334-9990 K3V280 Hydraulic Main Pump For CAT 385 390 Excavator

This mining grade ultra heavy load high-precision hydraulic main pump assembly has a core original part number of 334-9990 (3349990), and the core adopts Kawasaki's classic K3V280 series ultra large displacement inclined disc high-pressure plunger pump type. As the absolute fluid power heart of the entire system, this assembly is specially designed for Caterpillar's large mining excavators, perfectly matching the 85 to 90 ton absolute main mining giant models such as CAT 385, 385C, 390D, and 390F. The product is optimized based on first principles for ultra-high pressure fluid mechanics, perfectly bearing the overload under extreme all-weather mining conditions, ensuring absolute certainty of high flow power output. The physical dimensions of the product packaging are approximately 980mm × 530mm × 560mm, with an overall net weight of approximately 310kg. The original factory standard position is precisely aligned.

"Extreme cleaning and torque tightening: Before using heavy-duty lifting equipment for docking, the environment needs to be treated with dust removal. All high-pressure oil pipes and feedback signal pipes must be thoroughly cleaned with specialized cleaning agents before being connected to a new pump. Tightening bolts must be carried out using torque wrenches strictly according to the original factory torque for multi-stage symmetrical cross tightening, to prevent uneven stress from causing component cracking.

Forced oil filling (core pit avoidance): After the main pump is lifted into place and before starting the engine, clean hydraulic oil must be filled from the oil injection/exhaust port on the top of the pump body. 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 exhaust transition: After the first ignition, force the engine to idle at low pressure for 15-20 minutes for automatic exhaust and thermodynamic adaptation of the system. After the oil temperature is normal and all bubbles are cleared, gradually apply the working load."