Jabsco 6303-0003-P, Nitrile, Drive Type 4, 6 Blade, 2 Diameter, 7/8 Width, 5/16 Shaft, Plastic Insert Replace all impellers at least once every year or sooner, depending on the engine duty Always carry spare impellers on board in case of emergency, it is one of the most vital components of the engine cooling system and should always be treated as such Always grease new impellers, makes it easier to install the impeller onto the pump bore and gives added protection to the impeller during initial prime