Engine builders prepare October emission changes

In an attempt to explain the changes fleet operators should anticipate in heavy diesel engines sold after October 1, 2002, the National Private Truck Council (NPTC) gathered representatives from the six engine manufacturers in North America. Each provided a description of the products being prepared to meet the deadline set by the consent decree imposed by the Environmental Protection Agency (EPA) on five of the manufacturers.

The discussion took place during the NPTC's 13th annual education management conference and exhibition held April 28-30, 2002, in Austin, Texas.

Detroit Diesel has four engine series ready for certification to meet the October 1, 2002, requirements, John Morelli, vice-president of on-highway engine programs for DDC, said. Those four are the DDC Series 50, Series 60, Mercedes-Benz MBE 4000, and Mercedes MBE 900. The Series 50 is a four-cylinder version of the six-cylinder Series 60. DDC has been producing the Series 50 with exhaust gas recirculation for two years and has 3,500 of the engines in service. In addition to the Series 60 engines, the two Mercedes-Benz engines comply with October 2002 standards, although they are not required to meet some of the emission standards until 2004, he said.

Using cooled exhaust gas recirculation, the Series 60 will meet the 2002 emission standards, Morelli said. A number of changes have been made to the engine so exhaust gas recirculation components can be added without increasing total engine weight. Performance has been enhanced as well with variable geometry turbocharging, he said. This provides control of engine boost pressure, allowing improvement in acceleration and engine braking performance. A high-output water pump provides the same amount of coolant flow through the engine as would have been available before the addition of an exhaust gas heat exchanger.

Increased cost, fuel use

Changes to the Series 60 are not free, Morelli said. Engines will cost more. In addition, fuel consumption will increase as a result of the new emission reduction components. Another change made necessary by the standards will be the use of oil newly formulated to meet the CI-4 standards of the American Petroleum Institute. Using those oils, fleet operators can maintain their preferred service intervals with changes extended as far as 30,000 to 35,000 miles.

Getting engines certified takes time, so not all horsepower ratings will be available immediately. The delayed ratings will be those at the lower end of the customer demand spectrum, Morelli said.

DDC shares the sentiments of many fleet operators about making expensive changes to equipment at a time when business already is suffering, Morelli said. Although DDC will have engines ready for sale, it agrees that fleets need more time for testing. The results projected by EPA may not materialize, he said, if fleets delay purchasing new engines or purchase used trucks instead.

Pollution reduction may be less than EPA desires, while the costs of placing these new engines in service could be higher than their estimates by a whole order of magnitude, Morelli said. EPA cost estimates are based on normal fleet buying behavior. If purchases remain at current low levels, the costs of engineering and producing these engines must be amortized over many fewer units. The increased cost could be as high as $10,000 per engine.

No EGR at Cat

Caterpillar has taken the position that it will not attempt to meet the October 2002 deadline using exhaust gas recirculation, said Gregg MacDonald, manager of on-highway engine products — national accounts division. In fact, Caterpillar will not have engines available in October that meet the EPA's standard for oxides of nitrogen (NOx) emissions. The company understands that it will have to pay a nonconformance penalty for taking this position, he said.

One of the reasons for this is the increased cost to fleets. If a fleet adds up all the additional costs resulting from purchasing engines placed on the market under EPA's short deadline, the total could be as high as $15,000 per engine. This total includes purchase price, resale value, operating costs, and increased fuel consumption, MacDonald said.

Fleet have several alternatives to purchasing new engines. They can accelerate purchases prior to October; they can postpone purchases by extending the service life of tractors already in service; or they can replace aging tractors by purchasing low-mileage used trucks, MacDonald said. For many fleets and some tractor manufacturers, buying used trucks could represent a benefit by driving up the value of used tractors. Whatever strategy fleets adopt to avoid purchasing new engines in October, the desired pollution reduction will not take place, he said.

