This manual covers the Mercury Mariner, specifically models produced between 2000 and 2005, featuring the 115 HP DFI Optimax engine. These engines are part of the Optimax DFI Series, known for their Direct Fuel Injection technology. This series represents a significant advancement in outboard engine design, emphasizing efficiency and performance for a wide range of marine applications. The engineering quality and reliability inherent in the Mercury Mariner brand are supported by detailed technical information within this guide. This comprehensive Factory Service Repair Manual, written in English, provides essential information for the maintenance and repair of your Mercury Mariner outboard. It includes hundreds of pages of detailed content, covering all styles and featuring illustrations, diagrams, and photos. Within its pages, you will find step-by-step, numbered instructions for general maintenance, troubleshooting, and in-depth technical procedures for systems such as fuel injection, ignition, electrical, and powerhead. This manual is designed to assist owners, mechanics, and technicians in keeping their engines operating at peak performance and ensuring longevity.