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The cold pumpability characteristics of a group of commercial premium crankcase oils were evaluated at 0 and -20 F in a test stand engine. A test procedure was developed for these evaluations which gave results that compared favorably with those obtained in two popular makes of test cars at 0 F. In a second, more detailed, phase of this study, the effects of fourteen factors on the cold pumpability of several crankcase oils were investigated. The data from both phases were then analyzed to determine if an oil's cold pumpability in an engine could be predicted from its CCS viscosity, Brookfield viscosity, GM pour time, or ASTM pour point.

The cold pumpability characteristics of nine commercial crankcase oils were evaluated using a V-8 engine and a bench test. These nine oils included most of the SAE viscosity classifications. The engine data were used for evaluating the ability of the bench test to predict the cold pumpability properties of crankcase oils. Additional tests were conducted to study some unusual cold pumping properties of two of the oils. One of these oils was very soak-time sensitive, while the other was found to improve in pumpability after only brief use in the test engine.

The influence of lubricating oil formulation on the winter hot-starting torque requirements of an automotive engine was investigated in a four part study. Commercial multi-grade oils, V.I. improved oils, oils containing oiliness agents, and experimental oils in the new and used condition were evaluated for their low speed, hot cranking torque requirements. These torque requirements were determined using a test stand engine equipped to measure cranking torques at selected cranking speeds from 5–236 rpm. The ASTMD 445 viscosities at 210 F were shown to be inadequate for predicting the low speed, hot cranking torque requirements of the oils evaluated in this study. Several oiliness agents effectively reduced the low speed, hot cranking torque requirements of a crankcase oil.

A reciprocating viscometer which was used for determining cold-cranking properties of engine oils was modified so it could be used to predict low-speed, hot-cranking properties of crankcase oils in full-scale engines. Since the current 210 F ASTM D 445 viscosities of multigrade oils fail to predict their hot-cranking properties, there is need for such a unit. A high degree of correlation was obtained between the 210 F viscosities determined with the modified reciprocating viscometer and those determined using a full-scale test engine for a group of V.I. improved oils and a group of commercial premium multigrade crankcase oils. The correlation obtained between the two units for a group of 5W oils containing oiliness agents indicates the viscometer to be satisfactory for screening tests. In general, this viscometer can satisfactorily predict low-speed, hot-cranking properties of oils in full-scale engines quickly and economically.