The Mercury MerCruiser 8.1L 496 CID engine family represents a robust line of petrol engines designed for marine applications. This manual covers sterndrive models, including the 496 Mag HO and 496 Mag, as well as inboard models such as the 8.1S HO and 8.1S Horizon, all from serial number 0M000000 and up. Engineered for reliability and performance, these engines are built to provide a powerful and dependable boating experience. This comprehensive Service Repair Manual provides essential information for the maintenance and repair of your Mercury MerCruiser 8.1L 496 CID engine. It includes detailed instructions, illustrations, and diagrams covering general information, maintenance schedules, troubleshooting procedures, and specific system overhauls such as the starting, ignition, charging, fuel, cooling, exhaust, and power steering systems. The manual is designed to assist both do-it-yourself owners and experienced mechanics in keeping their vessel in optimal condition.