介绍了DF4C型机车发生机油乳化后不及时发现的严重后果 ,阐述了造成机油乳化的途径、判断机油乳化的方法及处理的具体步骤 This paper introduces the serious consequences that the DF4C locomotive did not detect in time after the emulsification of the engine oil. It also elaborates the ways of emulsifying the engine oil, the method of judging the oil emulsification and the concrete steps of the process