This service manual covers the Mercury Mariner 4-Stroke Outboard models manufactured between 2000 and 2001. These outboards are engineered for reliability and performance, featuring a DOHC engine configuration and Multi-point Sequential Electronic Fuel Injection for efficient power delivery. Available in 75HP and 90HP variants, they are designed for a variety of marine applications, offering robust construction and dependable operation. This comprehensive manual provides detailed information essential for the maintenance, repair, and troubleshooting of your Mercury Mariner outboard. It includes maintenance charts, procedures for filter changes, water pump impeller replacement, and thermostat operation. Furthermore, the manual offers in-depth guidance on electrical system service, ignition timing adjustments, EFI component service, and troubleshooting the entire system. Technical specifications, including tightening torques, cylinder compression, engine oil pressure, idle speed, and wide-open throttle RPM, are also provided, along with exploded views and wiring diagrams to aid in diagnostics and repairs.