Most car owners change their antifreeze during winter, and some people have strong hands-on skills and choose to purchase their own antifreeze to replace it themselves. The replacement method is also very simple, just remove the old antifreeze and add a new one. But in practical operation, there may be some problems, which are more troublesome than changing the oil. There are generally three major problems: one is that the antifreeze cannot be drained clean, the second is that the water temperature is high after replacing the antifreeze, and the third is that there is leakage after replacing it. Let's elaborate on these three issues below.
        
  Firstly, how to release the old antifreeze? Some cars have a drain hole at the bottom of the water tank, which can be drained by simply screwing the water bolt. This is the simplest and the antifreeze flow is relatively clean. Some cars do not have a drain hole and need to remove the water pipe, which is relatively troublesome and not easy to operate by oneself. Additionally, there is a risk of leakage after reinstalling the water pipe. At a 4S store, high-pressure gas is usually used to blow it out to make it more thorough. We don't have compressed air to blow ourselves, we can only rely on it to naturally flow out and not release it too thoroughly, which is also unavoidable. Although it's not thorough, it's not much different, so there's no need to get too tangled up. Even if replaced at a 4S store, different technicians may release different amounts of antifreeze, and some may not be able to be cleaned. When installing the water pipe, it is necessary to clean the rust and impurities on the pipe wall. It is best to clamp the water pipe clamp according to the original marks, and generally there will be no leakage. If there is water pipe sealant, you can also apply a little bit, which is safer.

        
Secondly, there is a relatively serious problem, which is that after changing the antifreeze, some cars may experience high water temperature. After starting the car for a while, the fan began to rotate at high speed, but the water temperature was very high. This situation is generally caused by air blockage in the cooling system, where air is trapped in the pipeline and the antifreeze cannot circulate inside, resulting in an increase in water temperature. At this point, all you need to do is bleed the cooling system and vent the air inside. This is like having an air lock in the radiator at home. If you don't deflate the radiator, it will always be cold. Because water cannot circulate, after venting, the pipeline is filled with water and can circulate normally.

         
The method of bleeding the cooling system is very simple. Find the bleeding screw, which is usually located in a prominent position above the water pipe, and it is easy to see. Unscrew the screw to automatically bleed. Adding coolant slowly can reduce the probability of air mixing in the system. Don't add it quickly at first, as it is easy to get air in.
        
Therefore, the work of changing antifreeze is not completed by filling it up. After the liquid level is sufficient, it is necessary to ignite until the water temperature rises to normal and the thermostat can be opened normally. Then, it is necessary to check for any leakage before complete completion. How do I know if the thermostat is on? It depends on whether the fan is running. If the fan is running and the water temperature is not high, it indicates that the thermostat can be opened normally and the water circulation is normal. Finally, check if the antifreeze level is sufficient, and if it is not enough, add it again. Pay special attention not to get burned, and do not easily open the water bottle cover when the cooling system temperature is high and pressure is high.

From: WONDEE Autoparts 2023-8-24