maintain the hydraulic system:

• Regularly check and maintain hydraulic fluid levels.
  
• Replace filters and clean the hydraulic system regularly to prevent contamination.
  
• Inspect hydraulic hoses and fittings for wear or damage.
  
• Monitor for unusual noises or changes in hydraulic function, which may indicate early signs of trouble.
  

Conclusion
Hydraulic issues in the Bobcat 863 can significantly impact its performance, but with proper troubleshooting and maintenance, most problems can be resolved quickly. By checking fluid levels, inspecting for leaks, testing the hydraulic pump, and maintaining the system regularly, operators can ensure that their machine continues to perform at its best. With these steps, you can keep your Bobcat 863 running smoothly and avoid costly repairs or downtime.