Investigation of In-Use Deterioration of Exhaust Emissions from Small Single Cylinder Two Stroke-Cycle Engines

A Cross section of engines used to power hand held portable power equipment, both current production engines and engines designed to meet California's Tier I Exhaust Emission Limits (See Table #1), were subjected to actual field use and accelerated laboratory aging. Test data shows good correlation between actual field usage and accelerated laboratory aging. Both standard production and new lower emission type engines showed decreases in emissions during initial hours (0 - 10) and very minimal to no deterioration of engine exhaust emissions with respect to usage.