If your replacement impeller is smaller than the original 434424 one, it’s probably a later 763735 impeller meant for the water pumps with a plastic housing which were used on the ’79 six horse motors. These pumps will fit any 5.5 or 6 horse motor from ’54 – ’79 and the complete kit is P/N 763758 and are standard replacement now for the older pumps with a metal housing.
