321504 OMC SEAL CRANK SHAFT UPPER

OEM OMC Johnson/Evinrude crankshaft upper seal (321504) prevents oil leakage at the upper crankshaft journal. This dynamic seal maintains engine compression and oil retention during operation. Compatible with most OMC Johnson/Evinrude outboard motors and sterndrive engines across multiple displacement and model years. Replace during engine rebuilds or if visible oil seepage appears at the crankshaft. Standard replacement maintains original equipment reliability.