Maintenance of Interim Tier 4 Engines

The implementation of Interim Tier 4 diesel engine emission regulations will bring new high-horsepower engines to the farm. And while there are one of two emission compliance technologies being used by engine manufacturers that producers will have to choose from, there is some good news with this new technology: oil change intervals have expanded, and oils needed for these new engines are backward compatible with other engines.

First, it’s important to understand the two technologies being used by each engine manufacturer.

Both technologies are used to achieve the same end result: a cleaner burning diesel engine with reduced emissions, and two new acronyms: EGR and SCR.

EGR

Exhaust Gas Recirculation (EGR) diverts a percentage of the exhaust gas back into the cylinder, lowering combustion temperatures and thereby reducing NOx. A diesel particulate filter (DPF) in the exhaust system traps and holds the remaining particulate matter (PM), which are then oxidized in a process called regeneration.

SCR

Selective Catalytic Reduction is an after-treatment technology that uses a chemical reductant, Diesel Exhaust Fluid (DEF), also known as urea (a solution containing 32.5 percent urea plus deionized water), which is injected into the exhaust stream where it transforms into ammonia and reacts with NOx on a catalyst, converting the NOx to harmless nitrogen gas, small amounts of CO2 and water vapor.

We’ve talked to the major engine manufacturers on the technology each is using, and have identified new maintenance issues.

Case IH

Case IH is using SCR technology for medium- and heavy-duty engines (greater than 100 hp) and cooled EGR for light-duty engines (less than 100 hp). Engine performance is improved because SCR reduces emissions in the exhaust stream, allowing the engine to be tuned for performance and fuel efficiency. The company says it is seeing a minimum 10 percent average operating cost improvement over the company’s Tier 3 engines.

SCR requires the addition of DEF, commonly used in new farm pickups and on-highway grain trucks and is currently priced about the same as diesel fuel used at a rate of 3 percent to 5 percent of diesel fuel. Taking DEF use into account the company says an average 10 percent reduction in operating costs are realized over previous models as a result of fuel savings and reduced oil changes. DEF requires no special handling.

The oil drain intervals are now expanded to 600 hours on all Interim Tier 4 engines with SCR, and there are no special oil filters required. Case IH engineers have changed oil filters on various models because of engine and chassis changes on various new models. Most of the Interim Tier 4 engines have gone to a cartridge style filter.

The Case IH Tier 4i SCR engines continue to use 15W 40 in either a CI-4 which was used in the past or they can use the new CJ-4. Since Tier 4 EGR/DPF engines require CJ-4 rated oil, the trend is to use CJ-4 so only one oil is needed on the farm.

Compared to a Tier 3 tractor the only other maintained item is DEF filters, which may last up to 3,600 hours, to take care of any contamination that may have entered from the filler neck.

AGCO

AGCO is using SCR (e3) on high-horsepower tractors (Challenger MT600C and MT600D; AGCO DT, Massey Ferguson 8600 and Valtra S Series, Gleaner Super Series combines, Select TerraGator and RoGator models and other products coming very soon.) Fendt 800 and 900 Series tractors also employ SCR technology to meet emissions compliance requirements.

The company says e3 technology alone achieves NOx reductions in excess of 90 percent.

E3 technology delivers uncompromised horsepower and torque from a cooler running engine, and delivers up to 20.8 percent in fuel savings compared with competitive models, AGCO says. Service and maintenance needs of the engine are unaffected. Maintenance of the e3 SCR system is minimal. The DEF tank is refilled approximately every other diesel fill. The diesel exhaust fluid filter must be changed every two years or 4,200 hours.

DEF is consumed at a rate of approximately 3 percent of the fuel used for Tier 3 products and 5 – 7 percent for Tier 4 interim products. Therefore, for every 100 gallons of fuel used, 3 gallons of DEF/AdBlue will be consumed. DEF can be purchased at any AGCO/MF/Challenger dealership or through a variety of suppliers such as Brenntag in North America. Most truck re-fueling locations are stocking DEF with more than 3,800 locations reporting availability (source: discoverdef.com). The storage system and filling systems must be designed to assure a temperature range of between 12 degrees and 176 degrees F. DEF ranges from approximately $2.50 per gallon to $3.70 per gallon depending on source and volume purchased. DEF is the only additional fluid required for Interim Tier 4 tractors beyond those normally required in diesel engines.

