This manual covers the Mercury Mariner outboard motor, a reliable and efficient power unit designed for a variety of marine applications. Featuring a robust two-stroke engine with 9.9 horsepower and a CDI ignition system, this motor is engineered for dependable performance. Its water-cooled design and through-propeller hub exhaust system contribute to its operational efficiency and quiet running. The Mariner outboard is built with Mercury's commitment to quality, ensuring durability and ease of operation for boaters. This comprehensive Workshop Service Repair Manual provides essential information for the maintenance and repair of your Mercury Mariner outboard motor. It details crucial procedures, including lubrication with recommended oil and a 50:1 mixing ratio, spark plug specifications, and electrical system information. Technical specifications cover engine details, transmission, and shaft length options, while maintenance sections guide users through routine servicing. This manual is an indispensable resource for owners and technicians aiming to keep the motor in optimal working condition.