This document provides comprehensive information for the Hitachi Zaxis ZX 225USR-3 excavator, a robust machine engineered for demanding construction and earthmoving applications. Built with precision and reliability in mind, this generation of the Zaxis series features a powerful Isuzu diesel engine delivering approximately 126 kW (169 HP) of power, coupled with a hydrostatic transmission for efficient and responsive operation. Its design prioritizes operational efficiency and durability, making it a dependable choice for a wide range of professional tasks, from excavation to material handling. This Workshop Service Manual, presented in English, serves as an essential resource for maintaining and repairing the Hitachi Zaxis ZX 225USR-3. It covers critical aspects including detailed maintenance procedures, troubleshooting guidance, technical specifications, and vital safety information. With 699 pages of detailed content, this manual is designed to assist owners, technicians, and mechanics in ensuring the optimal performance, longevity, and safe operation of the excavator.