This manual covers the 1986 Yamaha Outboard 25ESJ. It is designed to provide comprehensive information for the maintenance and repair of this specific outboard motor model. The manual emphasizes the engineering quality and reliability inherent in Yamaha outboards, offering detailed guidance to ensure optimal performance and longevity.

The scope of this service manual is extensive, encompassing all aspects of repair and maintenance. Key areas covered include general information, periodic inspections and adjustments, fuel system, power unit, lower unit, bracket unit, and the electrical system. Additionally, detailed specifications, troubleshooting guides, and diagnostic procedures are included, along with numerous subsections, wiring diagrams, illustrations, and step-by-step instructions to assist owners, mechanics, and technicians in effectively maintaining and repairing the vehicle.