The Mercury Mariner 30 Sea Pro is a 2-cylinder, 2-stroke outboard motor designed for reliable performance. With a displacement of 427 cc and an engine bore of 72 mm and stroke of 71 mm, this motor delivers a power output of 30 horsepower, operating within a maximum RPM range of 4500-5500 RPM. Its water-cooled system and CDI ignition ensure efficient operation. This outboard motor is engineered for durability and consistent power delivery, making it a dependable choice for various marine applications. This Workshop Service Manual provides comprehensive guidance for the repair and overhaul of the Mercury Mariner 30 Sea Pro outboard motor. It is intended for a fully conversant technician and covers essential maintenance procedures, including specifications for spark plugs, gearcase oil, and fuel mixture. Detailed technical information on the engine, transmission, and electrical systems is included to facilitate accurate diagnostics and repairs. This manual serves as an indispensable resource for maintaining the optimal performance and longevity of your Mercury Mariner 30 Sea Pro.