Have you ever encountered the common problems of lubricating oil compound additives?

Have you ever encountered the common problems of lubricating oil compound additives?

Can the color of engine oil reflect the performance of engine oil?

1. The color of engine oil depends on the formula of base oil and additives. Different formulas of base oil and additives will make the engine oil show different colors.

The performance of engine oil is evaluated through a series of engine bench tests and real vehicle road tests. These tests test the performance of engine oil from oxidation, corrosion, sediment, adhesive ring, sludge, scratch, wear and so on.

Is the oil that can turn black bad

2. Not necessarily. Some excellent engine oils contain additives that can dissolve carbon deposits in the engine, so they are easy to turn black, but they have no impact on the performance of the engine oil.

Why change the oil regularly?

3. The engine oil will deteriorate gradually during operation. The main reasons are:

·Combustion by-products: such as water, acid substances, soot, carbon deposition, etc.

·Fuel dilution

·High temperature oxidation deterioration of engine oil itself

·Dust and metal particles

These substances are contained in the engine oil. At the same time, the additives in the engine oil will be consumed with the use process. Failure to change the engine oil on schedule will significantly reduce the anti-wear protection of the engine oil.

Changing the engine oil can not only discharge the pollutants in the oil, but also ensure that the components in the engine oil are kept at a reasonable level.

Why is the oil released very thin when changing the oil?

4. When changing the engine oil, it is usually carried out in the hot vehicle state. The viscosity of the engine oil decreases with the increase of temperature. Therefore, the viscosity of the engine oil with higher temperature is thinner than that at room temperature, which is a normal phenomenon.

However, when the temperature drops to room temperature, the oil viscosity is still very low, which is likely to be caused by fuel dilution during the use of the oil.

How to check the quality of oil in use

5. Appearance:

·The oil sample is milky white or foggy, indicating that the engine oil has water;

·The oil sample turns gray and may be polluted by gasoline;

·Black, caused by products of incomplete combustion of fuel;

Odor:

·Pungent smell indicates that the engine oil is oxidized at high temperature;

·Heavy fuel smell indicates that it is seriously diluted by fuel (a small amount of used engine oil has normal fuel smell)

Oil drop spot test: drop a drop of engine oil on the filter paper and observe the change of spots

·The oil diffuses rapidly and there is no sediment in the middle, indicating that the oil is normal;

·The oil diffuses slowly and deposits appear in the middle, indicating that the oil has become dirty and should be replaced in time.

Burst test:

Heat the thin metal sheet above 110 ℃ and drop a drop of engine oil. If the oil bursts, it proves that the engine oil contains water. This method can detect the water content of more than 0.2%.

What are the reasons why the oil alarm light is on?

6. The oil lamp on is mainly caused by insufficient oil pressure in the lubrication system, usually due to the following reasons:

·The oil in the oil pan is insufficient, and check whether there is oil leakage caused by loose sealing.

·The oil is diluted by the fuel or the engine is overloaded and the operating temperature is too high, resulting in the thinning of the oil viscosity.

·The oil passage is blocked or the oil is too dirty, resulting in poor oil supply to the lubrication system

·The oil pump or oil pressure limiting valve or bypass valve is stuck and does not work well.

·The fitting clearance of lubricating parts is too large, such as serious wear of crankshaft main bearing journal and bearing bush, connecting rod journal and bearing bush, or peeling of bearing bush alloy, resulting in too large clearance, increasing oil leakage and reducing oil pressure in the main oil passage.

·The oil pressure sensor is not working properly.

·The viscosity of the oil is not correctly selected according to the climate and engine operating conditions.

The oil with low viscosity is selected to increase the oil leakage of lubricating parts and reduce the pressure of main oil passage. The selection of engine oil with too high viscosity (especially in winter) makes it difficult for the oil pump to pump oil or the engine oil filter to pass through, resulting in low system oil pressure.