Caterpillar 287B High Flow Auxiliary Hydraulics Not Working

[MikePhua]

The high-flow auxiliary hydraulic system on the Caterpillar 287B has suddenly stopped working, preventing certain attachments from functioning. This issue is typically related to the hydraulic system and may be caused by insufficient hydraulic flow, system leaks, or faults in other components.
Common Causes

1. Hydraulic Flow Issues
   

The high-flow auxiliary hydraulic system requires a steady hydraulic flow to function correctly. If the hydraulic pump or control valves are malfunctioning, it may result in inadequate hydraulic flow, preventing attachments from receiving enough power.
Solution:

• Check the hydraulic pump to ensure it's functioning properly and providing the necessary flow.
  
• Inspect hydraulic hoses and fittings for leaks.
  

1. Hydraulic Oil Problems
   

Poor-quality hydraulic oil or insufficient oil levels can contribute to reduced system performance. Dirty hydraulic oil can lead to wear and damage of valves and pumps, affecting the overall hydraulic system.
Solution:

• Check the oil level to ensure there is enough hydraulic oil.
  
• If the oil is contaminated or degraded, change it to the correct type and quantity.
  

1. Electrical System Issues
   

The high-flow auxiliary hydraulics are typically controlled by the electrical system. If there is an issue with the wiring or control module, the hydraulic system may fail to operate properly.
Solution:

• Inspect the electrical connections and control switches related to the hydraulic system for loose connections or power loss.
  
• Check the control modules to ensure they are functioning correctly.
  

1. Hydraulic Control Valve Malfunction
   

The hydraulic control valve is a key component that regulates hydraulic flow and pressure. If the valve is stuck or damaged, it could prevent the required flow from reaching the attachments.
Solution:

• Inspect the hydraulic control valve to ensure it's operating correctly.
  
• If the control valve is damaged, repair or replace it as necessary.
  

Troubleshooting Steps

1. Check Hydraulic Oil and Oil Level
   

Start by checking the hydraulic oil level and quality. Ensure that the oil is not contaminated, and that the level is adequate. If the oil is dirty or the level is low, replace and top up the oil as needed.

1. Check Hydraulic System Pressure
   

Use a pressure gauge to test the system’s hydraulic pressure. Ensure it’s within the normal operating range. If the pressure is too low, it may indicate a problem with the pump or other hydraulic components.

1. Check Electrical System
   

Inspect the electrical components related to the hydraulic system. Confirm that control switches, wiring, and modules are functioning properly. If any electrical components are damaged, repair or replace them.

1. Test Control Valve
   

Examine the hydraulic control valve to verify that it is responding to control signals. If the valve is stuck or malfunctioning, repair or replace it.
Conclusion
When the high-flow auxiliary hydraulics on a Caterpillar 287B fail to operate, it is often due to issues with the hydraulic oil, hydraulic flow, control valves, or electrical components. By systematically diagnosing these areas, you can identify the root cause and resolve the issue. Regular maintenance of the hydraulic and electrical systems will help extend the lifespan of the equipment and ensure its efficient operation.