This document contains chapters about maintenance procedures for hydraulic excavators. Chapter 1 discusses general safety cautions that should be followed when performing maintenance work. It covers correct work practices, safety precautions, preparations, cautions for disassembly/reassembly, and handling hydraulic equipment, piping, seals and hoses. Chapter 2 provides the machine's specifications, dimensions, weights and lifting capacities. Chapter 3 establishes service standards for machine performance, engines, undercarriages, controls, hydraulic equipment and implements. It includes specifications, measurements and corrective actions. Chapter 4 focuses on engine maintenance, covering inspection/adjustment procedures, measurement standards, and reassembly precautions for engine components like the cylinder head, block, valves and fuel injection systems