This Service Repair Manual covers Mercury Optimax DFI outboard engines manufactured between 2000 and 2004, encompassing models with horsepower ratings from 75 to 225. These Direct Fuel Injection (DFI) outboards are engineered for robust performance and reliability, offering advanced power delivery through their innovative technology. This manual is designed to provide comprehensive information for these specific engine models, ensuring their optimal operation and longevity. The purpose of this extensive manual is to serve as a definitive guide for the maintenance, repair, and troubleshooting of your Mercury Optimax DFI outboard. It contains detailed instructions, clear illustrations, and color diagrams covering all major components and systems, including the powerhead, fuel system, electrical system, and lower unit. Whether you are a seasoned technician or an owner performing routine maintenance, this manual will equip you with the necessary knowledge and procedures to keep your engine running at peak performance.