What is antifreeze for? Antifreeze: what is it and is it possible to mix different types with each other

An important role in the operation of the car is played by the coolant. What it is intended for, what it consists of, how often it should be changed and what kind of liquid to choose for a particular model - we will answer these and other questions most frequently asked by our readers in our today's article.

What is coolant for?

The main function of the coolant is to reduce the thermal load on the components and parts of the internal combustion engine installed in the car. It circulates in a closed circuit, in contact with the walls of the engine cylinders (in which the temperature of the combustible fuel reaches several thousand degrees Celsius) through the so-called "cooling jacket" of the power plant (special cavity), heats up and removes excess heat from the cylinder block.

In the engine cooling system, the working fluid flows through two circuits - small and large, periodically heating up (at the working surfaces of the motor) and cooling down (in the radiator). The centrifugal pump is responsible for the circulation of the coolant in the system, and for its redirection from a large circuit to a small one (when the engine warms up), depending on the operating temperature of the engine -.

The expansion tank plays an important role in the engine cooling system: it contains a supply of “coolant”, the excess pressure of the coolant is regulated through its valve, which allows the engine to operate at higher temperatures, preventing it from boiling over.

What is coolant made of?

Two types of liquids are used to cool the engine: distilled water and antifreeze. Water is the cheapest, non-toxic, with the highest specific heat capacity (the ability to absorb heat per unit weight) and the greatest liquid-cooling capacity. Antifreezes are chemically complex substances that have a high boiling point and are not subject to freezing at critically low temperatures (from -40 ° C to -70 ° C).

Distilled water, antifreeze, antifreeze

In the engine cooling system of modern cars, water is not used because of its impracticality: it freezes already at 0 ° C, expanding in volume up to 10% and turning into ice crystals. Accordingly, this “cooler” will no longer be able to perform its main function, removing heat from the engine, in winter, besides, ice crystals formed in the engine cooling system can harm the components and parts of the power unit, leading to the so-called “defrosting » engine - that is, the destruction of cylinder blocks and block heads. Therefore, today the automaker prefers antifreezes that are devoid of the inherent disadvantages of water.

The composition of antifreezes includes two main elements - water and polyhydric alcohols, which have a high ability to expand when heated, one of the key characteristics of the coolant. In addition to water and polyhydric alcohols, antifreezes contain a variety of additives that improve the performance of the coolant: suppressing the formation of rust on metal surfaces, foaming when high temperatures are reached, the destruction of the surfaces of rubber parts, the formation of steam condensate and others. Another element of antifreeze is a dye that plays the role of a marker - if the liquid changes color during operation, then it is time to replace it.

According to the composition of alcohols, all antifreezes are divided into two types: ethylene glycol and propylene glycol.

Ethylene glycol coolants contain ethylene glycol, a polyhydric alcohol with a sweetish odor, yellow in color, whose density at +20°C is 1.112-1.113 g/cm³, the boiling point is 197°C, and the freezing point is -11.5°C. Depending on the operating conditions for which the "cooler" based on ethylene glycol is intended, it is diluted with water in such proportions as 1:1, 1:2 or 2:3. The higher the content of ethylene glycol in such a mixture, the greater the resistance to freezing and boiling it has.

Propylene glycol antifreezes contain propylene glycol, a polyhydric alcohol, which is very similar in chemical properties to ethylene glycol, but has less toxicity and a greater degree of kinematic viscosity. Its last property can be attributed to disadvantages, since when external low temperatures are exposed to the power unit, the circulation rate of such a “cooler” through the engine cooling system drops, and the liquid performs its functions worse.

Antifreezes also differ in the chemical composition of additives - they are divided into four types: traditional, carboxylate, hybrid and lobrid.

Traditional, used mainly in cars manufactured in Europe, North America and a number of Asian countries (Japan, South Korea) until 2000, additives contain corrosion inhibitors from inorganic elements - phosphates, nitrates, borates and so on. They were no longer used for cooling engines for several reasons: a relatively short service life (up to 2 years), low boiling point (up to 105 ° C). In the course of operation, traditional additives, decomposing, covered the working surfaces with a layer of substances contained in them, which led to a deterioration in the cooling of components and parts of the power plant, the destruction of elements of the centrifugal pump, and clogging of the line of the machine's cooling system.

