This manual covers the Yamaha 150ETXD outboard motor, manufactured in 1990. Designed for marine propulsion, this 2-stroke gasoline engine delivers 150 horsepower. Yamaha is renowned for its commitment to engineering excellence, ensuring robust performance and lasting reliability in demanding marine environments. This outboard motor is built to provide dependable power for a variety of boating applications, reflecting Yamaha's dedication to quality and innovation in marine technology. The purpose of this English-language digital manual is to provide comprehensive guidance for the service, repair, and maintenance of the Yamaha 150ETXD outboard motor. It includes detailed, step-by-step procedures for disassembly, assembly, and repair, supported by comprehensive inspection operations and exploded diagrams. This resource is designed to assist owners, mechanics, and technicians in effectively maintaining the motor's optimal performance and longevity, ensuring it remains a reliable component for all marine propulsion needs.