The Mercury Mariner 25 BigFoot, produced between 1998 and 2008, is a robust 4-stroke outboard engine designed for reliable performance. This model features a 2-cylinder configuration with a displacement of 1.53 L (93.5 cu in), delivering 25 horsepower at the propeller shaft. Its BigFoot designation indicates a specific gear reduction ratio of 2.00:1, optimized for increased torque and thrust, making it suitable for a variety of demanding marine applications. The engine is water-cooled and utilizes a CDI ignition system for efficient operation. This comprehensive Service Repair Manual provides detailed information essential for the maintenance and repair of your Mercury Mariner 25 BigFoot. It covers critical areas including lubrication, fuel system requirements, ignition system specifics, and recommended spark plugs. Additionally, the manual details technical specifications such as bore, stroke, power output, and gear ratios, alongside maintenance procedures and troubleshooting guidance. This resource is designed to assist owners and technicians in ensuring the longevity and optimal performance of the outboard motor.