The 4S shop said that if you spend more 100 yuan, you can replace the oil filter. Is it difficult?

Recently, a friend left a message saying that he went to change the oil in his car, and the store recommended that he could enjoy the VIP oil change method by adding 100 yuan, so that all the sludge residue in the oil pan could be pumped out and changed more cleanly. Is the effect of pumping oil really that good? Will you be cheated?

Pump oil and add a VIP. This store is a marketing genius! However, adding 100 yuan to become a VIP is not very valuable. Back to the topic, pumping can't be changed more cleanly, and it can't handle sludge and residue! In this issue, I will tell you about the tricks behind pumping! ? How does the oil pump work?

The principle of pumping oil is very simple, that is, pumping the old oil out of the oil pan with a pumping unit. The traditional method is to open the oil drain bolt on the oil pan and let the oil flow out by itself. Just like drinking a drink, pumping oil means drinking it through a straw, and draining oil means making a hole in the bottom of the bottle and flowing it out by itself.

Of course, when pumping oil, it is impossible for technicians to pump oil with their mouths. You have to get a pumping unit, insert the vacuum tube of the pumping unit into the oil pan through the hole of the oil drain gauge, and then start the pumping unit to pump out the old oil in the oil pan. The operation process is extremely simple. I really don't understand why it can be called VIP oil change method.

However, this pumping method is not suitable for all models. A car without a traditional dipstick cannot pump oil because there is no place to insert a vacuum tube. Now many models have cancelled the traditional dipstick and replaced it with an electronic dipstick, such as BMW. ? Can residue and sludge really be removed? ? Let's talk about residue first.

In fact, this matter will be understood after a little thought. The biggest function of oil machine filter is to filter residue, and the most residue left is oil machine filter, not oil pan. Replacing the oil filter element normally can avoid the situation of residue accumulation blocking the oil circuit. ? In addition, sludge

I'm afraid you haven't seen the sludge in the oil pan. The sludge in the oil pan is different from the sludge in the river, and it is soft. The sludge accumulated in the oil pan is as hard as carbon deposit and sprayed on it like paint, which may not be brushed off with a brush, let alone pumped off with a pumping unit.

There are two main reasons for sludge accumulation. The first is not changing oil for a long time, and the second is using inferior engine oil. As long as these two points are avoided, there will be basically no sludge accumulation. Therefore, the more thorough oil pumping is just pulling eggs, which is not substantially different from gravity oil changing, and is not worth 100 yuan. You can still use it if the merchant does it for you for free. ? Is pumping recommended just to make money? ? Making more money is only one aspect. There are also many shops that don't spend money, but they still use the method of pumping oil. The reason behind it is that I, the mechanic, have a deep feeling. ? Reduce labor intensity

The gravity oil change method should lift the car and drain the oil through the oil bottom bolt. At present, most models have engine lower guard plates, so it is a waste of time to remove the guard plates. In the aftermarket where efficiency is king, if others maintain it for half an hour, you can't maintain it for an hour. Isn't this interesting? Naturally, the sooner the technicians can, the better. There is no need to dismantle the guard plate and lift the car, and the oil pumping is obviously much faster. ? Avoid damaging accessories.

The oil bottom bolt of the engine is frequently disassembled, which is very worn. Improper operation is likely to overflow, but it just won't bite tightly. The bolt overflowed and began to leak oil, which could not be blocked at all. We have to replace the bolts. If it is serious, it may be necessary to replace the oil pan. There are also some automobile oil pans that are plastic, and the oil drain bolts are also plastic, so the risk of being damaged is extremely high.

It was not broken before it was dismantled, but it was broken after it was dismantled. The responsibility must belong to the technicians. Therefore, in order to avoid unnecessary troubles, many technicians simply don't move the oil pan screws.

In fact, pumping oil is more convenient and labor-saving than traditional pumping oil, so some manufacturers are gradually applying pumping oil replacement. Many models have separate reserved ports for pumping oil at the fuel filler. ? What's with the oil blowing? ? If the oil pump is VIP, then "oil blowing" is VVIP. "Blowing oil" is an upgraded version of pumping oil. Prices usually start at around 100 yuan, and high-end brands can even charge 200 yuan. Of course, some stores don't charge, but there are very few stores that don't charge. Shopkeepers usually say: "Blowing oil can blow out the residual oil in the internal pipeline of the engine, and the effect is the best!" Don't believe you, you must add more when you refuel! " This oil blower is interesting. It has just started in recent years. Let's talk slowly.

"Blowing oil" means blowing high-pressure air into the engine lubrication system to blow out the old oil left in the pipeline. The specific operation requires a special set of equipment. ?

Remove the oil filter, and then use a high-pressure air gun to blow air into the engine from the installation position of the oil filter. It is equivalent to blowing air into the bottle with your mouth, and then blowing off the water droplets attached to the bottle wall. The principle is exactly the same ~ how much oil will be left in the engine? ? In fact, what the merchant said is true. There is still engine oil in the engine, which cannot be released by gravity or pumping, accounting for about 10%~ 15%. In other words, the normal oil change amount of your car is 4L, so about 0.4L~0.6L of old oil can't be released.

You can only blow out a small amount of oil that you can't put out, and there is still a lot that you will never blow out. For example, the oil in parts such as oil radiator and variable timing adjusting wheel cannot be taken out without disassembly. Therefore, blowing oil is just a gimmick, and it doesn't have much substantive effect like pumping oil. It is even more inappropriate to spend money on it. ? In addition, there is no need to drain all the residual engine oil, which is totally unnecessary. As long as gravity displacement is enough to meet the requirements. Improving the quality of engine oil is more valuable than spending money to let it go.

There are also many people who say that high-pressure air contains a lot of water, and blowing oil may lead to too high water content in the engine lubrication system, which is easy to cause oil emulsification. In fact, this kind of worry is right, and there is such a risk in principle. This is directly related to the high-pressure air system in the maintenance workshop. At present, many high-pressure systems have automatic dehumidification function, and the water content is very small, so it is difficult to cause oil emulsification. Of course, the equipment level of each store is different, and the emulsification problem depends on the actual situation. ? What is the best way to change the oil? ? Gravity replacement after hot car? The most suitable way to change oil is to change it by gravity after hot car, without pumping or blowing. What exactly is a hot car? It is the center line from the water temperature to the water thermometer, which is about 90℃. At this time, the oil has the best fluidity and can release more oil to the maximum extent.

Many people say that when I go to change the oil, I always warm up the car. It was a hot car when I went, but it is not necessarily a hot car after changing the oil. If you catch up with the queue, it is not certain when it will last. If it is winter, the oil temperature will drop about ten minutes after the flameout, and the liquidity will obviously deteriorate. So many excellent technicians drain oil after the hot car in metropolis. Although the operation is a bit dangerous at this time, it may burn yourself, but there is a technician to change the oil after the hot car. ? In a word, pumping oil and blowing oil don't cost money. You can do it without spending money, but most of it costs money. Small maintenance is only a few hundred dollars, and it really doesn't make sense to spend a few hundred dollars on it.