The purpose of this Work Assignment was to assess the emissions from various nonroad diesel engines using nonroad and highway fuels. Regulated exhaust emissions (HC, CO, NOx, and PM) information was generated for both steady-state and transient engine operation from a total of nine in-use heavy-duty nonroad diesel engines. There were three agricultural tractor engines greater than 175 hp, three engines greater than 175 hp from construction equipment, and three engines less than 175 hp from construction equipment. The model years of the engines tested ranged from 1988 to 1997. This report also documents repairs that were required on four of the nine engines before testing could be performed. Data from this Work Assignment will be useful in assessing the nonroad emissions inventory.

Prepared for U.S. Environmental Protection Agency [Office of Mobile Sources, Ann Arbor MI].