Under normal circumstances, the allowable water content in lubricating oil is below 0.03%. When the water content exceeds 0.1%, additives (antioxidants, dispersants, etc.) in lubricating oil will become ineffective, accelerating the oxidation process of the engine oil. The organic acids generated by oil oxidation and the acidic oxides in engine exhaust react with water to produce inorganic acids. These acidic substances increase the corrosion of the engine. Therefore, when there is a lot of water in the engine oil, the lubricity of the engine oil will deteriorate, the viscosity will decrease, and it may even lead to premature deterioration of the engine oil and rusting of the components; Severe mechanical accidents such as engine shaft jamming and tile burning may occur.
We try our best to avoid using engine oil that contains excessive moisture and to detect water in the oil as early as possible, in order to prevent damage to the engine caused by excessive moisture in the oil. In practical use, we can use some simple methods to determine whether the engine oil contains excessive moisture.
1. Color observation method
The engine oil that meets the cleanliness standards is semi transparent. The transparency of engine oil will decrease when water is present. When the engine runs for a period of time, the oil is milky white with foam.
2. Combustion method
After heating the copper mesh, put it into the inspected engine oil. If there is a "cracking" sound, it indicates that there is a lot of water in the engine oil. The inspected engine oil can also be injected into a test tube and heated. When the temperature approaches 80 to 100 ℃, a "crackling" sound is produced in the test tube, which also proves that the engine oil contains a lot of water.
3. Water release method
After the engine is stopped, let it stand still for about 30 minutes, then loosen the drain plug. If water is released, it indicates that there is a lot of water in the engine oil.
