This workshop service manual covers the Mercury Mariner 9.9 HP 4-Stroke outboard engine. Designed for reliable performance, this water-cooled gasoline engine delivers 9.9 horsepower and features a manual or electric start system depending on the specific model. Its robust construction and efficient design make it suitable for a wide range of marine applications, providing dependable power for your boating needs. This comprehensive manual provides detailed information essential for the maintenance, repair, and servicing of your Mercury Mariner outboard. It includes in-depth repair and overhaul procedures, along with technical specifications and guidance on routine maintenance tasks. The information presented is intended to assist owners, technicians, and mechanics in ensuring the optimal performance and longevity of the engine.