Quantitative evaluation method of engine oil-derived deposit

Abstract

A quantitative evaluation method of an engine oil-derived deposit includes pre-processing, generating a deposit, and measuring an amount of deposit generation. In an inert gas atmosphere, the pre-processing heats engine oil to 270° C. or higher and holds the engine oil at the heated temperature in a predetermined period of time. In an air atmosphere, the generating the deposit sets the engine oil having undergone the pre-processing at a fixed temperature and holds the engine oil for 120 minutes or more at the set temperature. The measuring the amount of deposit generation measures the amount of generation of the deposit generated in the generating the deposit.

Dependencies are inferred from the claim text.