This service repair manual covers Mercury Mariner Outboard models manufactured between 1987 and 1993. These 2-stroke engines were available in various horsepower configurations, including 70, 75, 80, 90, 100, and 115 HP, with 3-cylinder engines for the lower range and 4-cylinder engines for the higher range. Specific models like the 75 HP Marathon, 75 XD, and 75 Seapro are included. The engines feature oil injection systems and can utilize either carburetion or fuel injection depending on the specific model. This comprehensive English-language manual provides detailed information for the complete tear down and rebuild, maintenance, refurbishment, and restoration of your Mercury Mariner Outboard. It includes essential sections on troubleshooting, technical data such as torque specifications, ignition systems, electrical components including the battery charging and starting systems, and timing adjustments. The manual also covers the cooling system, fuel system, powerhead, lower unit, mid-section, and power trim systems (Design I and II). Furthermore, it details outboard motor installation, engine attachments, and controls like tiller handles and copilot systems.