Top SCR Maintenance Tips for Heavy-Duty Trucks

Product | 08 Oct 2024

Maintaining the Selective Catalytic Reduction (SCR) system in heavy-duty trucks is crucial for both compliance with emission standards and overall vehicle performance. As regulatory bodies enforce stringent emission norms, truck operators need to ensure that their SCR systems operate efficiently. Neglecting SCR maintenance can lead to higher emissions, increased fuel consumption, and costly repairs, impacting the profitability of fleet operations. This guide outlines top SCR maintenance tips to help heavy-duty truck owners maximize system performance while extending vehicle life.

Understanding the SCR System:

Before diving into the maintenance tips, it’s important to understand how an SCR system works. The SCR system is an advanced technology designed to reduce nitrogen oxide (NOx) emissions from diesel engines. It works by injecting Diesel Exhaust Fluid (DEF) into the exhaust stream. The DEF, composed of urea and deionized water, breaks down harmful nitrogen oxides into nitrogen and water vapor, reducing harmful emissions and complying with government regulations.

Maintaining the SCR system requires careful attention. In this blog, we have listed some of the most effective ways to ensure your SCR system runs smoothly.

1. Use High-Quality DEF

The quality of Diesel Exhaust Fluid (DEF) is fundamental to the proper functioning of the SCR system. Poor-quality DEF can lead to crystallization in the injector, clogging the dozing valve and the spray nozzle, which can ultimately degrade the SCR system’s performance. Always use DEF that meets the ISO 22241 standard, ensuring it has the correct chemical composition to protect your SCR components from damage. Additionally, ensure that the DEF is free from contaminants, as impurities can impair system efficiency.

Fleetguard Filtrum offers Filtrum DEF, a premium DEF solution that ensures proper chemical composition and is rigorously tested in NABL-recognized labs. Using such high-quality DEF helps you avoid common issues like clogging and system degradation, thus safeguarding your investment.

 2. Regularly Inspect and Clean the DEF Tank

The DEF tank should be inspected regularly to ensure it remains clean and free of debris. Contaminants in the tank can enter the SCR system and cause clogging or corrosion, leading to expensive repairs. Ensure the tank cap is securely closed to prevent dirt, dust, or other particles from entering. It’s also essential to periodically clean the DEF tank following the manufacturer’s instructions, as even minor contaminants can disrupt the system’s balance.

Additionally, check the DEF levels frequently and refill only with high-quality DEF like Filtrum DEF to prevent the SCR system from running dry, which could cause the system to shut down or malfunction.

3. Monitor the SCR Catalyst Performance

The SCR catalyst is responsible for the chemical reaction that reduces NOx emissions. Over time, the catalyst can become clogged or contaminated, especially if poor-quality DEF is used. Regular checks on the catalyst's performance are essential to ensure the chemical conversion process remains effective. If your vehicle experiences higher NOx emissions or engine warning lights, these could be signs of a malfunctioning catalyst that needs attention.

Professional testing and monitoring tools can help assess the condition of the SCR catalyst. Scheduling routine maintenance with trained technicians will help keep the catalyst in optimal condition, preventing costly downtimes and potential fines for emission violations.

4. Check and Replace DEF Filters Regularly

The DEF filter is another key component of the SCR system that requires routine attention. DEF filters are designed to remove any impurities in the fluid before it enters the injection system. Over time, these filters can become clogged with contaminants, reducing their effectiveness and eventually leading to DEF pump failure or damage to the injector nozzle.

To avoid these complications, follow the manufacturer’s recommendations for replacing the DEF filters. High-quality DEF fluids like Filtrum DEF contain fewer impurities, thereby extending the life of the DEF filter and reducing the frequency of replacements.

5. Maintain Proper Storage and Manage DEF Stock Efficiently

Improper storage of DEF can lead to contamination and reduced effectiveness, negatively impacting the SCR system’s health. DEF is sensitive to temperature and sunlight exposure, which can degrade its quality and reduce its ability to lower NOx emissions. To avoid the risk of degradation and contamination, it’s essential to store DEF in a cool, dry place, in tightly sealed containers. However, instead of stockpiling large quantities, it’s more efficient to purchase DEF as needed. This not only prevents the blockage of space and capital but also ensures that you're using fresh, high-quality DEF.

6. Check the DEF Injector for Crystallization

Crystallization is a common issue that can affect the DEF injector if the fluid evaporates or DEF of substandard quality is used. Crystallization can block the injector, reducing the efficiency of DEF dosing and potentially damaging the entire SCR system. Regular inspections of the DEF injector are crucial for spotting early signs of crystallization. If you notice any build-up, it’s important to clean the injector or replace it as soon as possible.

Opting for high-quality DEF, such as Filtrum DEF, minimizes the risk of crystallization. Its formulation is designed to maintain optimal fluidity and performance, ensuring that your DEF injector operates without disruptions.

Conclusion

Maintaining the SCR system in heavy-duty trucks is not an option but a necessity for both meeting regulatory standards and ensuring the longevity of the vehicle. By following these tips given above, you can keep your SCR system running smoothly while avoiding costly repairs.

Fleetguard Filtrum offers world-class DEF solutions with its Filtrum DEF, ensuring that your SCR system receives the protection and care it needs. Formulated to meet ISO 22241 standards and rigorously tested for quality, Filtrum DEF helps truck operators avoid common SCR issues like clogging, crystallization, and system degradation. 

Choose Filtrum DEF for reliable and efficient performance while meeting stringent emission norms. Contact us to know more about ensuring the optimal performance of your SCR system.

Know more about Filtrum DEF: https://www.fleetguard-filtrum.com/solutions/products/filtrum-def