Tier 4 diesel engine emissions rules are currently the most stringent EPA emissions requirements for off-highway diesel engines. This regulation limits the quantity of particulate matter (PM), often known as black soot, and nitrogen oxides (NOx) that an off-highway diesel engine can generate.
Tier 4 criteria were phased in beginning in 2008, based on an engine’s horsepower rating. PM and NOx emissions had been lowered by 99 percent compared to 1996 levels by the time the final Tier 4 standards were fully implemented in 2015.
What does a Tier 4 engine mean?
A Tier 4 engine is one that meets EPA regulations and can be found in forklifts and other heavy machinery such as tractors and excavators. Tier 4 was created to reduce pollutants and bring off-highway vehicles up to the same environmental standards as highway trucks and buses.
What is the difference between Tier 3 and Tier 4 engines?
Since 2000, the United States’ Environmental Protection Agency (EPA) has required diesel engine manufacturers to minimize exhaust emissions on new engines designed for off-road use in the United States.
The EPA Tier 4i (Interim) emissions rules were in effect until the end of 2012, when they were replaced by the Tier 4 Final. According to the EPA, any diesel engine developed after January 1, 2013 for use in an off-road product sold in the United States must comply with the stricter EPA Tier 4 Final compliance rules. The EPA has made provisions for some leeway in completing the changeover.
The major addition of Diesel Exhaust Fluid to the exhaust system was a contentious necessity (DEF). It’s a combination of pure water and urea. A chemical reaction occurs when it is injected into the exhaust, turning the exhaust to nitrogen and water vapor. For the DEF system to work, the engine system must be hot enough to totally burn the gasoline. Diesel particulates build in an exhaust filter if the engine isn’t running hot enough, producing back pressure.
Tier 4 engines must be used in the construction of new pump stations. Existing applications, on the other hand, can continue to use Tier 3 engines that meet certain criteria. There are numerous benefits to refurbishing existing Tier 3 engines rather than replacing them with new Tier 4 engines, according to MWI Pumps expert Joe Hathcock.
Here are seven reasons why rebuilding a Tier 3 engine is preferable to purchasing a new Tier 4 engine.
- Engines of Tier 4 are more expensive. When comparing the cost of purchasing a Tier 4 engine to the cost of rebuilding a Tier 3 engine, the cost of purchasing a Tier 4 engine is around 60% more. Many other components are also necessary, such as DEF fuel and a particle filter that, if blocked, can cause the engine to shut down.
- A pump station modification may be required as part of a Tier 4 upgrade. The larger Tier 4 engines will almost always necessitate a larger platform, which adds to the upgrade time and cost.
- DEF fluid is not required for Tier 3 engines. DEF (also known as AUS 32 and marketed as AdBlue) is a liquid that is used to reduce the amount of pollution produced by diesel engines. To achieve Tier 4 final emission criteria, equipment manufacturers use selective catalytic reduction (SCR). By breaking down particulate matter and nitrogen oxide, this technique injects DEF into the diesel engine exhaust system to achieve the desired emission reduction.
DEF is nontoxic, nonpolluting, nonflammable, nonhazardous, stable, and colorless, which is great news. The disadvantage is that DEF is corrosive to most metals and coatings because it is nitrogen-based. DEF is also more vulnerable to contamination than other fluids.
There are no DPF filters on Tier 3 engines. DPF (diesel particulate filter) is a technology that uses high-tech filtering and regeneration processes to eliminate the majority of solid carbon-based emissions from exhaust. These Tier 4 filters can become clogged and require removal in order to be cleaned, resulting in additional costs and downtime.
There are fewer sensors in Tier 3 engines, thus they are less likely to malfunction or break. A sophisticated engine control system is one of the primary components necessary to satisfy Tier 4 regulations. The engine control unit (ECU) houses this control system, which controls dozens of operating and environmental factors in order to optimize horsepower, torque, and load responses. It enables the engine to retain combustion efficiency throughout a wide range of operating situations while reducing exhaust pollutants. This control system communicates all engine characteristics, including pressure, temperature, regeneration requirements, and engine failures.
