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Heavy Equipment Maintenance: Tier IV Engine Tips

One of the most important parts of heavy equipment maintenance is properly handling their Tier IV engines. These engines are engineered with highly effective emission control systems to reduce environmental impact and improve fuel efficiency and overall performance. In this article, we are going to cover all the basics of Tier IV engines and how they fit into wider heavy equipment maintenance.

Types of Tier IV engines

Tier IV engines are designed to meet the strict emissions regulations implemented by the EPA. Their systems minimize harmful pollutants normally produced by diesel engines, including nitrogen oxides (NOx), particulate matter (PM), and carbon monoxide (CO). There are two types of Tier IV engines that neutralize these pollutants in different ways.

CEGR - CEGR uses an exhaust gas recirculation cooler (EGR) to lower the combustion temperature of the engine through mixing fresh air with exhaust gas. Particulates and pollutants are caught by a diesel particulate filter (DPF) to prevent them from entering the environment. The emissions that are released are less harmful N2 and CO2 gases.

SCR – Selective Catalytic Reduction relies on a liquid reductant agent called diesel exhaust fluid (DEF), which is added through a special catalyst into the exhaust stream of the Tier IV engine. It causes a chemical reaction that turns nitrogen oxide into harmless nitrogen and water.

Both types of Tier IV engines make equipment more efficient and use significantly less fuel than older machines, reducing their carbon footprint and environmental impact. Despite their emission control systems, Tier IV engines improve performance without reducing power.

Heavy equipment maintenance tips for Tier IV engines

Use the right diesel

High quality, low sulfur diesel fuel is required by both types of Tier IV engines and also the EPA. Using low grade diesel may cause clogs in your fuel system, lead to more emissions, and will hurt equipment performance. If you use fuel that is not ultra low sulfur it can cause costly damage to your machine’s fuel system, DPF, or exhaust after treatment system. Plus, if you violate the EPA’s low sulfur requirements, you may also be fined.

Choose the correct oils

Tier IV engines need CJ4 oils, because they are engineered to operate with their aftertreatment systems. Using the wrong oil in your equipment may damage the machine’s emissions components and cause costly repairs and downtime. We recommend switching your entire fleet to CJ4 oils, so that you don’t accidently place the wrong type of oil in your Tier IV machines. CJ4 oils will not hurt your older, non Tier IV machines.

Properly maintain your DPF

A key part of heavy equipment maintenance is correctly servicing your DPFs. Most diesel particulate filters (DPFs) last at least about 3,000 to 3,500 hours and are cleaned through a regeneration process that occurs while the filter is on the machine. When it comes time to replace the filter, check your owner's manual to determine its exact location on your specific piece of equipment.

Don’t forget about DEF

Refilling the diesel exhaust fluid (DEF) tank should be part of your regular heavy equipment maintenance or refueling routine. Equipment that uses DEF has a gauge and a warning signal when the fluid level is low, just like a fuel gauge. It’s crucial to always be proactive about checking the DEF levels, and replacing the supply module filter at the interval recommended by the manufacturer.

If you have any questions about Tier IV engines or heavy equipment maintenance, our team today!

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