A Complete Guide to Buying a Used Doosan DH420LC-7 Excavator

The Doosan DH420LC-7 excavator, a large piece of machinery commonly used in construction, is highly regarded for its excellent performance and durability, making it a popular choice in the used equipment market. However, buying a second-hand excavator can be a complex decision-making process, especially for buyers without sufficient experience. This article provides a detailed guide to help you avoid common pitfalls and ensure that you select the best equipment when purchasing a used Doosan DH420LC-7 excavator.

1. Understand the Basic Features of the Doosan DH420LC-7 Excavator

Before purchasing a used Doosan DH420LC-7 excavator, it is important to understand its basic performance and features. This model is part of Doosan’s 7th generation hydraulic excavators and has the following notable features:

• Engine and Power System: The DH420LC-7 is equipped with a powerful engine, typically a diesel engine that offers high fuel efficiency.
• Hydraulic System: The hydraulic system is robust, providing stable digging power and smooth operational response.
• Cab Design: The cab is spacious and ergonomically designed, with an advanced control system that makes it easier for operators to work efficiently and with reduced fatigue.
• Durability: Doosan DH420LC-7 is built with a focus on structural integrity, especially for heavy-duty applications, offering excellent durability and resistance to wear and tear.

Having a clear understanding of these basic features will help you evaluate whether the equipment is suitable for your needs.

2. Determine Your Needs for Purchasing a Used Excavator

When buying a used 42ton Doosan DH420LC-7 excavator, it’s important to clarify the purpose and requirements of your purchase. Different working environments and project requirements call for different equipment configurations. Consider the following factors:

• Work Environment: If your project is located in muddy or uneven terrain, you may need a machine with better traction and stability.
• Usage Frequency: If you plan to use the excavator frequently, the maintenance history and condition of the equipment become even more critical.
• Budget: The price of a second-hand machine is influenced by factors such as age, hours of use, and maintenance history, so you need to select equipment that fits your budget.

3. Inspect the Equipment’s Condition

When selecting a used Doosan DH420LC-7 excavator, the operational condition of the equipment is paramount. Here are some key aspects to check:

Engine and Hydraulic System

• Engine Condition: The engine is the heart of the excavator, so it’s crucial to check its condition. Ensure the engine starts smoothly, listen for any unusual sounds, and check if exhaust emissions are clean. If possible, review the engine’s maintenance records.
• Hydraulic System: The hydraulic system directly affects the excavator’s efficiency and stability. Ensure there is enough hydraulic oil, check for leaks, and inspect the hydraulic pump, valves, and pipes for any signs of wear or damage.

Tracks and Undercarriage

• Track Wear: Check for cracks or excessive wear on the tracks, especially at turning and load-bearing areas. Track wear directly impacts the machine’s stability and operational efficiency.
• Undercarriage and Walking System: Inspect the walking mechanism for flexibility and check for any looseness or abnormal noise. The strength and stability of the undercarriage are crucial for ensuring smooth operation.

Electrical and Control Systems

Check if the control system and electrical components are functioning properly, including the instrument panel, joystick controls, and LED displays. Any issues with the electrical system can affect the machine’s operational efficiency.

Exterior and Structure

Inspect the exterior of the machine for any significant collision marks or corrosion. While wear and tear are expected on used equipment, excessive structural damage may indicate the machine has undergone heavy use.

4. Review the Equipment’s Maintenance History

Understanding the maintenance history of the used Doosan DH420LC-7 excavator is vital. Regular maintenance records can provide insight into the machine’s operating condition and whether it has undergone any major repairs. Request the following from the seller:

• Routine Maintenance Records: Ensure that routine tasks like oil changes, filter replacements, and hydraulic oil changes have been performed on time.
• Repair Records: Inquire about any major repairs, especially to the engine or hydraulic systems.

5. Communicate with the Seller

Establishing good communication with the seller is an essential step in purchasing a used excavator. Ask the seller about their reputation and sales history, and understand their after-sales service policy. Through direct communication, you can gain a better understanding of the machine’s actual condition. Additionally, request detailed photos and videos of the equipment to verify its status.

6. Price Evaluation and Market Research

The price of a used Doosan DH420LC-7 excavator varies based on factors such as age, usage, and geographic location. Conduct market research to understand the price range of similar models to help you assess the value for money of the equipment you are considering. Be cautious if the price is significantly low, as it could indicate hidden problems with the equipment.

7. On-Site Inspection and Test Run

It is highly recommended that you request an on-site inspection and test run of the equipment. During the test, you can personally evaluate the performance of the excavator, check for unusual sounds or vibrations, and ensure that the machine operates smoothly under working conditions.

8. Contract Signing and Payment

Once you have confirmed that the equipment meets your requirements and the price is reasonable, proceed to the transaction stage. Make sure to sign a formal sales contract with the seller, clearly outlining the machine’s condition, price, payment method, and after-sales service terms. Choose a secure payment method to ensure the safety of the transaction.

Conclusion

Buying a used Doosan DH420LC-7 excavator requires careful consideration and thorough inspection. This guide has provided you with a comprehensive overview of how to select, inspect, and purchase a used excavator to ensure you get the best value. Whether you are a first-time buyer or have some experience, meticulous inspection and adequate market research are key to securing reliable and durable equipment. We hope this guide helps you make an informed decision and successfully complete your purchase!