This manual covers the Mercury Mariner 30/40 (2 Cylinder) outboard engine. Designed for reliable performance, this gasoline-powered, water-cooled engine features a CDI ignition system and an outboard gearcase with forward-neutral-reverse gears and propeller shaft drive. Its robust engineering ensures dependable operation for a variety of marine applications. This comprehensive Service Repair Manual in English provides detailed information for the maintenance and repair of your Mercury Mariner outboard. It covers essential procedures, technical specifications, and guidelines necessary for owners and technicians. Utilizing this manual will help ensure the longevity and optimal performance of your engine.