This service repair manual covers the Komatsu 102 Series Diesel Engine, specifically models 102E-1 and 102E-2. These engines are known for their robust construction and reliable performance, making them a staple in various heavy-duty applications. Engineered for durability and efficiency, the Komatsu 102 Series engines are integral components in a wide range of machinery, including excavators, bulldozers, wheel loaders, motor graders, mobile crushers, crawler carriers, vibratory rollers, and generators. Their design prioritizes operational longevity and power output, ensuring consistent performance across demanding work environments. This comprehensive English-language manual provides detailed information essential for the maintenance, repair, and servicing of the Komatsu 102 Series Diesel Engine. It includes sections on general information, structure and function, testing and adjusting, disassembly and assembly, maintenance standards, and repair and replacement of parts. With detailed diagrams and photo illustrations, this manual serves as an indispensable resource for owners, mechanics, and technicians, enabling them to perform all necessary service operations accurately and efficiently, thereby ensuring the optimal performance and extended lifespan of the engine and the equipment it powers.