YNF16839 Seal Kit 4640118 ZX330-1 Arm Cylinder Seal Kit with DU Bush Hitachi Excavator Arm Repair Kit

The YNF16839 Arm Cylinder Seal Kit, replacing OEM 4640118, is specially designed for the Hitachi ZX330-1 excavator arm cylinder. This complete repair package includes all critical hydraulic seals required for restoring proper cylinder sealing performance, along with a durable DU bush that enhances the structural support at the arm pivot point. Together, these components help eliminate internal and external hydraulic leakage, smoothen arm operation, and reduce long-term wear at the arm joint.

The seals are manufactured using high-quality PU, NBR, and PTFE to withstand high-pressure workloads and extreme site conditions. The DU bush features a PTFE-lined composite structure that provides excellent lubrication, reduces friction, and prevents premature pin wear. This combined kit is widely used by repair workshops, excavator fleet owners, and aftermarket parts distributors thanks to its durability, compatibility, and cost-effectiveness.