The Hitachi Zaxis 270-3 and Zaxis 270LC-3 hydraulic excavators represent the third generation of these robust machines, engineered for demanding construction and earthmoving applications. Powered by a reliable Cummins QSB6.7 diesel engine, these excavators deliver robust performance with a net power output of 144 kW (193 hp) at 2000 rpm, meeting Tier III / Stage IIIA emission standards. Their design emphasizes durability and efficiency, featuring a hydrostatic drivetrain with two-speed variable displacement travel motors for precise maneuverability. With an operating weight ranging from approximately 26,000 to 27,500 kg, and dimensions optimized for stability and reach, including a standard boom length of 5.7 meters and a bucket capacity of 1.35 m³, these excavators are built to tackle a wide array of tasks. This comprehensive Workshop Service Manual provides essential information for the proper maintenance and repair of the Hitachi Zaxis 270-3 and Zaxis 270LC-3 hydraulic excavators. It covers critical areas such as detailed maintenance procedures, diagnostic troubleshooting guides, and in-depth technical specifications for all major systems, including the engine, transmission, and hydraulic circuits. Safety guidelines and operational best practices are also included to ensure the longevity and optimal performance of the equipment. This manual is an indispensable resource for owners, operators, mechanics, and technicians seeking to understand, maintain, and service these advanced machines effectively.