Hitachi Zaxis 20U Excavator: A Comprehensive Overview and Common Issues

[MikePhua]

The Hitachi Zaxis 20U Excavator is a compact yet powerful machine known for its impressive performance in tight spaces. Used widely in construction, landscaping, and utility work, this excavator has garnered attention for its fuel efficiency, operational ease, and durability. However, like any piece of heavy machinery, it is not without its challenges. This article delves into some of the common issues faced by owners and operators of the Zaxis 20U, along with maintenance tips and solutions to keep it in top working condition.
Overview of the Hitachi Zaxis 20U Excavator
The Zaxis 20U is a mini excavator that blends precision with power. Its compact size makes it ideal for projects in confined areas, such as urban construction sites or landscaping tasks, where larger machines might struggle. It offers excellent digging depth and reach, paired with a robust engine and advanced hydraulic systems, making it suitable for a wide variety of tasks.
Key features include:

• Powerful Engine: With a diesel engine designed for efficiency and power, the Zaxis 20U delivers solid performance.
  
• Compact Design: Ideal for narrow job sites or tight working conditions, it has a minimal turning radius and can operate in confined spaces.
  
• Advanced Hydraulics: The hydraulics system is designed to provide smooth, responsive operation, improving productivity on the job site.
  

While the Zaxis 20U is well-regarded in its class, some users have experienced specific issues that, if not addressed promptly, can affect performance.
Common Problems with Hitachi Zaxis 20U Excavator
Despite its strong reputation, some owners of the Hitachi Zaxis 20U excavator have noted a few recurring problems that can impact its functionality. These issues can often be resolved with proper maintenance or quick repairs, but it’s important to know what to look for.
1. Hydraulic System Issues
One of the most common problems faced by owners of the Zaxis 20U is related to the hydraulic system. The excavator’s hydraulic system is critical for powering the arm and boom functions. Common hydraulic-related problems include:

• Slow or Unresponsive Controls: This can happen due to air trapped in the hydraulic lines, insufficient hydraulic fluid, or pump malfunctions.
  
• Leaks: Hydraulic fluid leaks from seals, hoses, or valves can decrease system pressure, leading to loss of power and efficiency.
  

Solution: Regular checks of the hydraulic fluid levels and inspecting the system for leaks can prevent most issues. If slow or unresponsive controls are observed, it’s essential to bleed the hydraulic system to eliminate air or replace any worn-out components like seals or pumps.
2. Engine Performance Problems
Another issue that can plague the Zaxis 20U is engine performance. Common engine-related issues include:

• Difficulty Starting: This may occur due to battery problems, fuel issues, or a malfunctioning starter motor.
  
• Loss of Power: A common issue for excavators, often caused by clogged air filters, fuel injectors, or fuel lines.
  
• Excessive Smoke or Overheating: This is typically linked to coolant system malfunctions or clogged air filters.
  

Solution: Ensure that the fuel system is clean and free of blockages. Change the air and fuel filters regularly and check the battery to ensure it’s properly charged. If the engine is overheating, inspect the radiator and coolant levels, and replace any damaged components.
3. Track and Undercarriage Wear
Track wear is a typical issue for mini-excavators, including the Zaxis 20U. Tracks can suffer from wear and tear due to prolonged use, rough terrain, or improper tension.

• Uneven Track Wear: This can occur if the tracks are too loose or too tight, leading to unnecessary friction and damage.
  
• Damage to Rollers or Idlers: Prolonged use in harsh conditions can lead to the wear of rollers, sprockets, and idlers.
  

Solution: Regular inspection and adjustment of track tension are essential. Lubricating the undercarriage components and replacing worn-out rollers or tracks can prevent further damage and ensure smooth operation.
4. Electrical System Failures
Electrical issues are not uncommon in heavy machinery, and the Zaxis 20U is no exception. Problems with the electrical system can lead to operational delays, as the excavator relies heavily on electrical components for its control system, engine, and safety features.

• Malfunctioning Battery or Alternator: If the battery isn’t charging properly, it can lead to issues starting the machine.
  
• Faulty Wiring or Fuses: Loose connections or blown fuses can cause intermittent power loss or failure to start.
  

Solution: Regularly inspect the wiring for signs of wear, corrosion, or damage. Clean the battery terminals and check that the alternator is functioning correctly. Replacing faulty fuses and ensuring tight electrical connections can prevent many electrical issues.
Maintenance Tips for the Zaxis 20U
To prevent the above issues and keep your Hitachi Zaxis 20U excavator in good working condition, proper maintenance is key. Here are a few essential maintenance tips:

1. Regular Oil and Filter Changes
   Engine oil and hydraulic fluid changes should be done at regular intervals. Using the correct type of oil and changing it as recommended by the manufacturer can help prolong the engine’s life and ensure the hydraulics work efficiently.
   
2. Track and Undercarriage Care
   Inspect the undercarriage frequently for wear, and ensure that the tracks are correctly tensioned. Lubricate the rollers and idlers regularly to reduce friction and prevent wear.
   
3. Keep the Cooling System Clean
   Make sure the radiator and coolant system are free of debris to prevent overheating. Replace the coolant at the intervals specified by the manufacturer to maintain optimal engine temperatures.
   
4. Battery and Electrical Inspections
   Regularly check the battery’s charge and the condition of electrical wiring. Cleaning the terminals and replacing corroded wires will help ensure smooth electrical performance.
   
5. Preventive Inspections
   Implement a regular inspection routine for critical components like the hydraulic system, fuel system, and engine. This will help detect early signs of wear and prevent major breakdowns.
   

Conclusion: The Zaxis 20U’s Value in the Market
The Hitachi Zaxis 20U Excavator is a solid choice for those looking for a compact yet capable machine for tight job sites. Its reliability, fuel efficiency, and ease of operation make it an attractive option for contractors and businesses in need of versatile machinery.
While there are some common issues, such as hydraulic system problems, track wear, and electrical malfunctions, these can often be resolved through regular maintenance and prompt repairs. The Zaxis 20U, when well-maintained, provides excellent value for its class.
In the world of mini excavators, the Zaxis 20U stands out not just for its performance but also for its durability and low operating costs, making it a worthy investment for anyone in need of reliable compact excavation equipment.