This workshop repair service manual covers Mercury Mariner outboard motors, featuring a gasoline-powered, water-cooled engine with a 125 horsepower output and a CDI ignition system. Designed for marine applications, these engines are known for their robust construction and reliable performance on the water. The manual provides comprehensive information to ensure optimal operation and longevity of your Mercury Mariner outboard. This manual serves as an essential guide for all service, maintenance, and troubleshooting procedures. It details critical aspects such as lubrication, fuel system maintenance, cooling system upkeep, and electrical system specifications. By following the instructions and guidelines within this document, owners, mechanics, and technicians can effectively maintain and repair their Mercury Mariner outboard motors, ensuring continued operational efficiency and safety.