Technical Paper
Winter Oils for Automobile Engines
1934-01-01
340098
THE factors involved in cold starting of automobile engines, including the effects of temperature and oil viscosity on cranking speed and torque, have been known for many years. Many papers have been presented before the various Sections of the Society on these subjects. The S.A.E. crankcase-oil viscosity-numbers, which were adopted in July, 1926, provided for the classification of the lower-viscosity oils at 130 deg. fahr. and the higher-viscosity oils at 210 deg. fahr. It was recognized by 1930 that a classification for winter oils must be based on the viscosity of the oil at the starting temperature, and work was started on this problem. In June, 1933, the 10-W and 20-W oils, which are classified in accord with their viscosity at 0 deg. fahr., were adopted for publication and trial. The results of the use of these oils during the winter of 1933-1934, together with their advantages, are discussed.