This service repair workshop manual covers the MERCURY Mariner OUTBOARD FOUR STROKE outboard motor. Designed for reliability and performance, these four-stroke engines, including the BIGFOOT variant, are available in 40HP, 45HP, and 50HP configurations. This manual is applicable to models from 1999 onwards, providing comprehensive information for maintaining and operating your Mercury outboard motor. This manual offers detailed step-by-step instructions, hundreds of pages with detailed photos and diagrams, and highly detailed exploded diagrams to guide you through all repairs, servicing, and troubleshooting procedures. It is an essential resource for owners, mechanics, and technicians seeking to ensure the optimal performance and longevity of their Mercury Mariner outboard motors.