Product Overview This hydraulic swing motor assembly is the core rotating drive component of an excavator, compatible with the E320B and E330B models. It delivers torque for upper-structure rotation and integrates the hydraulic motor with the reduction gear unit. Precision machining ensures stable rotating output and reliable sealing performance, making it well suited for equipment overhaul and replacement. Interchange Part Numbers 116-3550 116-3549 107-7054 Common Faults