Testing the Gasoline Dilution Rate of Gasoline in Engine Oil in Accordance with ASTM D3525 and Japan Petroleum Institute Standard JPI-5S-24

Introduction

If gasoline or diesel mixes into the engine oil, it decreases the oil viscosity and prevents achieving the proper performance as a lubricating oil. Measuring the fuel dilution rate serves as a key indicator during oil replacement, because it can determine the degradation status of engine oil. The test methods used to measure the fuel dilution rate are specified in standards such as U.S. ASTM D3524, D3525, and D7593. The standard for gasoline is ASTM D3525. It corresponds to the Japan Petroleum Institute standard JPI-5S-24 in Japan. This article describes an example of measuring the dilution rate of gasoline in engine oil in accordance with ASTM and JPI standards.

June 25, 2023 GMT