在农村不少机手不能正确换用发动机机油 ,往往换了新机油 ,起不到好作用 ,造成不应有的损失。有相当多的机手在给发动机换机油时图省事 ,放掉旧机油 ,加入新机油了事 ,甚至连机油滤清器也不清洗。这种作法是错误的 ,因为发动机润滑油路内各部位都存有大量机械杂质 ,相当一部分 In the countryside, quite a few handlers can not switch engine oil correctly, often changing new oil, failing to play a good role and causing undue losses. There are quite a few hands in saving engine when it comes to changing the oil, let go of the old oil, add new oil trouble, and even the oil filter does not clean. This approach is wrong, because the engine lubricating oil in various parts of the road there are a lot of mechanical impurities, a considerable part