This manual covers Mercury Mariner outboard motors manufactured between 1990 and 2000, encompassing a wide range of models from 2.5 horsepower to 275 horsepower. These two-stroke engines are renowned for their robust performance and reliability, making them a popular choice for various marine applications. This guide provides comprehensive information for maintaining and repairing these dependable outboard powerplants, ensuring optimal operation for years to come. The purpose of this manual is to serve as an authoritative resource for owners, technicians, and mechanics. It details essential maintenance procedures, troubleshooting guides, technical specifications, and safety guidelines specific to the covered Mercury Mariner outboard models. By following the instructions within this guide, users can effectively perform routine service, diagnose issues, and complete repairs, thereby extending the lifespan and preserving the performance of their outboard motor.