Truck Parts and Service | Heavy Duty Trucking, Aftermarket, Service Info
Issue link: http://read.dmtmag.com/i/700851
24 Service Bay PEAK Commercial and Industrial. Failed sensors do the same. Cummins says its SCR systems recog- nize solutions other than DEF and when polluted trigger a cab indicator light to inform drivers. Unfortunately dust or microscopic particulate contamination can take longer to be identifi ed. "It's all about maintaining a closed system," Schaeffer says. "You don't know you have a problem until something shows up in the engine." Dunnuck says Cummins' aftertreat- ment system also has built-in fi lters be- tween the DEF tank and SCR system but says the safest way to avoid contamina- tion remains in the hands of vehicle op- erators. Because DEF is typically added during fueling stops — and used at a rate of 2 percent compared to diesel fuel — Dunnuck says Cummins advises all driv- ers to take the same anti-contamination precautions they do when refueling. Additional cleaning intervals, either during preventive maintenance stops or independently, also are recommended. "We have a lot of products in very dusty environments where the [contami- nation] risk is high," says Dunnuck. "If you get enough debris in there over time, it can clog up a [DEF] fi lter just like it would a fuel system." This is an area where aftermarket ser- vice providers can capitalize. Adding DEF tank and aftertreatment system cleaning into PM stops takes just minutes, and provides customers unfamiliar with the technology valuable piece of mind. DEF management Because it's more than two-thirds water, Cummins says DEF does carry a minor risk of evaporation or freezing in ex- treme temperatures, particularly when in bulk storage containers. Dunnuck says the company recommends storing DEF at 77˚F and out of direct sunlight. Testing has determined the fl uid has a shelf life of more than six months when stored in extreme heat (95˚F). It also has a freeze point of 12˚F. Cummins says when the fl uid's formula is compromised it should be discarded. "If the urea concentration does become more or less than recom- mended over time, the DEF tank should be drained," the company says. DEF also poses minor risks outside of a tank. Though the fl uid is nontoxic, nonpol- luting, nonhazardous and non-fl amma- ble, the urea portion is corrosive to cop- per, brass and other materials. Cummins recommends any washing or rinsing any corrosive surfaces that come in contact with DEF — including truck bodies and fl oor drains — to minimize these risks. Dunnuck says Cummins uses corrosion-resistant materials such as high density polyethylene (HDPE) for its DEF tanks and hoses, and recommends all bulk distributors and end users do the same. A common sense approach can go a long way, Schaeffer says. "You can't totally ignore [DEF] but it's not something vehicle operators should have to worry about," he says. "It's a pretty simple system and it works quite well." T R U C K P A R T S & S E R V I C E | J u l y 2 0 1 6 Diesel exhaust fl uid producers advise against consumers attempting to mix their own fl uid. Improperly formulated DEF reduces SCR system productivity and increases system failures. Diesel exhaust fl uid is available at most fueling stations and is used at a rate of 2 percent compared to diesel fuel.