This workshop service repair manual covers the Hitachi ZX40U-3 and ZX50U-3 mini-excavators. These machines are engineered for reliability and performance in various construction and landscaping applications. Featuring a robust diesel engine and a hydrostatic transmission, they offer efficient operation and precise control. Their compact size and versatile capabilities make them ideal for tight job sites and demanding tasks. This comprehensive manual provides detailed information essential for the maintenance, repair, and optimal performance of your Hitachi mini-excavator. It includes procedures for routine service, troubleshooting common issues, and in-depth technical specifications. By following the guidelines and instructions within this document, owners and technicians can ensure the longevity and efficiency of the equipment, covering areas such as engine maintenance, hydraulic system service, and operational parameters.