An independent study of a similar nature to that made by the Bureau of Standards on fuels in 1923 was conducted by the company the author represents, and the paper presents first the results of the tests made on five 7½-ton trucks during the regular course of business deliveries. Curves plotted from the data thus obtained are presented and analyzed in considerable detail.
These data were then utilized as a basis for a series of dynamometer experiments in an attempt to explain further the effects of the many temperature and mechanical variables on the rate of oil consumption and oil dilution when only one factor was allowed to vary at a time.
The dynamometer apparatus and the engine used are described, together with the test routine, and an analysis is made of the result of wear of the test engine. The “standard” conditions under which the test runs were made are stated. Each series of runs was made by varying only one of these standard variables at a time; all others were held constant. The runs of Series A relate to carbureter setting, and those for the subsequent series have to do with load, oil volume, crankcase temperatures, carbureter air-temperature, cylinder-jacket temperature and engine speed. Curves plotted from data obtained in each series of tests are presented and analyzed, and, as an indication
of the general trend of the results that may help to solve some of the perplexing lubrication problems now current, five tentative conclusions are specified.