Komatsu 705-51-20170 Hydraulic Gear Pump | WA250-OC | Dump Truck Parts

The Komatsu 705 Series from LIC Hydraulic is a premium line of External Gear Pumps specifically engineered for Komatsu loaders, excavators, and dump trucks. Models like the 705-51-20170 (commonly used on WA250 units) are built to withstand the rigorous duty cycles of earthmoving environments. These pumps provide the essential flow and pressure required for steering, lifting, and auxiliary hydraulic functions. We provide 100% drop-in replacements, matching original Komatsu mounting patterns, splined shafts, and flow characteristics.

Technical Highlights

• Compatible Models: WA250, WA320, WA380, and various Komatsu Dump Trucks.

• Construction: High-strength aluminum housing with hardened steel gears.

• Pressure Rating: Continuous duty up to 210 bar ($3045\text{ psi}$); Peak up to 250 bar.

• Features: Axial clearance compensation and high-load DU bushings.

Core Advantages

• Optimized Volumetric Efficiency: The floating side plate design ensures minimal internal leakage across a wide range of temperatures, maintaining peak performance even during long shifts in tropical or arctic climates.

• Rugged Reliability: Engineered with high-tensile materials, the 705-51 series is resistant to the cavitation and pressure spikes typical of loader steering systems, extending the time between overhauls.

• Precise Shaft Alignment: The precision-machined splines ensure a perfect match with the engine PTO, reducing vibration and preventing premature wear on the drive coupling.

• Quiet Operation: Advanced tooth profile geometry minimizes fluid pulsation, leading to quieter operation and reduced stress on hydraulic hoses and fittings.

Expert Maintenance Tips

• Seal Replacement: When servicing the pump, always use high-grade NBR or Viton “V-type” shaft seals to prevent environmental contamination and case leakage.

• Oil Cleanliness: Gear pumps are sensitive to abrasive particles. Maintain fluid cleanliness at ISO 19/17/14 to prevent scoring of the pump plates and gear teeth.

• Inlet Inspection: Ensure the suction line is completely airtight. Air ingestion (aeration) will cause rapid pitting of the gears and lead to “whining” noises and loss of pressure.