Replacing Return Line Seals on the International Dresser TD20 Dozer (DVT573 Engine)

[MikePhua]

The International Dresser TD20 dozer, equipped with the DVT573 diesel engine, is a robust machine known for its durability in heavy-duty applications. However, like all machinery, it requires maintenance to ensure optimal performance. One common maintenance task is replacing the return line seals, which are crucial for maintaining the integrity of the fuel system.

Understanding the Role of Return Line Seals
Return line seals are integral components in the fuel system of diesel engines. They prevent fuel leaks at the injector return lines, ensuring that excess fuel is safely returned to the fuel tank without contaminating other engine components. In the case of the DVT573 engine, these seals are located at the injector return lines and are subject to high pressure and temperature conditions.

Identifying the Correct Seal Dimensions
Accurate identification of the seal dimensions is essential for a successful replacement. For the DVT573 engine, the return line seals typically have the following approximate dimensions:

• Height: 0.270 inches
  
• Outer Diameter (OD): 0.475 inches
  
• Inner Diameter (ID): 0.250 inches (seals to a 0.250-inch OD return line)
  

These dimensions are based on user reports and may vary slightly depending on the specific model and manufacturing tolerances. It's advisable to measure the existing seals before purchasing replacements to ensure compatibility.

Sourcing Replacement Seals
Finding the correct replacement seals can be challenging due to the age and specificity of the DVT573 engine. However, several avenues can be explored:

• Komatsu Dealers: Since Komatsu acquired Dresser, they may have compatible parts or can provide guidance on sourcing the correct seals.
  
• Aftermarket Suppliers: Companies like CEA-Services offer seal kits compatible with Dresser TD20 models, which may include the necessary return line seals.
  
• Online Marketplaces: Platforms like eBay and TractorPartsASAP list various seal kits and individual seals that may fit the TD20 dozer.
  

It's crucial to verify the compatibility of any replacement seals with the DVT573 engine before purchasing.

Installation Process
Replacing the return line seals involves several steps:

1. Preparation: Ensure the engine is cool and disconnect the battery to prevent any electrical hazards.
   
2. Accessing the Injectors: Remove any components obstructing access to the fuel injectors, such as air intake hoses or engine covers.
   
3. Removing Old Seals: Carefully detach the return lines from the injectors. Use a seal removal tool to extract the old seals without damaging the injector ports.
   
4. Cleaning: Thoroughly clean the injector ports and return lines to remove any debris or old seal remnants.
   
5. Installing New Seals: Lubricate the new seals with clean diesel fuel and install them into the injector ports. Ensure they are seated properly to prevent leaks.
   
6. Reassembling: Reconnect the return lines to the injectors and reassemble any components removed during the process.
   
7. Testing: Start the engine and check for any fuel leaks around the injector return lines. If leaks are present, recheck the seal installation and ensure proper seating.
   

Maintenance Tips
To prolong the life of the return line seals and ensure the longevity of the fuel system:

• Regular Inspections: Periodically check for signs of fuel leaks around the injector return lines.
  
• Use Quality Fuel: Ensure the use of clean, high-quality diesel fuel to prevent contamination and clogging of the return lines.
  
• Proper Storage: If the dozer is not in use for extended periods, store it in a dry environment to prevent corrosion of fuel system components.
  

Conclusion
Replacing the return line seals on the International Dresser TD20 dozer with the DVT573 engine is a manageable task that can prevent costly repairs and downtime. By sourcing the correct seals, following proper installation procedures, and adhering to maintenance best practices, operators can ensure the continued reliability and performance of their equipment.