发动机油底壳内的机油,由于与空气接触及受热,易被逐渐氧化。随着油中的酸性物质、胶质、铁屑、沥青质慢慢地增多,机油的颜色会渐渐变黑,黏度也会逐渐下降,同时性能降低,因而到了规定的换油期则必须更换新油。但在工作中发现,有时换油不久,机油又很快地变质,颜色由深蓝变黄,或是先变黑后突然变灰,失去了原有的技术性能。 Engine oil sump oil, due to contact with air and heat, easily be gradually oxidized. With the acidity in the oil, gum, iron filings, asphaltene slowly increased, the color of the oil will gradually darken, the viscosity will gradually decline, while reducing performance, so the provisions of the oil change period must be replaced oil. However, at work, it was found that sometimes oil changes quickly and sometimes, the oil deteriorates quickly, the color changes from dark blue to yellow, or the first darkening then suddenly becomes gray, losing its original technical performance.