Alternative method for determining the presence of gasoline in engine oil

The article discusses an alternative method is considered to determine the presence of motor gasoline in running engine oils. The test objects are working engine oils, samples of fresh oils produced by different manufacturers, and rapeseed oil. It is shown that the difference in the density and viscosity values of working oils from fresh oils is a reflection of changes in the properties of oils as a result of exposure to various factors. It was found that when gasoline and rapeseed oil were added to the samples of working and fresh oils, the rates of change in their viscosity were different. It is suggested that there is a relationship between the kinematic viscosity of the liquid and the content of motor oil, rapeseed oil and gasoline in it, which reflects the indicator ability of rapeseed oil to gasoline present in the oil that worked. This is confirmed by the difference in the values of relative changes in the kinematic viscosity of fresh and working oil after the introduction of rapeseed oil into them, which can be used as an indicator for gasoline present in the working oil. The presence of gasoline in the working oil, determined by the values of the relative change in viscosity, was confirmed by the data obtained by IR spectroscopy. Keywords: motor gasoline, fresh motor oil, used motor oil, kinematic viscosity, density, X-ray fluorescence analysis, regression analysis, full factorial experiment, relative change in kinematic viscosity