1. If the engine oil is insufficient, it will lead to the increase of friction between the relatively moving parts of the engine, the increase of motion resistance, the decrease of engine power and the inability to accelerate;
2. The moving engine oil can remove the garbage and carbon deposits on the surface of the relatively moving parts, and radiate the heat generated by the relative friction movement. The engine without engine oil will pull or explode, and the engine parts without engine oil will be seriously worn, which will affect the service life and driving safety of the locomotive.
3. Under the condition of insufficient engine oil, if the engine runs under the condition of insufficient lubrication, poor sealing and insufficient heat dissipation, excessive wear and tear will occur, or even severe local wear and tear will be caused, which will seriously lead to engine scrapping.