This comprehensive shop manual provides detailed service information, step-by-step repair instructions, and maintenance specifications for the Komatsu PC400-6, PC400LC-6, PC450-6, and PC450LC-6 hydraulic excavators. Designed to enhance the quality of repairs, this manual offers a thorough understanding of the product and guides technicians through proper repair procedures and decision-making. **Applicable Models:** * Komatsu PC400-6 Hydraulic Excavator SN: 32001 and up * Komatsu PC400LC-6 Hydraulic Excavator SN: 32001 and up * Komatsu PC450-6 Hydraulic Excavator SN: 12001 and up * Komatsu PC450LC-6 Hydraulic Excavator SN: 12001 and up **Engine Information:** * Komatsu PC400, 450-6 models are equipped with the SA6D125-2 engine. * For detailed engine information, refer to the 125-2 Series Engine Shop Manual. **Manual Content:** The manual is organized into chapters for each major component group and further divided into sections for clarity and ease of use. **Structure and Function:** This section provides in-depth explanations of the structure and function of each component, serving as a valuable resource for troubleshooting and understanding the overall design. **Testing and Adjusting:** This section outlines the necessary checks before and after repairs, including adjustments required upon completion. Troubleshooting charts that correlate problems with potential causes are also included for efficient diagnostics. **Disassembly and Assembly:** Detailed procedures for removing, installing, disassembling, and assembling each component are provided, along with essential precautions to ensure proper handling. **Maintenance Standards:** This section outlines judgment standards for inspecting disassembled parts, ensuring that components meet quality requirements and promoting consistent repair practices. **Others:** This section focuses on hydraulic and electric circuit diagrams, offering a visual representation of the system's flow and connections. Additionally, specifications for attachments and options may be included in this section. This manual is specifically designed for use in service workshops and provides technical information crucial for successful repairs and maintenance.

The Komatsu PC400-6, PC400LC-6, PC450-6, and PC450LC-6 are powerful and versatile hydraulic excavators manufactured by Komatsu, a renowned heavy equipment manufacturer. These models are designed for demanding construction, mining, and infrastructure projects, offering exceptional performance, durability, and efficiency. The PC400-6 and PC450-6 are standard models, while the PC400LC-6 and PC450LC-6 are long-reach versions, equipped with extended booms and arms for enhanced reach and versatility. All four models share common features, including a robust undercarriage with heavy-duty tracks, a spacious and comfortable operator cab with advanced controls, and a powerful diesel engine that provides ample power for demanding operations. The Komatsu PC400-6 and PC450-6 series boast a range of advanced technologies that contribute to their efficiency and operator comfort. The hydraulic systems are optimized for smooth and responsive operation, while the engine utilizes fuel-saving technologies to minimize fuel consumption. The spacious cab features ergonomic controls, a multi-function display, and an advanced climate control system to provide a comfortable and productive working environment for the operator. The excavators are also equipped with a comprehensive safety system, including a robust ROPS/FOPS certified cab structure and various safety features to ensure operator and equipment protection. These models are renowned for their reliability, durability, and ease of maintenance, making them a popular choice in industries where uptime is crucial.