AdBlue, also known as Diesel Exhaust Fluid (DEF), is a critical component in modern diesel engines for reducing harmful emissions. However, if the AdBlue tank becomes contaminated with dirt, incorrect fluid, or water, it can cause significant issues with the Selective Catalytic Reduction (SCR) system, leading to engine performance problems and potential damage. Flushing the AdBlue tank is essential when contamination occurs. This article provides a step-by-step guide on how to flush the AdBlue tank on both Doosan and Hitachi excavators.
Tools and Materials Needed:
- Clean water (preferably deionized or distilled)
- Replacement AdBlue fluid
- Wrenches and screwdrivers (appropriate sizes)
- Clean cloths or rags
- Safety gloves
- Safety goggles
- A clean container for draining the contaminated AdBlue
- A funnel (optional)
Step-by-Step Guide
1. Safety Precautions
- Turn Off the Excavator: Park the excavator on a stable, level surface. Ensure the engine is turned off and the key is removed from the ignition.
- Disconnect the Battery: To avoid any electrical issues or accidental startups, disconnect the battery terminals. Start with the negative terminal, then the positive terminal.
2. Locate the AdBlue Tank
- The AdBlue tank is usually located near the fuel tank on both Doosan and Hitachi excavators. Refer to your machine’s manual for the exact location if you’re unsure.
3. Drain the Contaminated AdBlue
- Position a Container: Place a clean container under the drain valve or the lowest point of the AdBlue tank to catch the contaminated fluid.
- Open the Drain Valve: Carefully open the drain valve or remove the drain plug using the appropriate wrench. Allow the contaminated AdBlue to fully drain into the container. Be patient, as this may take several minutes depending on the tank’s size.
- Dispose of Contaminated Fluid: Dispose of the contaminated AdBlue according to local environmental regulations. Do not reuse or attempt to filter it, as contamination can severely affect the SCR system.
4. Flush the AdBlue Tank
- Rinse the Tank with Water: Once the tank is empty, flush it with clean water to remove any remaining residues. Use deionized or distilled water if possible to prevent further contamination.
- Shake and Drain: If the tank is removable, you can gently shake it to ensure thorough rinsing. Drain the water completely using the drain valve or plug.
- Repeat if Necessary: If you suspect any residual contamination, repeat the flushing process until the water draining out is clear and free of any particles.
5. Inspect and Clean Components
- Check the Tank: Visually inspect the interior of the tank for any remaining debris or contamination. Use a clean cloth to wipe down the inside if necessary.
- Clean the Fill Neck and Cap: Ensure the fill neck and cap are clean before refilling. Contaminants can easily enter the tank during refilling if these components are not cleaned.
6. Refill the AdBlue Tank
- Use Fresh AdBlue: Only refill the tank with fresh, uncontaminated AdBlue fluid. Ensure the fluid meets ISO 22241 standards, which is the industry standard for AdBlue quality.
- Avoid Spills: Use a funnel to prevent spills and overfilling. Carefully pour the AdBlue into the tank until it reaches the appropriate level.
7. Reconnect the Battery
- Reconnect the Battery Terminals: Once the tank is refilled, reconnect the battery terminals, starting with the positive terminal followed by the negative terminal.
8. Start and Test the Excavator
- Power Up the Machine: Start the excavator and allow it to run for a few minutes. Monitor the dashboard for any warning lights or error codes related to the AdBlue or SCR system.
- Check for Leaks: Inspect the area around the AdBlue tank and drain valve for any leaks. Ensure that all connections and plugs are properly secured.
9. Monitor AdBlue System Performance
- Watch for Warnings: Over the next few operating hours, keep an eye on the AdBlue system for any abnormalities, such as reduced engine power or new warning lights. This will help ensure that the flushing process was successful and that no further contamination remains.
10. Dispose of Waste Properly
- Environmental Considerations: Dispose of the contaminated AdBlue and any cleaning materials in accordance with local environmental regulations. Do not dump contaminated AdBlue or rinse water into the environment or standard drainage systems.
Conclusion
Flushing the AdBlue tank on Doosan and Hitachi excavators is a necessary procedure when contamination occurs. Properly maintaining the AdBlue system ensures the longevity of the SCR components and keeps your excavator running efficiently while complying with emission standards. By following these steps, you can effectively flush the tank, replace the contaminated fluid, and restore your machine to optimal working condition. Always refer to the excavator’s manual for specific instructions and recommended procedures for your model.
If you have further Adblue related problems, we can supply you with an Adblue emulator for the Doosan / Hitachi machine that will fix the Adblue problem. Contact us for further info as we can help you.
