Common sense of car use丨Can the oil left after maintenance continue to be used?

CNR Beijing, October 30 (Reporter Wang Zhan) Oil replacement is a must-do item for every vehicle maintenance. Whether it is major maintenance, small maintenance, A maintenance, or B maintenance, the oil filter needs to be replaced. It is because oil is the lubricant, cleaner and antiseptic inside the engine. Regular oil change can keep the vehicle engine in better working condition at all times.

In many cases, the capacity of a barrel of oil is not consistent with the capacity required for a single maintenance of the vehicle, so there will be some oil left after maintenance. Will the remaining oil go bad and can it be used again next time?

The answer is absolutely yes, but you also need to pay attention to the length of the interval and how to save it.

Generally, mainstream brand oil has a shelf life of 4 to 5 years if it is not opened. The general shelf life of the oil after opening is about one year, so if you want to “package” it and go home for the next maintenance, try not to exceed 1 year. In addition, whether the preservation method is appropriate will also greatly affect the shelf life of the remaining/unsealed oil.

There are two main reasons for the deterioration of engine oil: First, it is oxidized by contact with oxygen for a long time or by direct sunlight, resulting in poor lubrication effect, and some acidic substances will also be produced, which will cause corrosion to the engine.

Second, the moisture in the air is mixed into the oil, resulting in an increase in the water content of the oil and a weakening of the effect. Generally speaking, the normal oil water content is below 0.03%. When the water content exceeds 0.1%, the additives in the oil will fail and the oil will deteriorate.

Therefore, if you want to extend the shelf life of oil, you can start from the “reverse” of the above elements, that is, try to avoid contact with air and avoid water mixing into the oil.