This comprehensive service and repair manual provides detailed instructions and high-quality diagrams for maintaining and repairing your Mercury Outboard motor. It covers a wide range of models, including the 70, 75, 75XD, 75 Seapro, 80, 90 (3-Cylinder) for years 1987 to 1993, and the 100 and 115 (4-Cylinder) for years 1988 to 1993. The manual's content is organized into sections that address various aspects of your outboard motor, ensuring you have the information you need to tackle any repair or maintenance task. You'll find detailed instructions on: * General information and specifications * Electrical and ignition systems, including battery, charging, and starting systems, along with timing and synchronizing adjustments and wiring diagrams * Fuel systems and carburetion * Oil injection systems * Powerhead components for both 3-cylinder and 4-cylinder engines * Lower unit, including gear housing, mid section, and shock absorber * Power trim systems, encompassing both Design I (side fill reservoir) and Design II (aft fill reservoir), as well as single ram configurations * Outboard motor installation and attachments, covering engine installation, tiller handle setup, and co-pilot configurations. This manual is an invaluable resource for anyone seeking to perform DIY repairs and maintenance on their Mercury Outboard motor. It offers step-by-step guidance and clear illustrations, making it an essential tool for achieving successful outcomes.

The 1987-1993 Mercury 70-115 HP 2-stroke 3-cylinder outboard motors were a popular choice for fishing and recreational boating during their production run. These engines are known for their durability, reliability, and relatively simple design. All models in this range shared a common 2.0L displacement, inline 3-cylinder design, and featured a variety of features depending on the specific horsepower rating. The 70HP model was the entry-level option, while the 115HP offered the most power. These engines were available in both standard and "SeaPro" versions, the latter being designed for heavier use and more demanding conditions. The "XD" model designation denoted a specific configuration featuring a larger carburetor and higher compression ratio for increased performance. Despite their age, these Mercury outboards remain relatively common and are still prized by boat owners for their ruggedness and accessibility. Their simplicity makes them relatively easy to maintain, and there are still a wealth of parts and resources available for these engines. The mechanical simplicity of the 2-stroke design, while requiring more frequent oil changes, also makes them generally less prone to major failures than their newer 4-stroke counterparts. However, their fuel efficiency and emissions standards are significantly lower than modern outboards. The 1987-1993 Mercury 70-115 HP 2-stroke 3-cylinder outboards offer a robust and reliable option for anyone looking for a classic and powerful outboard motor. However, prospective buyers should be aware of their age and the potential for requiring parts or repairs.