This manual covers the Mercury Mariner 150 HP EFI 4-stroke outboard engine, produced between 2002 and 2007. Engineered for reliability and performance, this engine features Electronic Fuel Injection (EFI) for efficient power delivery and a robust 4-stroke design. Its 150 horsepower output makes it suitable for a wide range of marine applications, offering dependable propulsion for various watercraft. The focus on quality construction ensures consistent operation and longevity for boat owners. The purpose of this Factory Service Repair Manual is to provide comprehensive guidance for the maintenance, repair, and servicing of your Mercury Mariner outboard. It details essential procedures, technical specifications, and troubleshooting steps necessary for optimal engine performance and longevity. This manual is an indispensable resource for owners, technicians, and mechanics, enabling them to perform all necessary upkeep and address potential issues effectively, ensuring the continued reliability and efficiency of the engine.