This manual covers Yamaha outboard motors with horsepower ranging from 100 to 140 HP, specifically for model years 1999 through 2003. These engines are engineered for reliable performance in various marine applications. This comprehensive guide provides detailed information to ensure optimal operation and longevity of your Yamaha outboard motor. This Repair Service Technical Maintenance Manual is designed to assist owners, technicians, and mechanics in performing all necessary maintenance, service, and repair tasks. It includes detailed sections on periodic inspections, fuel systems, power units, lower units, bracket units, electrical systems, and troubleshooting. With 352 pages of technical data, this manual is an essential resource for keeping your Yamaha outboard motor in peak condition.