by Jim Sutherland from Enviromotive
Beginning in 2007, things began to dramatically change with regard to heavy duty diesel engine maintenance. Starting that year, it was mandated that these motors have exhaust aftertreatment technology. This mandate dictated the inclusion of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF). In 2010, the EPA introduced additional requirements to eliminate NOx which led to a select catalytic reduction (SCR) system also being added to the after treatment system. To explain how this system works, we thought we would share this quote from John Lightner, Cummins Technical Sales Support Manager, from an article in Vehicle Service Pros. He stated, “What the DOC does is it changes the chemistry in the exhaust stream, and utilizes heat to burn the soot into ash, and the DPF stores the ash until it’s time to clean and have it removed. The SCR system, through a chemical reaction, by the introduction of the diesel exhaust fluid (DEF), changes the chemistry and eliminates the NOx and greenhouse gases, so that you have (a little water and nitrogen) coming out of the tailpipe. You’re not having the carbon dioxide coming out that gives you the greenhouse gas.”
With all of this added technology to these heavy duty diesel engines, it is important to understand how maintenance has changed. To eliminate problems with these systems, it is important that your motor is in top running condition. As Lightner says, “If your engine is not running correctly, then it’s going to emit more emissions and can plug up your filter and create more maintenance.” Having a motor that is not running efficiently will often lead to a mis-diagnosis of the underlying problem. The thought might be that a filter cleaning is all that is required. While the filter likely does need cleaned, if the motor is not properly operating, the filter will be clogged prematurely again. If you would like to read more on the importance of proper tuning, click HERE.
That being said, if the motor is running properly, what does proper aftertreatment system maintenance look like? The core part of any maintenance program will be the cleaning of the diesel particulate filter (DPF). This can be done by either replacing the filter or cleaning the filter. Replacing the filter can be done with either a new or a remanufactured unit. If you choose a remanufactured unit, ensure you are doing so from a reputable source as the history of these filters, and the way they have been cleaned, will have a large impact on how that filter will perform. You can also choose to have your specific filter cleaned. If you choose this route, it is important to understand that there are different cleaning methods. You will want to ensure that the filter is properly and thoroughly cleaned. To help you understand what the appropriate cleaning method for your circumstance might be, check out this article I wrote on the topic HERE.
Finally, I want to encourage you to not ignore proper maintenance of these systems. In an article in Vehicle Service Pros, Duane Bratvold, Western Regional Sales Manager for Webasto says, “Operator error is probably the number-one failure of a DPF. A lot of these guys will drive down the road and the light will come on and they don’t want to stop so they’ll just keep driving it until something goes wrong and they’re forced to pull over. If a light comes on you have to deal with it immediately.”
I hope that you found this article informative. If you have any questions about aftertreatment system maintenance or DPF cleaning strategies, please contact us today by calling 800-954-8265. We have the best informed DPF related technical support available in the industry.
You can also check out our EvacuBlast DPF Cleaning System by clicking HERE. Fill out the contact form below if you are interested in learning more. We look forward to hearing from you!