This document pertains to the Yanmar 6LYA-STE, a robust diesel engine renowned for its engineering quality and reliability. Designed for demanding applications, this inline 6-cylinder engine features direct injection and a water-cooled system, ensuring efficient and dependable operation. Its forced lubrication system contributes to longevity, making it a trusted choice for various operational needs. This Factory Service Repair Manual, provided in English, offers comprehensive guidance for maintaining and repairing the Yanmar 6LYA-STE. It covers a wide range of procedures, including maintenance, repair, rebuild, refurbish, and restore operations, presented in a step-by-step format suitable for a factory-trained technician level. The manual includes detailed information on basic engine parts, fuel injection, intake and exhaust systems, lubrication, cooling, electrical, and remote control systems. Advanced troubleshooting guides, numerous illustrations, and diagrams are included to assist in diagnosis and correction, enabling owners and technicians to effectively manage and service the engine.