This service repair manual covers Yamaha 25BMH and 30HMH outboard motors. Designed for vehicle repair and maintenance, these motors are engineered for reliability and performance. This manual provides comprehensive information to ensure your Yamaha outboard motor operates at its peak efficiency. This manual offers detailed instructions for a wide range of maintenance and repair procedures. It includes general information, specifications, periodic checks and adjustments, fuel system, power unit, lower unit, bracket unit, and electrical system details. Troubleshooting guides and wiring diagrams are also provided to assist both do-it-yourself enthusiasts and experienced mechanics in understanding and servicing these outboard motors.