The Hitachi ZAXIS 27U/30U/35U series represents a line of compact excavators designed for versatile operation in various construction and landscaping applications. These tracked machines feature a hydrostatic transmission and are powered by efficient diesel engines, with displacements and power outputs varying by specific model configuration. Engineered for reliability and performance, the ZAXIS series offers robust construction and a focus on operator comfort and safety, including a ROPS-compliant operator station. Their compact size and maneuverability make them ideal for tight job sites, while their operational weight typically ranges from 2.7 to 3.5 metric tons, enabling efficient material handling and excavation tasks with bucket capacities generally between 0.07 and 0.12 cubic meters. This Service Repair Manual provides comprehensive guidance for the maintenance, repair, and technical understanding of the Hitachi ZAXIS 27U/30U/35U excavators, covering serial numbers 007001 and up. The manual details essential procedures, including routine maintenance schedules, engine oil and hydraulic oil capacities, and critical technical specifications for performance and components. It serves as an indispensable resource for owners, mechanics, and technicians, offering in-depth information on troubleshooting, system diagnostics, and repair methodologies to ensure the optimal performance, longevity, and safety of the equipment.