The Pros & Cons of NewEmissions Technology Thetechnology applied to diesel engines is constantly changing and adapting tobecome a more ergonomic model of what came before. The changes can come becauseof problems encountered in previous models that was rethought of on how to doit to avoid said problem, or to help an engine conform to a standard applied bya state or country such as emissions. Emissions are the production anddischarge of gasses and radiation. This however can be a work in progress asengineers test out their solutions and as I’m coming to discover, this is truewith the emission systems applied in newer engines. Although it has its folliesit does have its redeeming factors as well.
Thesystem created was called the selective catalytic reduction (SCR) system. Itworks by injecting a liquid-reductant agent called diesel exhaust fluid (DEF)through a special catalyst into the exhaust stream of a diesel engine to reduceoxides of nitrogen (NOx) emissions. The pros that I have read upon are that itis one of the most cost-effective and fuel-efficient technologies available tohelp reduce diesel engine emissions.
Its effectiveness allows diesel engines tobe tuned and optimized toward maximum fuel efficiency, while the SCR system ishighly efficient at treating the engine-out exhaust. Thisis great for the environment, but not so great for engine life. The 70’s andthe 80’s left a bad taste in many mouths with no rules or regulations andemissions devices would rob power, made vehicles difficult and costly torepair, and ultimately led to the increased prices of vehicles. Back thenhowever was that they got great fuel mileage and were in service a very longtime. With today’s standards and regulations engines have been reeled back inand the engines and some who owned trucks with newer systems claim that thelifespan is affected by this process.
Althoughthe SCR system is a good step in the right direction there is always going tobe improvements and adaptations to the diesel engine to achieve the mostergonomic tractor available. Its our job as the mechanic to understand thesedevices and help make them function.