Application: traditional antifreezes (Tosol) are now used in domestically produced cars (VAZ, UAZ, GAZ).

Carboxylate additives containing organic acids (carboxylates) are the most effective in slowing down corrosion. They are able to act pointwise on potential foci of corrosion and cavitation (the formation of steam condensate), covering problem areas with a protective layer of no more than 1 micron, which allows for more efficient cooling of the engine. The service life of such additives is five years or more, depending on the operating conditions.

Application: carboxylate antifreezes are used in cars of Fiat, Ford, KIA, Hyundai, Renault and other brands.
Hybrid additives contain inorganic (silicates, nitrites or phosphates) and organic (carboxylates) substances. The cumulative effect of these mixtures on the centers of corrosion and steam condensate is higher than that of traditional additives, but due to the presence of neolimits, they have the same, but less pronounced, disadvantages as those of "pure" silicate, phosphate and nitrite inhibitors. The service life of hybrid additives is three to five years.

Application: hybrid antifreezes are used in cars of Chrysler, Mercedes-Benz, BMW brands.

Lobrid additives are the newest type of corrosion and steam condensate suppressants, which can be classified as a hybrid subspecies. Their peculiarity is in the distribution in a mixture of organic (90% carboxylates) and inorganic (10% silicates) substances, which leads to an improvement in the technical characteristics of such antifreezes compared to hybrid ones.

Application: used in Peugeot, Citroen, Volkswagen, Skoda, Seat cars.

Marking antifreeze from Volkswagen

The Volkswagen concern has developed its own coolant tolerance marking for carboxylate, hybrid and lobrid antifreezes, which today is used by many anti-freeze manufacturers. So, carboxylate antifreezes are marked G12 and G12 + (correspond to VW TL 774-D / VW TL 774-F specifications), hybrid - G11 (correspond to VW TL 774-C specifications), lobrid - G12 ++, G13 (correspond to VW TL 774- G).

A feature of these specifications is the ban on the use of borates, nitrites, amines, phosphates and silicates in coolants (except for G 11 and G 12 ++, where the content of this substance is allowed up to 680 mg / l and up to 500 mg / l, respectively) . Volkswagen allowed the use of G11 antifreeze in its cars manufactured before 1996, G 12 and G12 + in models manufactured from 1997 to 2008. Antifreeze liquids G12++ and G 13 are used today in the cooling systems of car engines manufactured by the concern since 2008.

Volkswagen carefully monitors that their tolerances are respected by antifreeze manufacturers who label their products in accordance with the G specifications. If at least one of the prohibited substances is included in the coolant marked, for example, G12 +, then such antifreeze does not meet Volkswagen standards and can be considered a fake, since such an “anti-freeze” will not perform all the functions, it can “grow old” prematurely and harm the engine.

What is the difference between antifreeze and antifreeze?

There can be no difference here, since Tosol, familiar to Russian motorists, is the same antifreeze that belongs to traditional coolants. It contains ethylene glycol, water and inorganic additives. Distinguish, for example, "Tosol 40" and "Tosol 65", the first is blue, the second is red. "Tosol 40" is designed for operation at temperatures not lower than -40°С, and "Tosol 65" is designed for operation of non-freezing coolant at temperatures not lower than -65°С.

Can coolants of different compositions be mixed?

As with and, mixing coolants of different types and classes is not recommended due to differences in their chemical compositions. So, when mixing carboxylate and traditional additives, their chemicals can precipitate, which will lead to clogging of the cooling system. Even if this does not happen, then additives of different chemical composition can enter into a reaction, as a result of which their useful properties will be significantly weakened.

Tip: if it is not possible to replenish the supply of “coolant” immediately, it is better to add distilled water to the expansion tank of the cooling system.

How long does it take to change coolant?

Replacement in the cooling system of the working fluid is carried out in three cases: planned, ahead of schedule and in an emergency.

Scheduled replacement of the coolant, depending on the timing established by the vehicle manufacturer. This information can be gleaned from the instruction manuals for each specific model. We repeat: antifreezes with traditional additives are changed every two years, coolants with carboxylate additives - after five to seven years, coolants with hybrid additives - after three to five years, antifreezes with lobrid additives - after five to six years.