The oil drain interval on Interim Tier 4 engines is every 400 hours, maximum; as often as every 200 hours in heavy working conditions. The oil change interval in these engines is actually longer than previously available engines of the same horsepower. Oil filters have not changed from previous models. This simplifies inventory and supply management for both dealers and tractor owners.

The engine oil specification is CJ-4. The weight is based on ambient temperatures in which the equipment is being operated, which is no different than previous engines.

The engine’s need of service and maintenance is unaffected by e3 technology. The maintenance of the e3 SCR system is at a minimum. The DEF tank is refilled approximately every other diesel fill. The main paper diesel exhaust fluid (DEF) filter is required to be changed every 4,200 hours or at 2-year intervals.

Cummins

Cummins will meet the 2011 emissions standards for engines in the 174- to 751-hp band with an integrated Cummins Particulate Filter exhaust after treatment and a cooled EGR system.

A Cummins Particulate Filter in combination with cooled EGR will achieve the best operating value for customers with up to 5 percent better fuel efficiency and no need for DEF.

Cummins Interim Tier 4 engines have demonstrated up to 5 percent improved fuel efficiency compared to Tier 3, depending on rating and duty cycle. Cummins VGT Turbocharger, which combines the benefit of both a small and large turbocharger in a small unit, enhances Interim Tier 4 equipment productivity with faster engine response, the company says.

An infrequent service will be ash cleaning of the Cummins Particulate Filter. The EPA has set a minimum interval for cleaning the filter at 4,500 hours for above 173 horsepower. Cummins expect the filter to reach 5,000 hours before ash cleaning is required. The crankcase filter requires a simple filter element change at 2,000-hour intervals.

Overall operating costs for Cummins engines will be lower at Interim Tier 4 compared with Tier 3. The company claims up to 5 percent better fuel efficiency can be achieved without the cost of DEF. This will more than offset the marginal cost increase associated with using ultra-low sulfur diesel (ULSD) fuel, low ash lube oil and particulate filter cleaning at 5,000 hours.

Cummins Oil drain intervals for Interim Tier 4 are the same as the Tier 3 products, use the same type of oil filters and are approximately the same price.

The EPA requires the use of low ash oil as part of the requirements to meet Interim Tier 4. This low ash oil is usually the same price, if not a little more than other types of oil. CJ-4 is the American Petroleum Institute (API) lube oil specification for engines using exhaust aftertreatment such as a Diesel Particulate Filter (DPF) and cooled Exhaust Gas Recirculation (EGR). Commonly known as “low ash” oil, it is more resistant to heat and leaves lower amounts of ash deposits when it does burn off during the combustion process. The lower ash content of the oil enables the DPF to reach the EPA mandated 4,500 hour ash cleaning service interval for engines above 174 hp (130 kW). However, Cummins expects to extend this service interval to 5,000 hours.

The new CJ-4 is backwards compatible so it can also be used in engines meeting Tier 3/Stage IIIA and other previous emissions regulation standards as long as the engine is also operating ULSD fuel (15 ppm or less sulfur content).

To be complaint with Tier 4 legislation, Cummins incorporated a crankcase filter and an aftertreatment system. These required components have maintenance intervals aligned with other major maintenance intervals on the current product.

Any additional maintenance required for Interim Tier 4 products will be more than offset by fuel efficiency improvements of up to 5% from a total cost of ownership standpoint, dependent on rating and duty cycle.

John Deere

John Deere Power Systems will use the company’s Tier 3 PowerTech Plus engine platform with cooled EGR and add an exhaust filter, replacing the muffler, to achieve compliance with IT4 (Interim Tier 4) regulations for the 174 horsepower and above product line.

Cooled EGR, combined with an exhaust filter, is the right choice because it is simpler for the operator, field proven and fuel efficient, the company says.

