Comprehensive Guide to Auxiliary Hydraulics on the CAT 315BL Excavator

[MikePhua]

Introduction: The Role of Auxiliary Hydraulics in CAT 315BL
Auxiliary hydraulics on the CAT 315BL excavator are essential for operating a variety of attachments beyond the standard bucket and arm, such as hydraulic breakers, grapples, and augers. These systems expand the machine’s versatility on the job site, allowing operators to perform specialized tasks efficiently. This article provides a detailed overview of the auxiliary hydraulic system on the CAT 315BL, including operation, common issues, troubleshooting, and maintenance tips.
Overview of Auxiliary Hydraulic System Components

• Hydraulic Pump: Supplies pressurized fluid to the auxiliary circuit.
  
• Control Valves: Allow operator regulation of flow and pressure to attachments.
  
• Hydraulic Lines and Hoses: Transport fluid between the pump, valves, and attachments.
  
• Quick Couplers: Facilitate fast and secure attachment connections.
  
• Electric or Mechanical Switches: Enable or disable auxiliary flow from the operator station.
  

Functions and Uses of Auxiliary Hydraulics on CAT 315BL

• Powering hydraulic breakers for demolition.
  
• Operating grapples for material handling.
  
• Running augers for drilling holes.
  
• Controlling hydraulic thumbs for precision gripping.
  
• Driving other hydraulic tools customized for specific tasks.
  

Common Problems and Troubleshooting

• No Auxiliary Flow: Often caused by a closed control valve, faulty switches, or electrical issues.
  
• Insufficient Pressure: Could result from worn pump components, clogged filters, or leaks in hoses.
  
• Erratic Operation: Caused by air in the hydraulic lines or malfunctioning control valves.
  
• Leakage: External leaks from damaged hoses, fittings, or seals.
  
• Attachment Compatibility Issues: Incorrect hose connections or flow/pressure mismatches.
  

Troubleshooting Steps

• Verify the auxiliary hydraulic switch or lever is engaged.
  
• Inspect electrical connections and fuses related to auxiliary hydraulics.
  
• Check hydraulic fluid levels and quality.
  
• Examine hoses and couplers for leaks or damage.
  
• Test system pressure using hydraulic gauges.
  
• Bleed air from the hydraulic system as per manufacturer instructions.
  
• Consult the operator manual for auxiliary flow settings and adjustments.
  

Maintenance Best Practices

• Regularly replace hydraulic filters to prevent contamination.
  
• Inspect and clean quick couplers to ensure proper sealing.
  
• Monitor hydraulic fluid condition and change it at recommended intervals.
  
• Lubricate control valve linkages and switches.
  
• Store hydraulic hoses properly to avoid kinks and damage.
  
• Train operators on correct use of auxiliary hydraulics to prevent misuse.
  

Real-World Example
A contractor using a CAT 315BL for demolition experienced loss of power in the hydraulic breaker attachment. Upon inspection, the auxiliary hydraulic control valve was partially stuck due to contamination. Cleaning the valve and replacing the hydraulic filters restored full function. The operator also began following stricter filter maintenance schedules, preventing repeat problems.
Technical Terms Explained

• Auxiliary Hydraulics: Hydraulic circuits designed to power additional attachments separate from the main boom and bucket functions.
  
• Control Valve: A valve regulating hydraulic flow and pressure to attachments.
  
• Quick Coupler: A device allowing rapid connection and disconnection of hydraulic hoses.
  
• Bleeding Hydraulic Lines: Removing trapped air from the hydraulic system to ensure smooth operation.
  
• Hydraulic Fluid Contamination: Presence of dirt or water in fluid, which can cause wear and malfunction.
  

Conclusion: Maximizing the Utility of CAT 315BL Auxiliary Hydraulics
Auxiliary hydraulics significantly enhance the versatility and productivity of the CAT 315BL excavator. Proper understanding, maintenance, and troubleshooting of the auxiliary hydraulic system ensure reliable operation of attachments, reducing downtime and repair costs. Operators equipped with knowledge about system components and best practices can fully leverage the machine’s capabilities for diverse construction and demolition tasks.