Antifreeze is a liquid that does not freeze at low temperatures and is used for cooling systems of internal combustion engines. Antifreeze consists of a mixture of propylene glycol, glycerin, ethylene glycol and other chemical compounds with water, as well as dyes and anti-corrosion additives.
According to the type of anticorrosive substances, coolants are divided into carboxylate and silicate. The carboxylate antifreeze contains special corrosion inhibitors that are based on organic acids. Corrosion inhibitors are adsorbed only in the places of its occurrence, where they form protective layers. Silicate antifreeze during operation of the cooling system covers all its internal surfaces with a thin layer of scale, which in some way impairs heat transfer and ultimately reduces engine cooling.
For the smooth operation of the car, timely replacement of antifreeze is extremely important. Between its replacements, the duration of engine operation depends on several factors, in particular on the presence of special anti-corrosion additives in the antifreeze. As long as these substances are available in the required quantity, replacement of antifreeze is not required. With their reduced concentration or absence, the engine cooling system is not protected from electrolyte corrosion.
Replace antifreeze if necessary. The car is made independently. It is necessary to take into account that it is toxic and the following safety measures must be observed: well-ventilated rooms are selected, antifreeze does not merge near water supply points (water intake stations, wells, columns) and into open water bodies, work is performed on a cold engine.
The car is placed forward down on a hill or overpass, so that most of the liquid flows out. Under the radiator there is a capacious container for draining the liquid. Then the radiator cap opens and the drain plug on the cylinder block wall, which is located next to the oil filter , is unscrewed . Spent old antifreeze flows out of the radiator and expansion tank. After the spent antifreeze merges, the hoses and pipes of the cooling system are inspected for the presence of tears and cracks; if defects are found, they are replaced.
After that, the cooling system is washed out from rust and various deposits. For this, a drain plug is screwed on the cylinder block. Distilled water or a special flushing fluid is poured into the cooling system through the radiator neck. After the radiator cap is screwed, the car starts, the stove is switched on to maximum mode and the engine is left to idle until it is completely warmed up. After the engine is turned off and completely cooled, the drain plug and radiator cap are unscrewed and the flushing fluid is drained into a suitable container. This procedure is performed several times, depending on the color and quality of the washing liquid after washing.
After that, a new antifreeze is poured according to the recommendation for a specific car model. In this case, the machine is placed forward up on a hill or overpass to avoid air congestion in the cooling system. The antifreeze is not completely filled, the engine starts with the radiator cap open, and the stove is switched on to the maximum mode. Thus, air bubbles that remain in the engine cooling system are pushed out. The antifreeze is then added to the required level, the radiator cap is screwed. But this is not the end of antifreeze replacement . After several trips by car, it is necessary to check the level of antifreeze in the cooling system and add it, if necessary, to the required level in the expansion barrel.