This Service Repair Manual covers the Mercury Mariner outboard motor. This motor is a 2-stroke, water-cooled unit with a CDI ignition system and carburetor fuel induction, producing 2.5 horsepower. It is designed for use with unleaded gasoline mixed at a 50:1 ratio of gasoline to oil, and features a tiller handle with twist grip throttle control. The Mariner outboard motor is engineered for reliable performance and efficient operation, making it a dependable choice for various marine applications. This manual provides comprehensive guidance for the maintenance, repair, and technical understanding of the Mercury Mariner outboard motor. It details essential procedures for lubrication, including the recommended 2-stroke outboard oil and marine gear lubricant. Technical specifications and troubleshooting information are included to assist owners, mechanics, and technicians in ensuring the optimal performance and longevity of the motor. The content is presented in English to facilitate clear communication and effective service.