This Service Repair Manual covers the 1994 Mercury Mariner 90 HP outboard motor, identified by serial number 0D283222 and above. This robust 3-cylinder inline engine delivers 90 horsepower, featuring a 2.0-liter displacement and a carbureted fuel induction system. Engineered for reliability and performance, this water-cooled motor is designed to provide dependable power for a variety of marine applications. Its construction emphasizes durability and efficient operation, making it a capable choice for demanding aquatic environments. The purpose of this manual is to provide comprehensive guidance for the maintenance, repair, and technical understanding of your Mercury Mariner 90 HP outboard motor. It details essential procedures for routine servicing, including lubrication, fuel system care, and spark plug specifications. Additionally, the manual offers in-depth technical information, troubleshooting advice, and specifications to assist owners, mechanics, and technicians in ensuring optimal performance and longevity of the engine. This resource is designed to facilitate effective upkeep and repair.