KYB PSV2-66T Main Pump | 20640-44015 20640-44013 | Sumitomo SH265 Excavator

The KYB PSV2-66T Series Main Pump from LIC Hydraulic is the high-performance core of the Sumitomo SH265 excavator series. Engineered to handle the demanding duty cycles of 25-ton class machinery, this tandem axial piston pump (Part Nos. 20640-44015 and 20640-44013) provides synchronized power for travel, swing, and front-end attachments. Our units are manufactured to the highest Japanese engineering standards, ensuring 100% drop-in compatibility with original equipment regarding mounting flanges, splined shafts, and hydraulic interfaces.

Technical Highlights

• Series: PSV2-62T, PSV2-63T, PSV2-66T, PSV2-66T-2.

• Max Pressure: Continuous duty up to $343\text{ bar}$ ($4975\text{ psi}$), Peak $390\text{ bar}$.

• Design: Tandem Variable Displacement Piston Pump with high-sensitivity regulators.

• Machine Fit: Specifically optimized for Sumitomo SH265 series excavators.

Core Advantages

• Dynamic Flow Distribution: The tandem design allows for independent control of multiple hydraulic circuits, enabling smooth combined movements such as simultaneous boom lifting and arm crowding without power loss.

• Energy Efficiency: The integrated regulators utilize advanced negative flow control logic, reducing displacement during idle periods to minimize fuel consumption and oil temperature rise.

• Hardened Rotating Groups: Featuring precision-lapped valve plates and heavy-duty piston assemblies, the PSV2-66T is built to resist wear from thermal cycling and fine particulate contamination.

• Reliable Cold Start Capability: Designed with optimized internal lubrication paths, the pump establishes system pressure rapidly even in low-temperature environments, protecting critical components from dry-start friction.

Expert Maintenance Tips

• Regulator Adjustment: Do not attempt to adjust the regulator settings without a proper pressure gauge and the official Sumitomo service manual. Incorrect settings can cause engine stalling or sluggish hydraulic response.

• Oil Cleanliness: To maintain the precision tolerances of the KYB PSV2 series, ensure hydraulic fluid cleanliness at ISO 18/16/13. Always use high-quality 10-micron filters.

• Pilot Pressure Check: Sluggish performance is often caused by low pilot pressure or a clogged pilot filter rather than the main pump itself. Always verify pilot system integrity before replacing a main pump unit.