This manual covers the YANMAR 4LH-TE-HTE-DTE-STE marine diesel engine, a robust and reliable unit designed for demanding maritime applications. Engineered for exceptional performance and longevity, these diesel engines are built to the highest standards, ensuring dependable operation in various marine environments. Their advanced design and quality construction make them a preferred choice for boat owners and operators seeking efficiency and durability. This comprehensive service and repair manual provides detailed information essential for the maintenance and upkeep of your YANMAR marine diesel engine. It includes step-by-step instructions for all repair procedures, routine maintenance schedules, and troubleshooting guidance, supported by clear illustrations and wiring diagrams. This resource is invaluable for owners, technicians, and mechanics to ensure the optimal performance and longevity of the engine.