After these periods, the performance characteristics of coolants change: they lose their ability to resist corrosion, begin to boil at relatively low temperatures, and remove heat from components and parts of power plants worse.

It is necessary to change the coolant ahead of time if a structural failure of the engine has occurred, for example, exhaust gases have begun to flow into the antifreeze from a leaky cylinder block gasket or when the cooling system is depressurized and air enters it. The interaction of the coolant with exhaust gases or air leads to the fact that the liquid prematurely loses its main operational properties. You can understand that the operation of the cooling system has been disrupted if you notice that the radiator fan has started to turn on more often, deposits similar to jelly have appeared on the walls of the expansion tank, or sediment has appeared in the tank (often found at an air temperature of -15 ° C).

Emergency situations during which the driver had to add water to the cooling system include a burst hose. The hose was changed, the missing amount of “coolant” was supplemented with water taken from the tap. What happens next? Ordinary tap water does not have the properties of distilled water, so the salt content in it is high. These salts, interacting with the chemicals that make up the coolant, form a precipitate that negatively affects the metal parts of the system - in other words, corrosion processes are activated. Precipitated substances impede the circulation of antifreeze in the system, which leads to improper heat removal from engine components, as a result of which the motor may overheat. If you still had to fill the engine cooling system with tap water, then at the first opportunity completely replace the “cooler”, after flushing the system with distilled water.

It is no secret that the cooling system is the most important element of the internal combustion engine, on which the performance of the power unit directly depends. The main function of the system is to remove excess heat generated during the combustion of fuel. Incorrect temperature regime of the internal combustion engine can lead to a reduction in its service life, and severe overheating can lead to complete failure. The cooling system absorbs about 30% of all the energy generated by the engine (the rest is spent on efficient operation or removed through the exhaust system).

What is antifreeze

It is important to monitor the normal functioning of the cooling system for the reason that up to 40% of the malfunctions that occur in the internal combustion engine are somehow connected with a violation of its operation. Efficient heat removal from engine parts is provided by a number of mechanisms working in conjunction. But still, one of the key roles is assigned to the coolant - the liquid circulating in the cooling circuit and in direct contact with the heated surfaces.

The substance poured into the cooling system is called antifreeze. Actually, this term is applicable to liquids used in a wide variety of devices and industries. In this article, we will pay attention to automotive antifreezes designed for use in vehicle power plants.

Requirements for antifreeze

Due to the fact that a very important function is assigned to automobile antifreeze, and its working conditions are quite difficult, strict requirements are imposed on it. The fundamental ones are:

• High heat capacity and thermal conductivity;
• Low freezing point (antifreeze must retain its liquid state even at very low temperatures);
• Low viscosity over a wide temperature range (the fluid must circulate freely through the engine cooling jacket and at the same time provide good heat transfer);
• High boiling point (normal operation at normal engine temperatures);
• Low foaming;
• Good anti-corrosion properties (antifreeze should not contribute to the destruction of engine parts);
• Neutrality to elastomers (compatibility with rubber products);
• Harmless to the environment.

Composition and production technology of automotive antifreeze

The first antifreezes appeared in the 20s of the last century, and, surprisingly, their composition has changed little over the past decades. The vast majority of automotive antifreeze is based on just two components - ethylene glycol (or propylene glycol) and water. They account for 96-97% of the volume of the coolant, and the rest is occupied by additives.

Ethylene glycol, widely used in engineering, is nothing more than a dihydric alcohol, which is a colorless liquid with a density of 1.113 g / cu. see It has a sweetish taste and oily texture. The freezing point of ethylene glycol is -12.9 °С, the boiling point is about 197 °С. This is a toxic substance that, if ingested in a certain amount, can be fatal. Ethylene glycol is aggressive to metals used in a car engine, so it must be used together with anti-corrosion additives.

The main thermophysical properties of water are well known to us. It crystallizes at 0°C and begins to boil at 100°C. Freezing, water increases in volume, and even before reaching the boiling point, it begins to evaporate intensively. Another feature of ordinary water is the tendency to form deposits and scale, which is explained by the presence of salts and minerals in it. All of the above properties plus high corrosiveness do not allow the use of water in its pure form as a coolant. However, it is indispensable as one of the components, especially since soft or medium hard water with a low content of salts prone to precipitation is usually taken to prepare antifreeze.

