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On Thursday, the U.S. EPA finalized changes to its non-road engine rules including clarifying the use of replacement engines and providing additional flexibility in regards to the issuance of technical hardship exemptions for Tier 4 non-road engines. The replacement engine changes continue the practice of allowing manufactures to build and sell new engines intended to be used in existing equipment. Under the replacement program, manufacturers can sell engines that either meet standards that applied at the time the replaced engine was manufactured or satisfy more recent emission standards. Thus, these new replacement engines are exempted from having to meet the more demanding standards currently in place. This flexibility is intended to address the situation where engines certified to newer emission levels are not available to replace a failed engine. As EPA notes, this exemption provides equipment owners the ability to keep equipment in the field that otherwise would have to be prematurely scrapped. The new rules clarify that the exemption only applies to equipment that is 40 years or less in age. Similar restrictions apply to stationary engines but, in that case, the age limit is 15 years or less in age. If an equipment operator wants to replace an engine that has not failed (e.g., wants to upgrade or repower with a newer, more efficient engine), EPA rules require selection of a “replacement engine that is designed with the greatest degree of emission control.” Factors that can be considered in determining whether a suitable engine is available include physical and performance characteristics.

The rules also address the ability of manufacturer to reclaim replaced engines and to use the old engine block. If the engine block is placed in a new vehicle it must meet current emission standards, but, if it is rebuilt with the intent of being used as a replacement engine for a failed engine, it can be rebuilt to the same emission standards as the failed engine. The final rule also includes additional flexibility and more time for equipment manufacturers who are facing difficulty in obtaining engines that meet the new Tier 4 standards. As noted above, these rules are somewhat complicated and affected manufacturers or equipment operators should carefully review the final rule. To view the final rule, click here.