Fleets avoiding new engines

Buying before the deadline or keeping existing trucks in service will result in no change for emission levels, MacDonald said. Purchasing used trucks could possibly put more vehicles on the road that use older engine technology, resulting in an emission increase. Early indications from truck builders suggest that fleets choose to buy early to avoid running engines that they believe to be tested inadequately. OEM records show orders currently at the same level as in 1999 or early 2000, obviously the result of prebuying.

Some large fleets have asked EPA to delay the new rules. Schneider National is a good example. It tests engines for two years before adopting new equipment, MacDonald said. Schneider is asking EPA for a delay that will provide the same emission reduction projected by making the standard effective in October. They suggest an extended test period followed by retrofitting existing engines to meet the standards so the final result achieves or beats EPA's projected reductions.

In October, Caterpillar will produce its 3126, C10, C12, and C15 engines. The C16 will not be in the product offering. In addition, all engine series will be offered with limited horsepower ratings, MacDonald said. Those ratings will cover nearly 98% of Cat's normal engine sales volume. The lower number of horsepower ratings is simply a tactic to buy time until Cat introduces its 2.5-gram compliant engines in 2003, when all ratings will again be available, he said.

Reduced emissions not to standard

Caterpillar engines after October will not be exactly like those on sale today; they will include improvements to reduce emissions. The more emissions can be cut, the lower a penalty the company will have to pay for noncompliance, MacDonald said.

In general, Caterpillar engines available after October 1, 2002, will be a great deal like current engines with many of the same components including the engine control module and turbocharger. However, the turbocharger will have an electronic waste gate instead of a mechanical waste gate, MacDonald said. Durability and reliability should remain the same as they are today. Maintenance intervals will not be affected, and fleets can continue to use CI-3 oils, if desired. Notwithstanding the few changes for October 2002, Cat engines will suffer a 2% to 3% fuel consumption increase this year, he said.

International is the only engine builder that was not required to sign the EPA consent decree. Part of that is because the company does not produce high-displacement engines for highway tractors, said James Marcoux, vice-president of sales and marketing of the engine group of International Truck and Engine. All International's engines are designed for medium trucks and buses.

International has a brand-new product, a V-8 engine called the VT-365 that was designed to meet the more-stringent 2004 emission standards in 2002, Marcoux said. The in-line six-cylinder engines — the DT-466, the DT-530, and the T-444E — will meet 2004 standards in January 2004. Because International was not required to sign the consent decree, its engines are not required to meet the same standards as those from the other manufacturers. International could have left its engines alone and simply introduced them when required in 2004, he said.

New engine platform

The VT-365, which has a horsepower range from 175 to 210, uses integrated exhaust gas recirculation and variable injection timing to meet the 2004 standards. Like its competitors, International uses variable geometry turbocharging in its new engine. The system is known as EVRT for electronic variable response turbocharging. The new engine actually has better performance and better fuel economy than the engine it replaces, Marcoux said.

The DT-466 and DT-530 engines will have a horsepower range from 195 up to 340. Recent changes in those engines have included a redesigned cylinder head that will allow use of four valves per cylinder instead of the two valves per cylinder in use today, Marcoux said.

International already is looking at changes to the engines for emission standards to come after 2004. Some of those changes will include a NOx-absorbing catalyst and an engine control module tailored to individual engine models, Marcoux said. As more electronics are required to sense engine performance and control operation, the electrical system must change to match. One possibility for change could be a 42-volt electrical system, up from today's 12-volt system.

Cummins certifies two engines

Cummins has two of its engine families certified to meet the 2002 emission standards, Michael Breeden, executive director of national accounts, said. The basic engineering solution to meet the October standards is an engine with cooled exhaust gas recirculation. In addition, Cummins uses a variable geometry turbocharger from Holset. More than 55,000 of those turbochargers have been in service in Europe since 1998. The company has 50 trucks in field tests and has logged 6.4 million miles with them in addition to 15,000 hours of test cell time. Most of this testing has been done with the ISX engine series, he said.

