William B. Chamberlin

Balancing Crankcase Lubricant Performance with Catalyst Life

Emissions system durability may be influenced by many engine oil formulation variables. Previous studies have suggested that emissions system durability is optimized by high metal/phosphorus ratios. Reducing the level of phosphorus in the engine oils has also been suggested as a means of prolonging the efficiency of the catalytic converter. This paper explores engine oil formulation variables which may influence the efficiency of the emissions system. Phosphorus type and amount are examined as potential catalytic deactivators, as well as detergent metal interactions with the phosphorus. Dynamometer and over-the-road test data are presented which suggest that the volatility characteristics of the phosphorus component in the engine oil may influence the degree of catalyst contamination. To explore fully the many variables, however, will require an emissions performance test.

LUBRICATION EXPERIENCE IN METHANOL-FUELED ENGINES UNDER SHORT-TRIP SERVICE CONDITIONS

In order to assess the field needs of engine oils to be used in methanol-fueled vehicles, six oils were run in a fleet test over a ten-month period under short-trip service conditions. The results from the field test were compared with results with the six oils in the laboratory engine tests which have been used to predict field performance with methanol fuel. A lack of correlation between the field test and the laboratory engine tests suggests that the laboratory tests need revisions to better serve field needs.