However, according to Hathcock, having these sensors has more drawbacks than benefits. The Tier 4 engine sensors tell the engine when it’s time to regen, or clean itself. The sensors must all be working when the diesel exhaust sprays into the engine and burns off. If one of them fails, the system enters “limp mode,” which means it can only perform at 20% of its normal capacity, he noted. When this occurs, the regen must be manually forced. This can result in a large amount of downtime. Tier 3 engines do not have these sensors because they do not use a DPF and so do not require them because they do not burn anything.
The regen procedure for Tier 4 engines may necessitate downtime. Regen is an expensive self-cleaning process for the system and exhaust filter. To burn off the DEF liquid and send it out the exhaust, the temperature must be at a specified level.
Tier 3 engines are capable of handling a broader variety of loads. A Tier 3 engine can run at high speeds or idle for hours. A Tier 4 engine must maintain a high rpm—generally at least 1600 rpm—even if this is not the most efficient speed for every application. The Tier 3 engine’s ability to run efficiently at a variety of speeds, according to Hathcock, is an advantage.
According to Hathcock, repairing a Tier 3 engine is not difficult. It will need to be taken out of service, stripped down, properly cleaned, and rebuilt with new parts. Hathcock proposes using replacement parts from the original equipment manufacturer and claims that the process can be completed in a matter of weeks. Liners, pistons, cooling injection pumps, and other parts may need to be replaced.
When the efficiency of the Tier 3 engine begins to deteriorate, Hathcock says it’s time to consider rebuilding it. However, if done correctly, a professionally rebuilt Tier 3 engine can live another 5 to 10 years, depending on how often it is used and whether it receives regular preventive maintenance.
If your engine requires repair or you’re thinking about rebuilding a Tier 3 engine, give MWI Repair a call at (772) 770-0004 or fill out a contact form to go over all of your maintenance and servicing choices.
Can Tier 4 engines be used indoors?
Lift truck manufacturers argue that the cost reductions from Tier 4 final models over prior models should outweigh the increased prices. Hyundai and Hyster, for example, hope to increase average fuel efficiency by 10% and 15%, respectively, in the models they plan to launch. In the meantime, both Mitsubishi and Cat have improved their fuel usage by 22%. However, Toyota may be the champion when it comes to fuel efficiency, claiming a 30% reduction in average fuel usage for its 8-Series diesel trucks when compared to the previous model.
These gains are the result of manufacturers’ concerted efforts to reduce fuel consumption—and consequently total cost of ownership—through innovations like regenerative braking, automatic engine shut-off, idle management, and on-demand hydraulic, cooling, and power steering. However, there may be hidden expenses. Diesel exhaust fluid (DEF), which includes around one-third urea and two-thirds water, is required by engines that use selective catalytic reduction technology. “Trucks that employ this technology require separate DEF tanks and regular fill-ups, which adds to the user’s costs,” Mayes explains.
According to the lift truck manufacturers, maintenance expenses should not be significantly higher. Cleaning will be required infrequently or not at all (in the case of DOC systems) depending on the type of emissions equipment. Some diesel particulate filters, for example, can last up to 4,000 hours before needing to be cleaned. The Tier 4 final engines, on the other hand, are highly electrical and hence “more sophisticated than previous diesel engines,” according to MCFA’s Dumdie. “As a result, troubleshooting them is somewhat different.”
The introduction of ultra-clean diesel engines is thought to be causing a shift in the lift truck market. For one thing, Webb believes that when prices fall, the cost difference between electric and IC trucks will be smaller than it is currently. “I believe the initial cost of a truck, battery, and charger will be more comparable to the original cost of a diesel truck.”
Furthermore, the Tier 4 final engines will be clean enough to be used indoors in some places, making them suitable for at least a few applications where they have previously been prohibited. In California, where the California Air Resources Board (CARB) has enforced fleet-wide emissions regulations, diesels may become more appealing. Instead of replacing older trucks with electrics or other power sources to maintain a fleet’s total emissions below the applicable limitations, Toyota’s Faiman claims that consumers might acquire the strong diesels they desire while still staying in compliance with the standards.
