This document pertains to the Yamaha 40EJRS, a 40 horsepower two-stroke outboard motor manufactured in 1994. Designed for marine propulsion, this water-cooled engine utilizes a gasoline fuel system and a CDI ignition. Yamaha is renowned for its engineering quality and the reliability of its marine products, and this model exemplifies their commitment to robust performance for a wide range of boating applications. This Factory Service Manual in English provides comprehensive guidance for the maintenance and repair of the Yamaha 40EJRS outboard motor. It covers essential areas including general information, periodic inspections and adjustments, fuel system, power unit, lower unit, bracket unit, and the electrical system. The manual includes detailed step-by-step instructions, diagnostic procedures, and technical specifications, supported by detailed wiring and circuit diagrams, illustrations, photos, and exploded views. This resource is invaluable for owners, mechanics, and technicians seeking to ensure the optimal performance and longevity of their marine propulsion system.