This manual covers 45-115 HP 2-Stroke Outboard engines manufactured between 1965 and 1989. These versatile marine engines, available in a range of horsepower from 45 to 115, were designed for a variety of boating applications. They feature robust 2-stroke technology, water-cooling systems, and are primarily carbureted, often utilizing either a mixed fuel/oil system or an oil injection setup. The engine configurations vary across the model years and horsepower ratings, including inline 2, 3, and 4-cylinder designs, as well as V4 configurations, with displacements ranging significantly to meet diverse performance needs. This comprehensive service manual provides essential information for the maintenance and repair of your outboard. It includes detailed procedures for routine maintenance, engine specifications, fuel and lubrication systems, cooling systems, electrical systems, and the outboard lower unit. Furthermore, the manual offers advanced troubleshooting guidance, covering engine removal and installation, steering systems, and bodywork. This resource is invaluable for owners, technicians, and mechanics seeking to ensure the optimal performance, reliability, and longevity of their 45-115 HP 2-Stroke Outboard engines.