ภาษาไทย
English
For all the car users, either small or big ones, regularly taking care of your car will not only extend its service life but will also help you reduce that unnecessary expense as you will be able to detect any malfunctions at their early stage before they turn into a bigger problem for the car in the future.
One easy way to do so is observing the color of the engine oil as it can tell you whether it is the time you should change the engine oil or not.
The new engine oil is transparent with a variety of tones ranging from light yellow to brown according to the composition of the oil which are base oil, additives, color dye depending on the manufacturer. The tone of the engine oil after being added into the engine will contain 5 to 10 percent contamination from the old oil that remains in the flow lines and other internal parts.
Therefore, the color of the engine oil added into the engine will differ in accordance with the old oil. The color of the engine oil in gasoline and diesel engines are different from the performance of the engine that affects the deterioration of the engine oil. The signs that you should observe are as follows:
For gasoline engines, under normal combustion, there will be less soot and dirt. Therefore, the change in the physical characteristics of the engine oil is mainly due to the deterioration of the oil from both heat and chemical reactions.
- Transparent engine oil
After adding the new oil into the engine, it is normal for the new oil to become darker even after just being used a few times due to the contamination of the old remaining oil. Therefore, if the engine oil still appears transparent with a slightly darker color, it means there are less contaminants from the normal combustion. This can indicate that the degradation of the oil is still low to moderate and can be continued to use until the specified period.
- Dark brown, dark or muddy engine oil
For engine oil that has been used for quite a period of time or has reached the schedule for oil changes, if the oil appears to be dark brown, burnt brown, black, highly contaminated with foreign substance or a significant change in condition (becomes significantly thicker) is found, it is recommend to have the oil changed as soon as possible to avoid severe engine damage due to the degradation of the engine oil and high contamination level.
- Milky, coffee-colored engine oil
This is mainly caused by large quantities of water leaking into the engine oil, such as leak in cylinder head, leak in water jacket, or water entering a rubber gasket, etc., resulting in the oil being cloudy and milky. This can be highly dangerous as water will catalyze the degradation of base oil and additives, hence the inability to protect the engine. There is also a chance of rusting and corrosion of internal metal parts. If the engine oil appears to be as mentioned, it should be changed immediately. Also, don’t forget to find the cause of the leak and fix it in order to prevent severe engine damage in the long run.
For diesel engines, incomplete combustion induces more soot and dirt than gasoline engines, especially in old technology engines and high-mileage cars where the fuel system is not working properly, more soot and dirt will build up inside the engine and contaminate the engine oil more.
- Black engine oil with no sludge
It is normal for oil in diesel engines to turn black immediately after being used due to engine performance and some residual contamination inside the old oil. If the used engine oil still remains free of soot and dirt that clumps together into large sludge or becomes muddy when checked, that means your engine oil still works effectively in controlling the engine cleanliness and dispersing soot and dirt to prevent clumping. This indicates that the deterioration of the oil is still low to moderate and can continue to be used until the specified changing period.
- Black engine oil with sludge
If the soot and dirt clumping together as a large sludge is found in the engine oil or the oil becomes muddy and cannot maintain the cleanliness of the engine when checked, this means the engine oil has degraded and the contamination is at a very high level and should no longer be used. This indicates that the oil should be changed immediately to prevent severe damage to the engine.
Observing the color of the engine oil and changing the oil at regular intervals will help keep the engine in perfect condition while also help save the money in our pockets so that we don't have to spend money on car repairs as well.
Notice: The color of the engine oil is only part of the assessment of the oil quality and what happens inside the engine as a result of use. It does not indicate all the problems. Engine conditions depend on the individual usage. It is recommended to check the condition of the car regularly and change the engine oil at the specified time.