This service repair manual covers the Mercury Mariner SeaPro outboard motor, specifically the 3.0L variant. This powerful V6 engine features fuel injection and a water-cooled system, designed for robust performance and reliability in marine applications. While specific production years are not detailed, this manual addresses a range of models within the 3.0L SeaPro series, providing essential information for owners and technicians. The Mariner SeaPro is engineered for demanding use, offering a dependable power source with a typical output of 150-200 horsepower. The purpose of this manual is to provide comprehensive guidance for the maintenance, repair, and technical understanding of the Mercury Mariner SeaPro 3.0L outboard motor. It details crucial procedures, including routine servicing, fluid capacities, ignition system maintenance, and fuel system requirements. Technical specifications, troubleshooting steps, and information on the hydraulic trim and tilt system are also included. This resource is invaluable for ensuring the optimal performance, longevity, and safe operation of your Mercury Mariner SeaPro engine.