Hitachi EX20UR-2 / EX30UR-2 / EX40UR-2 Excavator Workshop Manual

• Official 388-page OEM publication (KM-584E-00 / W584E-00), originally released in 1994 by Hitachi Construction Machinery Co., Ltd.
• Master reference for professional workshops and owners servicing canopy, upperstructure, and undercarriage systems on the EX20UR-2, EX30UR-2, and EX40UR-2 excavator line.
• Contains 46 detailed exploded-view diagrams illustrating component assemblies to support accurate repair planning and parts identification.
• Features 14 torque-specification tables for exact fastening precision during mechanical overhauls.

Component and System Documentation

This workshop manual structures information by critical equipment section to speed up navigation through the upperstructure and undercarriage assemblies. You will find comprehensive assembly and disassembly sequences for key components. These include the main pump, swing device, and control valve configurations. To ensure accurate reassembly, each chapter presents specific exploded diagrams that identify internal parts like spools, valve plates, needle bearings, and planetary gear sets. Instead of generic overviews, the text maps model-specific data directly to the hardware. This highlights the exact mechanical variances between the three units to improve service accuracy on the shop floor.

Specification and Reference Values

Precise metrics take the guesswork out of heavy machinery maintenance. The documentation offers exact baseline numbers for the entire series, such as the 109 N·m torque requirement for swing bearing mounting bolts. Model-specific data is also broken down clearly; for example, the EX30UR-2 lists a 42-liter hydraulic tank capacity and a 27 kg swing device weight. Mechanics can reference these extensive data tables to confirm load capacities, fluid fill levels, and critical bolt tightening requirements prior to any major repair. Always consult a certified heavy equipment technician and review standard shop safety protocols before beginning work on pressurized hydraulic systems or heavy structural components.