Cummins certified the ISX series early because it wanted to begin shipping engines to truck builders before October. The ISB engine series will be certified soon, and the paperwork to certify the ISC series is underway, Breeden said. Because the ISX is built on a new platform, the engine will have the same fuel economy after October that it has currently, and the ISB series will actually achieve better fuel economy than that produced by present engines, he said.

New Cummins engines will retain the extended oil drain intervals available from engines produced prior to October 2002. With the new CI-4 oils, the drain interval for the ISX series can easily be extended to 25,000 miles, Breeden said. Using cooled exhaust gas recirculation for emission control will have no impact on engine durability, so life-to-overhaul will be unchanged.

Get ready for new engines

Engines with exhaust gas recirculation are a fact, said Steve Ginter, vocational product manager for Mack. The oils for the new engines are ready; the engines are ready; and users need to get ready for the technology, he said. This technology is not as new as it might seem. Mack has been working on exhaust gas recirculation for five years. The big change in the product scheduling is that the EPA consent decree required the introduction to be moved forward by 15 months, Ginter said.

The 2002 emission standards are the fourth change in regulations since 1990. In each case, customers have expected their vendors to comply with the rules, and in each case they have, Ginter said. This compliance is not free. Meeting the 2002 standard will reduce fuel economy by about 2%. “We want better economy and are working to get better by October, but right now, 2% looks like the target figure,” he said.

Exhaust gas recirculation is wonderful for reducing emissions because it reduces combustion temperature. However, it does not add power to the engine, Ginter said. The key is to balance exhaust emissions against power. The Mack solution is to use a variable geometry turbocharger to force exhaust gas to mix with fresh intake air for use in combustion.

Mack seeks early customers

Mack is looking for customers to prove the worth of its engines, Ginter said. Before October 2002, the new engines will be available without any increase in price. After the October deadline, engine prices will increase by roughly $4,000, he said.

Mack recommends an oil change interval of 50,000 miles. That will not change after October; however, the engines will be required to use the new CI-4 oils. One reason that oil drain intervals can be 50,000 miles is a high-capacity oil system, Ginter said. Mack is adding eight quarts to its oil capacity in the new engine, bringing the total capacity up to 40 quarts — 10 gallons of oil. One result will be that mileage-to-overhaul will remain the same after October, he said.

Volvo uses cooled exhaust gas recirculation with variable pulse technology to control exhaust emissions, Jim Vance, a Volvo representative, said. Volvo does not use a variable geometry turbocharger. Lightweight components in the exhaust gas recirculation system in conjunction with other changes in the engines will allow Volvo to produce engines after October that weigh the same as current engines, he said.

The big change in Volvo engines is a double solenoid injector, which allows reshaping of the injection event, Vance said. Changing the injection reduces combustion temperature and lowers the amount of NOx created.

Using a fixed geometry turbocharger has implications for other parts of the engine, Vance said. For instance, Volvo will use a two-piece exhaust manifold in place of its previous one-piece manifold. Each segment of the manifold will serve three of the engine's six cylinders. Using a two-piece manifold will require two exhaust gas recirculation valves. Volvo's design moves exhaust gas through the EGR valve using the energy already in the exhaust stream by trapping the high-pressure release that occurs when exhaust valves in the cylinder head open following combustion. That momentary high pressure will force up to 30% of exhaust gas through the EGR valves into the recirculation chambers, he said.

The exhaust gas cooler is split into two sections as well, Vance said. That is one cooler segment for each part of the exhaust manifold. Coolant and exhaust gas will move through the heat exchanger in the same direction, extending the time of contact for optimum heat extraction from the gas. Engine coolant also will be used to cool the EGR valves, producing extended valve life.

With the change to CI-4 oils, maintenance intervals on Volvo engines will remain the same as they are today, Vance said. Engine oil capacity remains the same as present engines.

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