Used oil analysis is an important part of engine maintenance. It provides information about the condition of the oil, its suitability for further use and to a certain extent information about the condition of the machinery lubricated by the oil. Precondition of a valuable oil analysis and its interpretation is a sample being taken according to a reliable procedure.
Besides routine methods used in all engine oil analyses, there are several advanced methods that provide additional information. Both routine and advanced methods are described and it is discussed how they can be interpreted for 4-stroke and 2-stroke engine applications.
This recommendation No. 30 is intended to enable its reader to better understand the analysis of a used oil sample, to realise the limitations of some methods, to develop ideas on how to increase reliability and safety of the installation onboard as well as provide insight into used oil analysis as a trouble-shooting tool.