Oil filter - Knowledge You Don't Know

Every time the car is maintained, the small tin can on the car must be unscrewed and replaced. This is our oil filter. Replace it together with the random oil.

So the question arises: How often should this oil filter be replaced every kilometer? What is its longest lifespan? How long is its replacement cycle?

Before delving into this issue, let's first take a look at this oil filter.

The oil filters we currently have are basically of this spin-on type. Outside is a circular iron box, and inside are folded filter papers. This kind of filter paper is the core material of our machine filter. The current machine filter paper is heat-cured, so it has a certain degree of hardness and strength. Unlike our ordinary paper, it can withstand oil pressure and is not easy to deform.

The oil filter is screwed into the middle part of the oil circuit. The bottom is the oil pan and the top is the engine. Its main function is to filter impurities and dirt in the engine oil, provide clean lubricating oil for the engine, reduce wear and extend the service life of the engine.

This is how it works. It has an oil inlet and an oil outlet. The oil in the oil pan flows into the filter through the oil inlet check valve. The dirty oil flowing in is at the edge of the filter, on the outside of the filter paper, and then filtered through the filter paper. Clean engine oil flows out from the center of the filter and is sprayed onto all parts of the engine.

This is a normal working process, but there will be some special circumstances. For instance, if our machine filter has been in use for a long time and the filter paper contains too many impurities, blocking the filter paper holes, it will cause oil to flow out. If the amount used decreases, less engine oil will enter the engine, which will affect the lubrication and operation of the engine. What should I do?

In fact, at this time, in order to ensure the amount of engine oil flowing into the engine and maintain the oil pressure, there is a spring valve at the bottom of the oil filter, called the bypass valve. It will automatically open to allow the unfiltered oil to flow out from the bottom valve. It goes in and converges with the engine oil at the center of the filter, flowing into the engine together. However, at this point, the mixed engine oil is impulent.

How long can a machine filter be used?

In fact, the quality of our machine filter is not a problem. The filter paper will not deform due to oil pressure and soaking in a short time.

However, the service life of a machine filter is mainly judged by its filtering capacity rather than its own quality. Just now we mentioned that if there are too many impurities and grease in the engine oil, they will adhere to the filter paper, clog the filter holes, cause the engine oil pressure to drop, and thus allow the impure engine oil to directly enter the engine. This is equivalent to the engine oil not being filtered. In fact, it is already time to replace the filter element at this point.

Therefore, the replacement of the machine filter depends on the cleanliness of the oil. Let's take an example. For example, we changed the engine oil and the filter element. If we have run 5,000 kilometers for maintenance without changing the oil, we only replace the filter element, but the time for the next replacement of the filter element will not reach 5,000. Every kilometer, perhaps 2,000 kilometers or 3,000 kilometers, it needs to be changed because the old engine oil has more impurities than the new one.

Therefore, in most cases, the service life of the oil filter is 5,000 kilometers and it is for new oil.