Replacement for stock cast-iron, plastic and aluminum composite water pumps. Made of bronze and stainless steel, this pump withstands harsh, corrosive marine environments. 1-piece body makes occasional impeller or seal replacement easy. Includes replaceable cam and wearplate so that pump can be overhauled to like-new condition. Replaces: Mercruiser 46-72774-A32. Takes impeller 179540001.