This manual covers Johnson Evinrude Outboards with 90 HP engines manufactured between 1973 and 1990. These models represent a significant period in outboard motor development, known for their robust engineering and reliable performance on the water. This particular generation of 90 HP outboards was designed to offer dependable power for a variety of boating applications, from fishing to general recreational use. Understanding the intricacies of these engines is key to maximizing their longevity and operational efficiency. The purpose of this Factory Service Repair Manual is to provide comprehensive guidance for the maintenance, repair, and troubleshooting of your Johnson Evinrude 90 HP outboard. It includes detailed procedures for tune-ups, lubrication, and all major systems such as the fuel system, power head, gearcase, and power trim and tilt. With step-by-step instructions, illustrations, and diagnostic techniques, this manual empowers owners and technicians to perform servicing effectively, potentially saving on labor costs and ensuring the continued optimal performance of the outboard motor.