This comprehensive manual provides in-depth information on the maintenance, assembly, disassembly, and servicing of Komatsu PC300-5, PC300LC-5, PC300LC-5K, PC300-5 MIGHTY, PC300LC-5 MIGHTY, PC300HD-5, PC400-5, PC400LC-5, PC400-5 MIGHTY, PC400LC-5 MIGHTY, and PC400HD-5 hydraulic excavators. It is specifically designed for machines with serial numbers starting from 21401 for PC300 models and 20603 for PC400 models. The manual is divided into two parts:

**Service Repair Manual:** This section delves into detailed specifications, diagrams, and real photo illustrations for complete step-by-step guidance on repair, diagnosis, servicing, technical maintenance, and troubleshooting procedures. The extensive information allows you to identify problems and understand how to repair and maintain your machine efficiently.

**Operation & Maintenance Manual:** This section focuses on safe and effective operation of your Komatsu excavator. It guides you through procedures for operation, handling, lubrication, maintenance, checking, and adjustment. The information helps ensure peak performance through effective, economical, and safe machine operation and maintenance.

The Service Repair Manual includes detailed sections on:

* **Safety:** A comprehensive introduction to safety procedures for working with the excavator.
* **Foreword:** Explanatory information about the manual's structure and content.
* **Structure and Function:** Understanding the design and operation of the machine's components.
* **Testing and Adjusting:** Procedures for verifying and adjusting various system settings.
* **Disassembly and Assembly:** Detailed instructions for taking apart and reassembling specific components.
* **Maintenance Standard:** Guidelines for maintaining the excavator according to factory specifications.

The Operation & Maintenance Manual includes sections on:

* **Foreword:** Explanatory information about the manual's structure and content.
* **Safety Information:** Essential safety precautions for operating and maintaining the excavator.
* **Introduction:** Overview of the excavator's intended use, features, and break-in procedures.
* **Location of Plates, Table to Enter Serial No. and Distributor:** Information on locating serial number plates and identifying distributors.
* **Contents:** A detailed table of contents outlining the manual's structure.
* **General Precautions:** Important safety guidelines to follow during operation and maintenance.
* **Precautions During Operation:** Specific safety measures for operating the excavator in various conditions.
* **Precautions for Maintenance:** Safety guidelines for performing maintenance procedures.
* **Position for Attaching Safety Labels:** Instructions on where to place safety labels for visibility.
* **General View:** A visual representation of the excavator's components and layout.
* **Explanation of Components:** Details about the purpose and function of each part of the excavator.
* **Operation:** Instructions on how to operate the excavator safely and effectively.
* **Transportation:** Information on safely transporting the excavator.
* **Cold Weather Operation:** Specific precautions for operating the excavator in cold temperatures.
* **Long-Term Storage:** Guidelines for storing the excavator for extended periods.
* **Troubleshooting:** Tips and methods for identifying and resolving common issues.
* **Guides to Maintenance:** A comprehensive overview of routine maintenance procedures.
* **Outlines of Service:** Information on specific service intervals and recommended work.
* **Wear Parts List:** A list of commonly replaced parts, including recommended replacement intervals.
* **Use of Fuel, Coolant and Lubricants According to Ambient Temperature:** Guidelines for using appropriate fluids based on operating conditions.
* **Standard Tightening Torques for Bolts and Nuts:** Recommended torque values for various fasteners.
* **Periodic Replacement of Safety Critical Parts:** Information on parts that require regular replacement for safety reasons.
* **Maintenance Schedule Chart:** A detailed chart outlining recommended maintenance intervals and procedures.
* **Service Procedure:** Step-by-step instructions for performing specific maintenance tasks.
* **Specifications:** Detailed technical specifications for the excavator.
* **Options, Attachments:** Information on optional equipment and attachments available for the excavator.
* **General Precautions:** Safety guidelines for handling attachments and optional equipment.
* **Handling Bucket With Hook:** Instructions for safely operating the bucket with a hook attachment.
* **Using Seat Belt:** Importance of wearing the seat belt during operation.
* **Handling Car Cooler:** Information on using a car cooler for operator comfort.
* **Handling Air Conditioner:** Instructions for using the air conditioning system.
* **Operation of Attachments:** Guidelines for operating various types of attachments.
* **Introduction of Attachments:** A description of common attachments available for the excavator.
* **Extending Machine Service Life:** Tips for maximizing the lifespan of the excavator.
* **Loading Shovel:** Specific instructions for using the excavator as a loading shovel.
* **General Locations:** Information on the location of key components and controls.
* **Instruments and Controls:** Explanations of the various gauges, switches, and controls.
* **Precautions for Machine Operation:** Important safety guidelines for operating the loading shovel attachment.
* **Maintenance:** Specific maintenance procedures for the loading shovel attachment.
* **Transportation:** Information on safely transporting the excavator with the loading shovel attached.
* **Specifications:** Detailed specifications for the loading shovel attachment.

The Komatsu PC300-5, PC300LC-5, PC300LC-5K, PC300-5 Mighty, PC300LC-5 Mighty, and PC300HD-5, along with their larger counterparts the PC400-5, PC400LC-5, PC400-5 Mighty, PC400LC-5 Mighty, and PC400HD-5, are a series of hydraulic excavators manufactured by Komatsu, a leading manufacturer of construction equipment. These excavators are renowned for their robust construction, high performance, and fuel efficiency, making them popular choices for various applications in the construction, mining, and quarrying industries. The PC300-5 series offers a range of options, each tailored to specific needs. The standard PC300-5 is a versatile machine suitable for general excavation and loading tasks. The PC300LC-5 features a long reach boom, ideal for working in confined spaces or reaching extended distances. The PC300LC-5K boasts a specialized boom for demolition work, offering increased power and durability. The Mighty versions of the PC300-5 and PC300LC-5 are equipped with enhanced hydraulic systems and reinforced components for heavier workloads and demanding conditions. The PC300HD-5, a high-density version, is designed for maximum productivity in deep excavations and challenging terrain. The PC400-5 series follows a similar pattern, with the standard PC400-5, long-reach PC400LC-5, Mighty versions for enhanced capacity, and the high-density PC400HD-5.

The Komatsu PC300-5 and PC400-5 series excavators feature a wide array of advanced technologies that contribute to their exceptional performance and operator comfort. The powerful Komatsu SAA6D107E-2 engine, known for its efficiency and low emissions, provides ample power for demanding tasks. The hydraulic system is designed for smooth and responsive operation, delivering precise control and optimal digging force. The cab offers a spacious and comfortable environment for the operator, with ergonomic controls, excellent visibility, and advanced safety features. These excavators also benefit from Komatsu's commitment to sustainability, with features like fuel-saving technologies and emissions reduction systems. The Komatsu PC300-5 and PC400-5 series continue to be highly sought-after machines in the construction industry, known for their reliability, performance, and operator comfort. Their versatility and adaptability make them valuable assets for a wide range of projects, contributing to the success of construction endeavors worldwide.