It’s possible that the problem will quickly spread to neighboring states. According to Faiman, the EPA has put off finalizing CARB’s diesel emissions guidelines for the time being, but if and when it does, other states with stringent air-quality goals may follow California’s lead and implement fleet emissions averaging as well.
Are Tier 4 engines more efficient?
Unfortunately, there are numerous misconceptions about the impact and performance of Tier 4 Final compliant engines in the power generation industry. We spoke with Darren Tasker, Vice President, Industrial, for Volvo Penta of the Americas, to get the full story.
A. Our Tier 4 Final engine technology has been tested in the field. In 2010, our sister company, Volvo Vehicles, was the first in North America to deploy Selective Catalytic Reduction (SCR) as a crucial part of the Tier 4 Final solution for over-the-road trucks. As a result, we can take advantage of this tried-and-true technology, which has been installed in over 270,000 trucks across the Americas.
A: When compared to natural gas, diesel fuel gives better efficiency and power per unit of volume. The design of the Volvo Penta Tier 4 Final application features built-in efficiencies that meet severe emission criteria while lowering particulate matter and NOx levels. The burning of natural gas engines produces carbon dioxide. Although natural gas burns cleaner and has lower running expenses than diesel, the startup cost of a natural gas system is higher than that of a Tier 4 Final system. Other factors to consider are:
(1) diesel fuel is less flammable than natural gas; (2) natural gas lines may be disrupted, shutting down the genset; (3) diesel engines require less maintenance than natural gas engines; and (4) while natural gas engines are often quieter than diesel engines, new mufflers and SCR catalysts significantly reduce the noise levels of a modern Tier 4 Final diesel.
Q. Is the fuel efficiency of Tier 4 Final engines comparable to that of earlier tier levels?
A. In fact, Volvo Penta’s Tier 4 Final engines are more fuel efficient due to the Engine Regulation Module’s precise control of the fuel-air mixture. The SCR technology has eliminated the requirement for extra Exhaust Gas Recirculation by lowering particulate matter and NOx in the engine (EGR). As a result, fuel consumption is lowered and reliability is improved.
Q: Will the Tier 4 Final engine’s additional complexity result in higher maintenance costs?
A: The Volvo Penta Tier 4 Final engine requires the same level of upkeep as earlier models. Our SCR system was created to be easy and dependable. SCR and non-cooled EGR are the only two significant components. The advantages are clear. There are fewer parts, which means there is a decreased chance of failure or malfunction. In addition, our SCR catalyst requires no maintenance.
A. It’s critical to consider the whole cost of ownership as well as the potential benefits. The cost savings from peak shaving, load control, and other electric market benefits often offset costs and help pay for the Tier 4 Final solution. In comparison to a Tier 2 system with aftertreatment, we have found that a Tier 4 Final certified system is actually less expensive in terms of initial acquisition and total cost of ownership. Better fuel efficiency, fewer maintenance costs, and less downtime are all part of our Tier 4 Final package. The SCR catalytic converter is also built to survive the lifetime of the engine.
Q. It is commonly asserted that modern emission-reducing engines have shorter lives than older engines. Is that correct?
A. Our engines release less NOx when they use a mix of SCR, non-cooled EGR, and an air throttle system. The amount of air that enters the engine is controlled by the air throttle, which affects the exhaust temperature, which dictates how much particulate matter is burned off by SCR. During light loads, the throttle closes slightly to maintain the engine temperature required to achieve those requirements. These aspects work together to produce a simple Tier 4 final solution that reduces engine wear and improves reliability.
A: In freezing conditions, Volvo Penta Tier 4 Final engines function identically to prior emission-step engines.
Q. Do the Tier 4 Final pollution regulations jeopardize the engines’ reliability in data center applications?
A. Traditionally, data centers have used pollution avoidance methods such as increasing stack height, which is highly expensive, or limiting working hours. A Tier 4 Final engine saves money on installation and allows for unrestricted use. In actuality, having the freedom to test and operate engines more frequently during system checkups and maintenance improves system reliability. Increased facility uptime is also a result of having the freedom to run an emergency backup system without constraint.
