This factory service repair manual provides comprehensive technical information for Yamaha F100B and F100C outboard motors. Designed for internal combustion engines, this manual covers all models, engine types, trim, and transmission variations, offering detailed guidance for maintaining and troubleshooting these 100 HP units. Its engineering is focused on reliability and performance, making it an essential resource for ensuring the longevity and optimal function of your Yamaha outboard motor. The purpose of this English-language manual is to serve as a complete guide for service, maintenance, and troubleshooting. It includes step-by-step instructions for complete disassembly, alongside top-quality diagrams and highly detailed exploded illustrations. This resource is suitable for both DIY enthusiasts and experienced mechanics, offering a cost-effective and time-saving solution for keeping your outboard motor in proper working condition, mirroring the standards used in professional service shops.