Why does industrial lubricant engine oil turn black?


(1) Oxidation of engine oil Oxidation is determined by […]

(1) Oxidation of engine oil

Oxidation is determined by the temperature, time, performance of the base oil and antioxidant additives. Therefore, oxidation takes a certain amount of time. Generally speaking, the color of the oil does not become deeper due to oxidation, and it does not become dark soon.

(2) Driving conditions of the vehicle

Turbine oil operates at higher temperatures at full load and its cooling system is designed for continuous operation at full load. If the vehicle is turned on and off for some reason, such an engine is operating in a "cold" condition, ie operating below the design temperature. At this time, the gasoline is particularly prone to form part of the oxide, breaks into the crankcase, shrinks into oil-insoluble droplets, and firmly adheres to the metal surface when it returns to the piston ring area, and is converted into a semi-solid or solid lacquer deposit by heat. Object. In addition, the lubricating oil will also be nitrated to form deposits, which is accelerated by the NOx of helium. All of these deposits, if they are flushed out in time by a lubricant containing a clean dispersing additive, can be filtered out, which is very beneficial for engine maintenance.

During the use of the diesel engine, the oil becomes black and the speed is very fast. This is due to the large amount of soot generated by the combustion of the diesel, the intrusion into the crankcase, and the dissolution in the oil. In general, the higher the grade of diesel engine oil is used on the same engine, the faster the blackening speed and the darker the color.

Some customers used inferior oils before, and now they use high-quality oil, the oil will quickly turn black, which is the result of the dirty internal combustion of the engine and the high-efficiency detergent dispersant of high-quality engine oil.

In general, it is normal for the oil to turn black during use. The speed at which the oil discolors depends on the driving condition of the vehicle, the driving conditions, the design of the engine, the quality of the fuel, and the quality of the oil.