This service repair manual covers the Mercury Mariner 90 HP 4-stroke outboard engine manufactured between 2000 and 2005. Engineered for reliability and performance, these outboards are designed for a variety of marine applications. This manual provides essential information to ensure the optimal operation and longevity of your Mercury Mariner engine. The purpose of this comprehensive English-language manual is to guide owners, technicians, and mechanics through all aspects of maintaining and repairing the Mercury Mariner 90 HP 4-stroke outboard. It details periodic maintenance schedules, approved lubricant and parts recommendations, and troubleshooting procedures for common issues. The manual includes step-by-step repair instructions with diagrams, special tool references, tightening torque specifications, and critical safety precautions to ensure all work is performed correctly and safely.