The Effect of Lubricating Oil Volatility on Diesel Emissions

This paper discusses the role that lubricant volatility plays in the generation of particulate and other regulated emissions from diesel engines and presents a new technique for continuously controlling oil volatility and thereby reducing visible smoke, particulates, carbon monoxide, and hydrocarbons.

Test results are presented that indicate that a major reduction in particulate emissions can be attained through the elimination, by continuous evaporation, of light lubricating oil fractions. The effects of treatment temperature on regulated emissions are detailed through a series of single cylinder engine tests.

The results of in-service vehicle trials are presented and indicate 40-50% reductions in visible smoke in snap idle tests and reductions in regulated emissions on a number of other test cycles. Monitoring of oil characteristics in the long-term trial indicates that critical oil characteristics are maintained for longer periods than that of control vehicles' oil.