This year’s International Consumer Rights Day, 315, seems to be much duller than in previous years, but many consumers have come forward to defend their rights and report complaints. For example, users of Apple, Xiaomi, OPPO and other brands have complained about automatic deductions.
The automobile industry is no exception. Car owners of Mercedes-Benz, Honda, Toyota, Changan, Dongfeng Citroen and other brands have also complained a lot about the problems of "increased engine oil" and "oil emulsification". It can be seen that this is a problem. A very common question is not which car is "patented". Following the Dongfeng Honda CR-V's unexplained increase in engine oil, which caused northern car owners to collectively defend their rights and eventually recalled 130,000 vehicles, why do the same situations often occur? Next, let’s explore the reasons together.
Anyone who knows something about cars knows that a sudden increase or decrease in engine oil and oil emulsification are abnormal. When these two situations occur, it may be that impurities are mixed into the engine oil, which will affect the performance of the engine oil. Therefore, once such a situation occurs, it is recommended to have the vehicle inspected, just in case. However, there are also situations where other impurities will inevitably be mixed into the engine oil and you don’t need to worry too much about it, and that is crankcase blowby.
Exploring the Principle of Increased Engine Oil
Crankcase blow-by is a phenomenon that exists in every engine. No matter what brand or engine displacement, there will be crankcase blow-by, so there is no need to Worry too much. Next, let’s take a look at why crankcase blow-by occurs, leading to an increase in engine oil.
After Honda received the complaint before, it made a detailed technical analysis and explanation. Many people in the industry also understood that the gasoline attached to the cylinder wall would escape into the crankcase through the oil ring. At the same time, The condensation effect of the temperature difference between the inside and outside of the engine will also bring water vapor and some exhaust gas. Under normal circumstances, because the engine will be equipped with a forced crankcase ventilation system, also known as a PCV system, the oil, gas and wastewater will be separated through the PCV valve and the oil-gas separator, and the oil will be guided back to the crankcase, and the evaporated gasoline and water vapor will be introduced into the engine. The gas manifold is sucked into the combustion chamber for secondary combustion without much impact.
The "abnormal" situation is that when the car owner drives the vehicle for a short distance in the cold season, the oil vapor that escapes into the crankcase stays in the crankcase and mixes with the engine oil without being evaporated. That is to say, because the temperature is too low, the volatility of gasoline is reduced, gasoline and engine oil are mixed together, and the engine stops working before it heats up. Over time, an increase in engine oil will occur.
This just explains why car owners in the north account for a larger proportion of complaints about increased engine oil, while there are fewer car owners in the south. In short, it is safe if the oil increases within a certain range and does not exceed the alarm limit. If you encounter this situation, you don't need to panic too much.
Study on the principle of engine oil emulsification
As the amount of engine oil increases, the so-called "oil emulsification" problem will also occur. Some car owners will find a milky white sticky substance on the oil cap after unscrewing it. Why is this? The first thing I want to tell you is that the emulsification of the oil cap is not the same as the emulsification of the engine oil. The two are completely different. What most car owners encounter is actually the emulsification of the oil cap, which will not directly affect the working condition of the engine.
How to judge whether the oil cap is emulsified or the engine oil is emulsified? In fact, it is easy to handle. If there is indeed an impact of engine oil emulsification on the engine, the car owner will be able to feel it during driving. If there is no increase in fuel consumption or difficulty in acceleration, you don't have to worry too much if you just find emulsification on the oil cap.
In fact, when analyzing "increased engine oil", it was mentioned earlier that water vapor and exhaust gas were mixed into the crankcase, but they were not evaporated in time before the engine was turned off and stopped. Like during the current epidemic, when a vehicle is parked for a long time, oil and water will separate everywhere. Some of the water will be discharged with waste, and some will condense at the oil filler cap. Coupled with the large temperature difference, it will Emulsification is prone to occur.
If you encounter the above two situations, don’t worry. You just need to "warm up" the engine while driving and wait for a while before getting on the road. If you are a car owner who often drives short distances, you can go for a drive. After the engine is running normally, the emulsion will disappear as the engine temperature increases, and it will not be a big problem.
This article comes from the author of Autohome Chejiahao and does not represent the views and positions of Autohome.