Q. What happens if the SCR system isn’t working properly, such as if the Diesel Exhaust Fluid (DEF) runs out?
A. There is fear that if the SCR system fails to minimize pollutants, the engine will automatically shut down. We collaborated with our electricity generation partners to develop a mechanism to reduce enticement. This is mostly accomplished by sizing the DEF tank to fit the fuel tank on site. This is due to the fact that diesel fuel and DEF are frequently provided by the same company. In addition, in accordance with Federal rules, there is an emergency inducement override that allows the Tier 4 Final system to continue running during an emergency event even if the SCR is not functioning effectively.
Q. Is it true that diesel particulate filters (DPFs) are required for all Tier 4 Final solutions?
A. To meet the criteria for particulate matter reduction, some Tier 4 Final engines from other manufacturers employ a DPF. DPFs have a disadvantage in that they require periodic downtime for regeneration. DPFs also have higher maintenance expenses and must be replaced more frequently. Without a DPF, Volvo Penta’s Tier 4 Final uses a more efficient and enhanced SCR technology to minimize particulate matter emissions.
What is a Tier 5 engine?
In what we’re calling the Tier 5 rulemaking, CARB staff is starting to work on potential modifications to the off-road diesel engine regulations. The Tier 5 rulemaking attempts to lower NOx and PM emissions from new, off-road compression-ignition (CI) engines compared to what is allowed under today’s Tier 4 final emission rules.
When did Tier 4 diesel engines come out?
The EPA’s Tier 4 engine emissions regulation is the most latest to be enacted. These Tier 4 emissions rules, which were signed in 2004, were phased in from 2008 to 2015.
Tier 4’s goal was to lower NOx and PM emissions significantly, although CO emission limitations remained same from Tier 3.
To meet emissions standards, Tier 4 added a new ultra-low sulfur diesel fuel. As we’ve become more familiar with ULSD as its use has risen, we’ve also come to appreciate all of its benefits and drawbacks.
In addition to sophisticated engine technologies and exhaust gas after-treatment systems, the new tier 4 standards have raised the bar for advanced engine technologies and exhaust gas after-treatment systems.
The cost of adding emissions devices was anticipated to be between 1-3 percent of the entire equipment cost. According to the EPA, the equipment’s increased expenses would be dwarfed by the gains in efficiency.
What is DEF on diesel?
We get a lot of questions about DEF and how to use it effectively on your forecourt, so we asked the expertise of Danny Seals, a forecourt solutions expert, to provide us with some simple answers.
What is DEF?
DEF is a urea-water solution that is injected into the exhaust stream of diesel automobiles to convert NOx gases (harmful emissions) into nitrogen and water. Vehicle manufacturers introduced a Selective Catalytic Reduction (SCR) technology to meet EPA emissions limits in 2010. This is a strategy to achieve the requirements without sacrificing engine performance or fuel economy. DEF isn’t a fuel additive, and it’s kept in its own tank.
Who needs DEF, why?
DEF is required for medium and heavy-duty vehicles equipped with diesel engines manufactured after 2010. To meet emissions rules, the vehicle is configured to inject DEF into the exhaust stream. The engine performance will be diminished and lower speeds will be imposed if the vehicle is allowed to run out of DEF.
What are the different delivery modes of DEF?
DEF is available in a variety of forms. A driver can purchase jugs/containers in a variety of sizes. This necessitates the driver physically transferring the DEF into the car. When installed, DEF can also be dispensed into the vehicle using a fueling dispenser.
Which retailers should offer DEF and what indicators can they use to decide?
Because there is such a vast population of automobiles on the road, DEF is an excellent product for all c-stores to offer. Retailers who sell diesel at their gas stations can utilize the volume sold to estimate the number of diesel customers they have. DEF is required by the majority of today’s heavy-duty trucks. Locations with a separate large truck filling station might think about putting DEF in the dispensers. Because they buy DEF in quantity to keep in their tanks, this results in higher profit margins. Some places that sell a lot of diesel on their forecourt should also consider a dispenser option.
How can Gilbarco help retailers get into DEF?
