This Service Repair Manual covers the Mercury MerCruiser 3.0L WORK sterndrive engine, including the 225 EFI and 250 EFI variants, starting from model year 2002 with serial number 0T409000. This V-6 cylinder, two-cycle engine features a loop-charged aspiration system and Electronic Fuel Injection (EFI), delivering 225 HP or 250 HP. Engineered for reliability and performance, these engines are designed for demanding marine applications. This manual provides comprehensive guidance for the maintenance, repair, and troubleshooting of your Mercury MerCruiser 3.0L WORK engine. It details essential procedures, technical specifications, and safety precautions necessary to ensure optimal performance and longevity. Whether you are a boat owner performing routine maintenance or a technician undertaking complex repairs, this manual serves as an indispensable resource for understanding and servicing your engine.