CAT 251-8031 Hydraulic Piston Pump

This high-end heavy-duty high-precision hydraulic power unit features Caterpillar original core component numbers 251-8031 and 207-4708, while also seamlessly compatible with replacement codes 251-8030 and 382-6573, ensuring perfect platform interchangeability across generations of components. The high-pressure plunger pump assembly is specifically engineered for Caterpillar's wheeled hydraulic excavators, precisely matching the CAT M315D and other industry-leading 15-ton class wheeled excavator models. Based on first principles, the product optimizes the swash plate plunger architecture and dual full-power oil flow (Optimized Oil Flow), flawlessly handling the unique high-frequency travel maneuvers, high-torque braking, and dynamic digging loads typical of wheeled operations, guaranteeing absolute power output certainty. The product packaging measures approximately 620mm × 340mm × 370mm, with an overall net weight of about 95kg.

"Extreme cleaning and torque tightening: Before using heavy-duty lifting equipment for docking, the installation surface of the engine flywheel housing and the transmission spline shaft must be kept absolutely clean. All high-strength fastening bolts must be tightened using torque wrenches, strictly following the original factory torque standards for symmetrical and multi-stage cross tightening, to prevent local abnormal shear stress from causing slight stress deformation of the shell.

Forced oil injection (core pit avoidance): After the main pump is lifted into place and the pipeline connection is completed, clean hydraulic oil must be filled from the top oil injection/exhaust port of the main pump and manually turned before starting the engine for the first time. It is strictly prohibited to start dry grinding, otherwise the internal rotating components will undergo irreversible physical erosion within 3 seconds of ignition.

Low pressure transition and full exhaust: After the first ignition, the engine must be kept idling and running at low pressure for 10-15 minutes for automatic exhaust of the entire system. The working device and walking mechanism should be controlled to perform slow and full stroke reciprocating actions. After confirming that there are no bubbles and the pressure is stable, normal operating loads can be gradually applied."