This Service Repair Manual covers the YANMAR 4LHE Marine Diesel Engine, an internal combustion engine designed for marine propulsion. Engineered for reliability in demanding marine environments, this diesel engine is a robust solution for various maritime applications. Its advanced design and YANMAR's commitment to quality ensure dependable performance for boat owners and operators. This comprehensive manual provides essential information for maintaining and repairing your YANMAR 4LHE engine. It includes detailed step-by-step repair procedures, troubleshooting guides, periodic checks and adjustments, and coverage for all engine systems, including fuel, lubrication, cooling, combustion, and electrical systems. Highly detailed exploded diagrams and wiring schematics are also included, making it an invaluable resource for owners, mechanics, and technicians to ensure optimal engine operation and longevity.