This manual covers Yamaha outboard engines manufactured between 1983 and 1987, specifically the 2-stroke models ranging from 150hp to 220hp. These engines are recognized for their robust engineering and reliable performance, making them a popular choice for various marine applications. This comprehensive guide is designed to provide all necessary information for the upkeep and repair of these powerful units, ensuring their continued operational excellence. The purpose of this English-language service and repair workshop manual is to offer detailed guidance for all maintenance, servicing, and troubleshooting procedures. It includes step-by-step instructions, hundreds of detailed photos, and highly detailed exploded diagrams to facilitate understanding and execution of repairs. This resource is intended for professional mechanics, technicians, and owners seeking to maintain their Yamaha outboard engines, ensuring optimal functionality and longevity.