Since the inception of DEF requirements, Gilbarco has been the industry leader in DEF dispensers. Over the years, we’ve worked with large stores to provide dispenser functionality, and we’ve established the industry standard for this service. Gilbarco assists merchants in entering the DEF dispensing market by providing factory-installed options and retrofitting existing dispensers where DEF is stored in bulk.
What is a Tier 2 diesel engine?
CO stands for carbon monoxide; g/kW-hr stands for gram per kilowatt-hour; HC stands for hydrocarbons; THC stands for total hydrocarbon; kW stands for kilowatt; NOx stands for nitrogen oxides; PM stands for particulate matter; rpm stands for revolutions per minute.
Commercial compression-ignition (diesel) engines having a power rating of at least 37 kW are subject to Tier 2 emissions requirements set by Congress.
These specifications apply to both propulsion and auxiliary engines, however land-based engines used in portable auxiliary equipment must fulfill land-based engine standards.
A special rule applies to smaller compression-ignition engines. The US Environmental Protection Agency (EPA) also plans to regulate recreational marine diesel engine emissions under a separate rule, with exemptions for category 1 and 2 engines used as auxiliary engines in US-flagged vessels engaged in foreign trade or overseas operations for at least 75% of the time (i.e., operation will occur more than 320 nautical kilometers outside the United States, not including trips between U.S. ports in Alaska, Hawaii, the continental United States, or its territories).
Tier 1 emissions regulations are MARPOL Annex VI nitrogen oxide (NOx) limits (international norms adopted by the International Maritime Convention on the Prevention of Pollution from Ships).
These requirements apply to any diesel engine with a power rating of more than 130 kW installed on a vessel built on or after January 1, 2000, as well as any engine undergoing major conversion after that date. MARPOL standards are now optional for ships traveling within the United States, but will become mandatory for ships traveling internationally with countries that have ratified MARPOL standards. The EPA pushes engine manufacturers to create compliant engines and urges owners to purchase them, despite the fact that they have not yet been ratified by the United States. MARPOL Annex VI NOx regulations will be retrospectively effective on January 1, 2000 if ratified by the United States.
c Emissions requirements are determined by cylinder displacement and rated power. The three groups of standards are as follows:
These engines are typically employed as propulsion engines on relatively modest commercial vessels (category 1 = 37 kW) (fishing vessels, tugboats, crewboats, etc.). Auxiliary engines are also employed aboard vessels of all sizes and uses.
Category 2 (>= 5 liters displacement/cylinder to =37 kW): The largest engines utilized as propulsion engines in U.S. harbor and coastal vessels. Auxiliary power is also provided by these engines on very large ships. Many of these engines have the same size and configuration as locomotive engines, and they use similar emissions control systems.
Category 3 engines (displacement/cylinder > 30 liters, rated power.=37kW): These are exceptionally big, high-power engines that are virtually solely utilized for propulsion on international commerce vessels.
d Tier 2 marine engines with a power output of less than 37 kW must meet the same emission criteria as land-based engines.
g Engine or engine family manufacturers must show that the engine or engine family will meet all criteria for the duration of its useful life. Testing a sample of engines is used to determine useful life certification. Each engine manufactured is covered by a warranty period. Each engine’s manufacturer must provide a warranty to the ultimate purchaser or owner (and each subsequent purchaser or owner) that the engine is designed, built, and equipped to comply with Tier 2 standards at the time of sale and is free of defects in materials and workmanship that would cause the engine to fail to comply with these standards for the duration of the warranty period. Furthermore, this warranty must be at least one-half of the useful life duration and cannot be shorter than any mechanical warranty on the engine. The useful life is measured in hours or years, depending on whatever comes first.
Do Tier 4 Interim engines use DEF?
Tier 4 Interim and Tier 4 Final regulations are being sought in applications. SCR can reduce residual NOx in diesel engine exhaust by up to 90%. It works by mixing exhaust gases with ammonia in the form of urea (also known as diesel emissions fluid, or DEF) and passing the combination across a catalyst.
Do diesel tractors require DEF?
Checked 9 different brands! Since 2010, almost all diesel-powered trucks have been equipped with Selective Catalytic Reduction (SCR), which uses Diesel Exhaust Fluid (DEF) to assist reduce nitrogen oxide emissions (NOx).