8106487 Original Excavator Hydraulic Main Pump Cylinder Block Rotor for ZX670-5B ZX690-5A ZX870-5G Z

This original high-precision hydraulic main pump cylinder rotor is custom-designed for the hydraulic systems of **Hitachi (HITACHI)** medium and large-sized excavators. Manufactured strictly according to official part number **8106487**, it perfectly matches the main piston pumps of Hitachi's ZX200-3, ZX240-3, and ZX330-3 main models. As the rotating core for power conversion, this component features precise physical interfaces and micron-level tolerances, allowing for seamless assembly with original plungers and distributor plates, helping the main pump restore efficient system coordination under extreme operating conditions.

This cylinder rotor is made of high-purity special wear-resistant alloy steel, undergoing precision integral forging and digital multi-axis precision milling. The core contact surfaces undergo deep quenching and special grinding treatment, giving them both "external hardness and internal toughness" mechanical properties—the cylinder bore mating surfaces have extremely high hardness, possessing excellent anti-adhesion and anti-cavitation properties; the rotor matrix has high fatigue strength and can effectively withstand ultra-high pressure alternating loads. The product has passed rigorous high-pressure sealing and dynamic balancing tests, exhibiting absolute physical rigidity and extremely low losses during high-speed rotation.

When replacing the rotor during a major overhaul of the main pump, assembly must be performed in an absolutely dust-free **low-entropy environment**. Before assembly, the hydraulic lines must be thoroughly cleaned, and the hydraulic oil and filter element must be replaced. During the initial operation phase, the main pump should be purged first; dry running is strictly prohibited. During routine maintenance, the pressure, oil temperature, and return oil cleanliness of the hydraulic system must be closely monitored. If any abnormal oil quality or unusual pump noise is detected, the machine should be stopped immediately for inspection. Establishing a standardized hydraulic system maintenance log and maintaining a high degree of purity of the medium ensures that the rotary pump core remains in a stable service condition for a long period.