In 2008 Tier 4 engines were mandated for all new off-road construction vehicles. By 2015 they had largely met their goal of reducing harmful emissions from the diesel engines running generators, off-road construction equipment and heavy-duty trucks.
A combination of new technologies arms the cleaner performance of Tier 4 engines. Two parts present a particular challenge for maintenance: the “diesel particulate filter” and “diesel exhaust fluid.” They are DPF and DEF on your scorecard.
An engine’s exhaust system is where emissions and environment collide. DPF and DEF work together to keep more of the harmful pollutants from escaping than previous designs.
- The DPF traps soot and ash in the exhaust system. A truck making long hauls at highway speeds burns off the trapped particulates. In a generator that is powerful enough to run a large motor but mostly idles when it is run for test purposes, the gunk collected will not burn off as easily.
- DEF is a liquid combination of chemicals and water sprayed into the exhaust pipeline to help reduce a diesel engine’s pollutants output.
Common Tier 4 Engine Problems
1. Mistaking DEF for diesel fuel – if the mistake is caught immediately, the fuel system will need to be flushed and the engine evaluated for additional repairs. If, instead, the engine is started, it’s almost assured to require expensive repairs.
2. Mistaking diesel fuel as DEF – depending on the situation, repairs may range from removing the diesel and cleaning the DEF tank and replacing the DEF filter to more extensive work including replacing the tank, tank sender/DEF pickup, tank cap, DEF injector and NOX sensor “O2 sensor”
3. Running the engine on contaminated diesel fuel (water, particulates) – learn more about the risks of contaminated fuel and diesel fuel polishing
4. Allowing the diesel particulate filter (DPF) to become clogged – if an engine runs at a small load for too long, soot can build up to the point of a regen not successfully burning off the deposits. If dirty enough, the core can even get pushed out when trying to run a regen, requiring a replacement of the filter.
Tier 4 Maintenance
CD & Power has invested in the training and technology needed to service Tier 4 engines. In selecting us to maintain your engines, you gain the benefit of professional technicians, trained in the maintenance of these complex pieces of valuable equipment. Our pros carry with them something old, too: CD & Power’s accumulated experience of thirty-five years solving diesel engine problems.