This repair manual covers Mercury Outboard Motors manufactured between 1965 and 1989. These engines, ranging from 90 to 300 horsepower, are known for their robust engineering and reliable performance on the water. This manual provides comprehensive information to ensure your Mercury outboard motor operates at peak efficiency and longevity, reflecting the quality and durability expected from Mercury marine products. The purpose of this manual is to offer detailed guidance on service, maintenance, and overhaul adjustments for Mercury Outboard Motors. It includes essential technical specifications, troubleshooting procedures, and safety guidelines necessary for proper upkeep. Owners, mechanics, and technicians will find the information within this extensive guide invaluable for maintaining and repairing these engines, ensuring continued operational excellence.