An interesting point is that when mixing the two main components of antifreeze, a solution is formed with a significantly lower freezing point than that which the original liquids have separately. The exact crystallization temperature depends on the proportion of parts to be joined. As a rule, the proportion of ethylene glycol in antifreeze is 50-60%, which ensures the beginning of the freezing process when the thermometer reads -35 ... -49 ° С.

Another mandatory ingredient in all antifreezes are additives. Despite the fact that their share is quite small (usually about 2.5-3%), it is the composition and quality of additives that largely determine the resulting properties of the coolant, i.e. the efficiency of her work. In other words, superior technology in the production of these important components of antifreeze allows one manufacturer to make a more advanced product than others. The additives themselves are divided into the following groups:

1. Additives based on inorganic compounds - silicates, nitrites, nitrates, phosphates, amines, borates and their derivatives.
2. Additives based on salts of organic acids (carboxylates);
3. Hybrid additives - are made on the basis of carboxylates with the addition of silicates.

Coolants with different types of additives perform their function in different ways, and, first of all, differ in the method of fighting corrosion. The very first antifreezes appeared with additives in the form of inorganic compounds. The corrosion protection mechanism of such compositions is reduced to the fact that the additive package creates a continuous protective layer on the cooled surface, which prevents direct contact with the water-glycol mixture. The layer is formed over the entire area, regardless of the presence of areas of corrosion, thereby interfering with the normal removal of heat. The active components involved in the formation of the layer are quickly consumed due to the large coverage area. As a result, the efficiency of antifreeze is low, and its service life is limited to 2-3 years.

Carboxylate additives have a slightly different mechanism of operation. They affect only the centers of corrosion, while the protective layer created is much thinner than in the case of the first type of additives. Such a selective effect saves active components, which leads to a significant increase in the service life of antifreeze (up to 5-7 years). Another advantage of the local protection mechanism is the high efficiency of heat removal due to the absence of barriers in the "healthy" areas of the metal.

In addition to the so-called corrosion inhibitors, the additive package includes additives with other useful properties. For example, anti-foaming agents, lubricants, anti-scale agents, anti-cavitation components.

Antifreezes based on carboxylates have recently become more widespread. In addition to the advantages already mentioned, they are less prone to deposit formation, provide better seal retention and have a more pronounced anti-cavitation effect.

The manufacturing technology of antifreeze is quite simple and does not require any expensive equipment. At the first stage, the concentrate is prepared, which includes ethylene glycol, additives and a small amount of water (approximate proportions are 92:5:3). The resulting mixture is subjected to multi-stage purification. After this stage, the concentrate is essentially ready to be dispensed into containers and sold. The procedure for diluting it with water is already carried out by the buyer himself. If we are talking about ready-to-use automotive antifreeze, then the enterprise itself undertakes to mix the concentrate and purified water. To obtain strictly defined parameters of the coolant, it is necessary to carefully control the dosage of the initial components.

Antifreeze or antifreeze: the history of the issue

A lot of coolants for engines called "Tosol" are sold on the market. Such a name may mislead some car owners, forcing them to believe that this is some kind of special substance that is different in composition from antifreeze. In fact, the well-known "TOSOL" is a trademark formed by a combination of the abbreviation of the department that developed the liquid ("Organic Synthesis Technology") and the ending "OL", denoting belonging to alcohols in chemistry. The long use of the word "Tosol" has led to the fact that it has become a household name and applicable to the entire category of automotive coolants.

Thus, the words antifreeze and antifreeze denote the same concept, being synonyms. Therefore, it makes no practical sense to pay attention to which of these two names this or that product received. More important are the composition of the additives, the scope and service life. The main criterion for choosing a coolant for a particular car model is the recommendations of the manufacturer of this very car, which are usually based on their own quality standards. We will talk about them below.

Classification systems and quality standards for antifreeze

As with motor oils, international standards such as ASTM or SAE have been developed for automotive antifreeze. However, at present, the specifications issued by the manufacturer of cars and engines are taking precedence. Almost all leading manufacturers not only develop their own quality standards, but also produce antifreezes under their own brand.

