Oil Filters in Public Utility Fleet Operation 370168
THIS paper has to do mainly with the care of the oil while in service, which care is considered as important, or more so, than its selection. The author points out that at present there is no reliable scientific method or test for determining whether or not an oil is suitable for further use, and that oils do not wear out but simply become contaminated with various impurities.
Impurities that tend to produce changes in the characteristics of crankcase oils while in service are considered under headings of inherent impurities and extraneous or foreign impurities. A number of types of filters are discussed with the various types of elements in use. Desirable features of a good filter are enumerated.
Although admittedly a controversial issue, the author believes that filters are decidedly advantageous and economically justifiable especially from the standpoints of fewer oil changes, decreased oil consumption, and reduced bearing and cylinder wear.
A discussion of the time when a filter element should be changed concludes the paper.