This workshop service repair manual covers the Mercury Mariner 30JET HP outboard motor, a 4-cylinder, 2-stroke engine designed for marine propulsion. With a displacement of 496cc and a horsepower of 30 HP, this water-cooled engine features a carbureted fuel system and CDI ignition. Its robust engineering ensures reliable performance for a variety of boating applications. The transmission offers Forward-Neutral-Reverse functionality with a 2.15:1 gear ratio, complemented by various propeller options for optimized performance. This comprehensive official factory manual provides detailed guidance for the maintenance, repair, and servicing of your Mercury Mariner outboard motor. It includes essential information on lubrication, tune-up procedures, electrical systems, and technical specifications. Owners, mechanics, and technicians will find the step-by-step instructions and diagnostic information invaluable for ensuring the longevity and optimal operation of the engine. The manual is presented in English and contains hundreds of pages of detailed content.