321715 OMC RING

Original equipment backup ring component for OMC Johnson/Evinrude outboard piston ring assemblies. Part 321715 functions as a backup ring supporting piston ring sealing operation within the cylinder bore. Genuine OEM piston ring system component used in engine overhaul and ring set assembly on Johnson/Evinrude outboards. Critical internal engine component for compression and blow-by control. Replacement ring available from marine parts specialists; used when performing complete engine rebuild, piston ring replacement, or major overhaul service on Johnson/Evinrude outboard motors.