top

New Diesel Engines Need Answers

Challenges of the Trucking Industry

(Excerpt from Paul Whetstone, ICML Certified, with emphasis added.)

The Trucking Industry’s Challenge:

The people wanted cleaner air…the government enacted tougher regulations. In 1998, drastic cuts in emissions were imposed on the heavy duty Trucking Applications for bypass oil filtration systemshighway engines that manufacturers started scrambling with different technologies to meet the regulations. However, answers were hard to come by. The EPA filed suit and won the largest environmental settlement ever, estimated at over $1.1 billion dollars. Part of that settlement resulted in the EPA moving the 2004 target emission levels up to 2002. And it’s not over; the emission standards only get tougher in 2007 and 2010.

The only answer available from engine manufacturers to meet these accelerated standards was Exhaust Gas Recirculation (EGR) technology. Automobiles were subjected to these same types of regulations in the early 1970s. Most manufacturers went to catalytic converters and EGR valves. It eventually worked well on gasoline powered vehicles. But diesels are a different animal.

It was predicted back in 1998 that, because of EGR and ACERT technology, soot and water levels would rise and the oil would be stressed. No one knew exactly how bad it would be, but the results are coming in and it’s not looking good. Engines are gumming up with soot at 150,000 miles (250,000 kilometers), turbochargers are malfunctioning, rings and liners have to be replaced at about the same time and oil change intervals are falling quickly.

ECR Engines

EGR engines take a part of the exhaust, which is full of soot and burned fuel, cools it and puts it back into the engine. This is done using an EGR valve actuated at the turbocharger. Timing is also retarded at different speeds. All this alters the combustion process and lowers the amount of NOx, but it actually increases particulate matter (PM) or soot due to partial combustion. Some of this is trapped in exhaust filters, but most of the soot ends up in the engine oil. The engine oil, the life blood of the engine, has literally been turned into a trash dump. Engine temperatures rise, the cooling system is stressed, oil runs hotter and degrades faster and engine wear is accelerated. Oil drain intervals have been lowered from 40,000 kilometers to 15,000 kilometers in many instances to try to control the problem.

ACERT Engines

ACERT engines from CAT approach the problem in a different way, but they have issues also. ACERT uses advanced injector design, computer controlled injection and “lean burn” technology to lower NOx and keep soot levels down. To get this lean burn, two turbochargers are used in series to ram more air into the engine. Turbocharging puts large amounts of water into the oil, much like an air compressor, which has to be bled off water. However, the oil in an engine cannot be “bled”. Water in oil accelerates the formation of sulfuric acid and nitric acids which result in internal corrosion, pitting and wear of the engine.

A new oil formulation, API specification CI-4, was made to try to keep both soot and acids under control. These oils were formulated with much higher dispersancy additives and higher base numbers (TBN) to try to keep the extra soot in suspension and control acid build-up. While the specification is good, the results are tumbling due to increased soot levels and acid levels. Manufacturers are reversing their recommended oil change intervals downward to try to stop the accelerated wear.

An Effective Solution:

One extremely promising solution to the new challenges presented by the new engines is “Bypass Oil Filtration”. Bypass filtration takes oil out of the regular flow of the engine, where it is cleaned, then returned back to the oil reservoir. Referring back to our blood comparison, bypass filtration is similar to kidney dialysis for the engine. While full flow filters currently filter down to 30 microns at solid particle contaminants down to the 1 – 3 micron range.

Although an efficient Bypass filter improves the situation, there is still the issue of removing water (and other liquid contaminants) and the acid buildup that is caused. What is needed is a Bypass Oil filter system that not only filters solid contaminants but also allows for highly efficient liquid contaminant removal. An effective Bypass Oil filter system needs to remove water, and other liquids such as unspent fuel and antifreeze, on a continuous basis, not just absorbing them in the filter, which once saturated, will pass the liquids along.

Managing Your Fleet the Smart Way:

Extended drains or not, anyone operating the new engines without a proper oil analysis program in place is flying blind. The opportunity to extend oil drains only intensifies the need for regular oil analysis. Not having an oil analysis program is like being a doctor and not having access to a patient’s blood work. Without real-time data, you’re just guessing. Trucks are mobile, running in very different climates within a matter of hours. Temperature, altitude and humidity have great effects on the engines and different parts of the country have varying climates. In addition, engines can develop mechanical problems that prematurely end the useful life of a drain interval. Without timely oil information and analysis, establishing maximum drain intervals for an individual engine is just a shot in the dark.

It is also important to remember that in addition to giving you real-time feedback on your oil condition, a good oil analysis program allows you to do oil-based engine analysis. By evaluating engine wear metals and certain oil properties, early-stage engine problems can be detected and addressed before a critical breakdown occurs. And remember, metal (from the engine) is a lot more expensive to replace than oil. If your oil analysis program is not helping you regularly evaluate the condition of your engine then the power of that program is not being fully utilized.

Although increased government regulations have caused significant challenges to today’s trucking industry, there are answers. Bypass Oil filtration, in addition to an effective oil analysis program, is the best way to protect these expensive EGR engines and improve the economies of operating them. However, without effective blood work and preventative medicine, the patient may just continue to slide downhill.

, ,