This service repair manual covers Yamaha outboard engines, specifically models D150H, 175D, 200F, L200F, 200G, and 225D, likely spanning multiple model years. These engines are designed for marine propulsion, offering power outputs ranging from 150 to 225 horsepower. They feature advanced systems such as fuel injection and electronic ignition, along with power trim and tilt for enhanced performance and maneuverability. Built with Yamaha's renowned engineering quality, these outboards are engineered for reliability and durability in demanding marine environments. This manual provides comprehensive guidance for the maintenance, repair, and servicing of your Yamaha outboard engine. It details essential procedures, including recommended service intervals for oil changes, specifications for cooling systems, and information on spark plug types. Technical data, troubleshooting steps, and diagrams are included to assist owners, mechanics, and technicians in keeping the engine in optimal working condition. Adhering to the procedures outlined in this manual will help ensure the longevity and efficient operation of your Yamaha outboard.