The Hitachi Zaxis 240-3 is a robust hydraulic excavator from the Zaxis 3 Series, engineered for demanding construction and earthmoving applications. This model, powered by an Isuzu 6HK1-XQA direct injection, water-cooled, 4-cycle diesel engine, delivers 174 HP (129 kW) and meets EPA Tier 3 / EU Stage III emission standards. Its hydrostatic transmission provides efficient power delivery with travel speeds up to 5.5 km/h, while its substantial operating weight of 23,600 kg and impressive digging capabilities, including a maximum digging depth of 6,670 mm and a standard bucket capacity of 1.0 m³, underscore its suitability for heavy-duty tasks. The Zaxis 240-3 is designed for reliability and performance in challenging environments. This Workshop Service Manual (WSM) provides comprehensive technical information for the Hitachi Zaxis 240-3 hydraulic excavator. It covers essential maintenance procedures, detailed troubleshooting guides, and critical technical specifications, including engine, transmission, and hydraulic system data. With an emphasis on clarity and accuracy, this manual is an indispensable resource for owners, mechanics, and technicians. Its in-depth content ensures that the Zaxis 240-3 can be maintained and repaired effectively, maximizing its operational lifespan and performance.