Development of an Engine Screening Test to Study the Effect of Methanol Fuel on Crankcase Oils

An engine screening test has been successfully developed to study the effect on bore and ring wear of crankcase oils in methanol-fueled spark ignition engines. The cyclical Sequence V-D test procedure was modified and used in the 2. 3L engine for this development. The main modifications were as follows: The engine was equipped with an oil filter dual carburetors and an oil flushing mechanism.

The metals content in the used oil samples were monitored as a bore and ring wear indicator and oil quality was differentiated effectively in 4 to 22 hours of testing. As a result two fully formulated oils have been defined. The performance of these oils exceeds the SF specification limits in methanol-fueled V-D testing and reduces bore and ring wear to almost the same levels as typically seen in gasoline-fueled engines. These products are now undergoing extensive field evaluation.