Abstract
Engine oil is a substance used for the lubrication of internal combustion systems. However, in some case, defects in engine systems may contaminate engine oil with fuel. Contaminated engine oil can cause problems in the normal functioning of a vehicle. In this study, we investigate the functional properties of engine oil contaminated with diesel fuel. The test results indicate that the engine oil contaminated with diesel fuel has low flash point, pour point, density, kinematic viscosity and cold cranking simulator value. The contaminated engine oil which has low plash point can cause fire and explosion accident. Furthermore, a four ball test indicates that the contaminated engine oil increases wear scar to poor lubricity. Moreover, we investigate the GC pattern using SIMDIST (simulated distillation) for determination of diesel in engine oil. The SIMDIST analytic result, diesel was detected at earlier retention time than engine oil in chromatogram. Thus the SIMDIST method can define whether engine oil is contaminated by diesel fuel or not. We can use the SIMDIST method for the diagnosis of oil condition instead of analyzing other physical properties that require many analytic instruments, large volume of oil sample and long analysis time.