John Deere says that with the company’s Tier 3 PowerTech Plus engines, John Deere Power Systems achieved best-in-class fuel economy over Tier 2 engines while maintaining or improving cold-weather starting, transient response time, power bulge, peak torque, and low-speed torque.

The oil change interval will be the same or greater than that for Tier 3 engines, up to 500 hours, depending on the application. Regulations require minimum exhaust filter service intervals of 4,500 hours for engines 174 horsepower and greater and 3,000 hours for less than 174 horsepower. The John Deere exhaust filter design allows for greater service intervals to maximize uptime.

Oil drain intervals are 500 hours maximum (must use less than 15 ppm sulfur fuel, John Deere filters and Plus 50 II oil). Oil used is SAE CJ-4 specification (low ash) John Deere Plus 50 II. This oil can be used in Tier 3 and previous engines. When using this oil, change interval goes to 500 hours maximum as long as use is less than 15 ppm sulfur fuel.

MTU

The company supplies Mercedes engines to Claas, Krone, Miller Sprayers and Oxbo. It will have SCR for engines under 750 horsepower.

SCR requires no internal engine changes, since it treats the exhaust after the combustion event. Advantages include increased engine performance, better fuel economy, longer oil change intervals and no requirement for ultra-low-sulfur diesel fuel.

The increased NOx production is neutralized by the SCR after treatment. The company says it is finding a 5 percent increase in fuel economy, which is offset by 2 percent with the need for DEF. This results in a net fluid decrease of 3 percent over current Tier 3.

Maintenance intervals are unchanged from Tier 3. The Tier 4 engine allows for longer oil change intervals compared to EGR because inert exhaust is not being recirculated back into the combustion chamber, the company says. The only additional operating cost is the cost of DEF, which is used at a rate of approximately 1 gallon to every 25 gallons of diesel fuel and is currently priced about the same as diesel fuel. MTU says that the DEF cost is more than offset by improved fuel economy over EGR/DPF. The company says not requiring a DPF offers the benefits of no active of passive regeneration and no cleaning expense of the DPF.

Oil drain intervals will vary by engine series and loading factors, but will have similar drain intervals as Tier 3 engines. Each engine series uses its own unique oil filters, and they are the same from Tier 3 to Interim Tier 4. The oil used may be compatible with older engines, but it is best to check the requirements of the older engines in use to verify.

There are no special requirements for changing or servicing oil on Interim Tier 4 engines.

New Holland

The company will use SCR for machines with engines above 100 horsepower and cooled EGR for engines below 100 horsepower.

SCR technology does not place any additional demands on the cooling package, which means that no power is diverted to cool the exhaust gas. The engine’s power is only used for the machine’s principal working functions, improving productivity and significantly increasing the Engine Power Management band. Engines benefit from significantly better fuel economy, plus more power and torque.

The addition of AdBlue/DEF contributes to significant fuel cost savings, even when the initial purchase price is taken into account. The New Holland dealer network will sell the AdBlue/DEF in a variety of container sizes.

Oil drain intervals for Interim Tier 4 engines are 600 hours, and while there are different part numbers the filtration level is the same. Oil used is compatible with other engines on the farm. Refill of the DEF tank is done every second fuel fill up.
Cat
Cat Industrial engines will use a cooled exhaust gas NOx reduction system and particulate after treatment to achieve Tier 4 Interim/Stage IIIB emission requirements.

More powerful engine electronics, next-generation fuel systems, the Cat NOx Reduction System (NRS) Cat Clean Emission Module (CEM) are the ACERT Technology building blocks that result in reliable, durable engines, the company says.

Cat Tier 4 Interim/Stage IIIB technology engines produce up to 5 percent improved fuel efficiency compared to Tier 3/Stage IIIA, depending on applications, rating and operating conditions, the company says.

Oil and filter change service intervals of 250 or 500 hours remain the same as those for Tier 3/Stage IIIA engines. The Cat DPF is designed for 5,000 hours before ash cleaning is necessary. The Clean Emissions Module is designed with a removable center section to allow easy access to the DPF for ash service.

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