Outboard. Motor. The aquot;really quietaquot; Johnson Sea-Horse 5%, winner of the National Noise Abatement Council award, represents one of ... Other developments include production of an electric-starter 25 hp. outboard and re- engineering of the Sea-Horse 10 to include ... The following models were among those exhibited: Model DIX4E, 4 cylinder, 75 hp.; Model DIX4ES, 4 cylinder, 95 hp.; Model DIX6E.