This manual covers the Yanmar 3TNV Series and 4TNV Series Diesel Engines, essential power units for heavy equipment such as Hyundai Mini Excavators (5TON, -7 Series) and Hyundai Skid Steer Loaders. These engines are recognized for their robust design and reliable performance in demanding operational environments. Their diesel technology ensures efficient power delivery and durability, making them a preferred choice for construction and material handling applications. This comprehensive Factory Service/Repair/Workshop Manual provides detailed, step-by-step instructions, complemented by highly detailed exploded pictures and diagrams, to guide users through all aspects of engine maintenance and repair. It covers all repair procedures, including engine specifications, cooling, lubrication, fuel injection, turbocharger service, electrical systems, inspection and adjustment, troubleshooting, service standards, and tightening torques. This resource is designed to assist owners, mechanics, and technicians in effectively maintaining and repairing their Yanmar engines.