310584 OMC O-RING

The OMC Johnson/Evinrude 310584 is an o-ring seal positioned between the impeller and driveshaft in water pump assemblies. This elastomer component prevents water leakage and maintains pressure in the cooling system of OMC, Johnson, and Evinrude outboard motors. Used across multiple engine generations from the 1960s through 2000s. Part of many water pump repair kits and available through marine suppliers. Standard replacement interval recommended every 5-10 years depending on usage.