This manual covers Mercury Mariner Outboard Motors manufactured between 1977 and 1989. These versatile engines, ranging from 45 to 200 horsepower, are known for their robust construction and reliable performance in various marine applications. Primarily featuring 2-stroke engine technology with CDI or magneto ignition systems, these outboards utilize carburetors for fuel delivery and water cooling for efficient operation. Many models are equipped with electric starters, and some offer power trim and tilt for enhanced control and maneuverability, alongside forward, neutral, and reverse gear selection through their outboard lower units. The purpose of this Service and Repair Manual is to provide comprehensive guidance for the maintenance, troubleshooting, and repair of your Mercury Mariner outboard motor. It details essential procedures, including recommended fluid types, fuel mixtures, and spark plug specifications, along with information on the cooling system, ignition, and starting mechanisms. This manual serves as an indispensable resource for owners, technicians, and mechanics, ensuring the longevity and optimal performance of these marine propulsion systems.