A Comparison of Engine Oil Viscosity, Emulsion Formation, and Chemical Changes for M85 and Gasoline-Fueled Vehicles in Short-Trip Service 922297
Accumulation of fuel, water, acids, insolubles, and metals in engine oil is documented and compared for variable-fueled (fuel containing up to 85 percent methanol) and gasoline-fueled vehicles in short-trip service. The oil temperature at which various contaminants are removed is noted. As a consequence of emulsion formation, the viscosity of the oil in the M85-fueled vehicles increased. Due to the presence of gasoline, the viscosity of the oil in the gasoline-fueled vehicles decreased. Equations were developed to explain both the viscosity reduction due to gasoline and the viscosity increase due to emulsion-forming contaminants (water and methanol).
Citation: Schwartz, S., "A Comparison of Engine Oil Viscosity, Emulsion Formation, and Chemical Changes for M85 and Gasoline-Fueled Vehicles in Short-Trip Service," SAE Technical Paper 922297, 1992, https://doi.org/10.4271/922297. Download Citation
Shirley E. Schwartz
General Motors Research and Environmental Staff
International Fuels & Lubricants Meeting & Exposition
Passenger Car Engine Lubricants-SP-0939, SAE 1992 Transactions: Journal of Fuels & Lubricants-V101-4