K3V280 Hydraulic Main Piston Pump for Hitachi EX3600-5 / EX3600-6 / EX8000-6 Excavators The K3V280 hydraulic main piston pump is engineered for the demanding duty cycles of Hitachi EX3600-5, EX3600-6, and EX8000-6 mining excavators. Compatible with part numbers 4422386 , YA00003085 , 4689080 , and 4624104 , this pump assembly delivers the high flow and pressure stability required for continuous heavy-load mining operations. Key Specifications Operating Weight 352 t (backhoe)