This service repair manual covers the Yamaha 4HP Outboard models produced between 1996 and 2009. These reliable outboard engines, featuring a 4 HP (2.9 kW) power output, water-cooled systems, and CDI ignition, are designed for a variety of marine applications. The manual encompasses both 2-stroke and 4-stroke variants, utilizing carburetor fuel delivery and offering F-N-R shift controls. Known for their engineering quality and dependability, these Yamaha outboards are a popular choice for boaters seeking robust performance. This comprehensive English-language manual provides detailed information essential for maintaining and repairing your Yamaha 4HP Outboard. It includes step-by-step repair instructions, periodic maintenance schedules, lubrication guidelines, tune-up procedures, and an advanced troubleshooting guide with diagnostic tests. With numerous diagrams and pictures, this manual serves as an invaluable resource for owners, mechanics, and technicians, ensuring the longevity and optimal performance of models such as 4MHU, F4X, and many others listed within.