In the European market, one of the most authoritative are the specifications of the Volkswagen concern, in accordance with which the widespread division of antifreezes into classes G11, G12, etc. arose. Such markings correspond to well-defined regulations that determine the qualitative and quantitative composition of the additive package. So, the designation G 11 refers to the VW TL 774-C standard, which provides for the use of inorganic additives in antifreezes. Marking G 12 is applicable to coolants with carboxylate additives, defined by the VW TL 774-D specification. There are also classes G12 + and G12 ++, regulated by the VW TL 774-F and VW TL 774-G standards, respectively. And, finally, antifreezes with the most complex and expensive manufacturing technology received the G13 index.

Any of the above Volkswagen specifications excludes the presence of borates, phosphates, amines and nitrites in their respective antifreezes. The concentration of silicates is strictly regulated, and the G12+ class assumes their complete absence.

Examples of standards from leading car manufacturers:

• Ford: WSS-V97B44-D;
• Mercedes-Benz: DBL 7700.30;
• Opel/General Motors: B 040 0240;
• BMW: N 600 69.0;
• Volvo: 128 6083/002;
• Renault-Nissan: 10120 NDS00;
• Toyota: TSK2601G.

Is it possible to mix antifreezes and what does color affect?

The question of antifreeze compatibility usually arises from car owners who have purchased a used car and are not able to determine the brand of liquid poured into the cooling system. Moreover, motorists who are not versed in technical subtleties in the course of solving this problem, first of all, take into account the color of the composition splashing in the expansion tank. And, indeed, manufacturers use dyes with a variety of shades to color coolants. The most popular colors: red, green, blue, yellow, purple, orange. Some standards even regulate the use of certain shades. However, in fact, color is perhaps the last criterion that should be considered when mixing different brands of antifreeze. Dyes introduced into antifreeze are used only to make it clear that the liquid is technical, and, therefore, can threaten human health. In addition, due to the acquired shade, the visibility of antifreeze (initially colorless liquid) in the same reservoir of the cooling system improves. There is no direct connection between the color and the properties of the coolant.

What considerations should be followed when mixing antifreezes? Here are at least a couple of tips:

1. Without problems, you can combine antifreezes that have the same base and meet generally recognized quality standards. True, the composition of the liquid is often not published by the manufacturer, so it remains only to follow the recommendations indicated on the label.
2. Different types of antifreezes (with inorganic and organic additives) may be mixed only if the manufacturer explicitly indicates this possibility.

The incompatibility of antifreezes lies in the likelihood of a reaction between their constituent additives. This is fraught with sedimentation or deterioration of performance, which may affect the operation of the engine.

To begin with, the function of the coolant in internal combustion engines is performed by special compounds known among motorists under the name. The use of distilled water in cooling systems has long been abandoned, since water freezes at low temperatures, causes increased corrosion of channels in and, causes scale formation, etc.

Today, various TOSOLs or antifreezes can be available in two versions:

• in the form of a concentrate, which must be further diluted with distilled water in specified proportions;
• a ready-to-use product that can be immediately poured into the cooling system without additional manipulations;

In any case, the engine coolant not only protects the engine from and does not freeze in winter (unlike water), but also prevents active corrosion processes from starting in the liquid cooling system of the internal combustion engine, keeps the channels clean, and extends the life of individual elements (, etc.). e.)

It is important to take into account that antifreezes are different in composition, and also lose and change their properties during operation. This means that they cannot be mixed freely. Also, the liquid has a strictly limited service life, that is, it is necessary to periodically replace antifreeze or antifreeze, as well as regularly monitor the condition of the coolant.

Read in this article

Car engine coolant: general information

It is well known that an internal combustion engine is a heat engine that converts the energy of burning fuel into mechanical work. Naturally, such an installation must be cooled in order to maintain the required thermal regime.

In other words, for the normal operation of all components and parts under loads, the heating of the motor must remain within strictly specified limits. The operating temperature of the engine should neither fall below the specified threshold nor exceed the calculated value.

To solve the problem on cars, it is used, which is a combination of air and liquid cooling of the internal combustion engine. The fluid system involves forced circulation of the working fluid.

On a running engine, coolant heating can reach up to 100 degrees Celsius and even higher, while after stopping the engine, the liquid cools down to outside temperature during a long idle period.

As you can see, the working fluid is in rather difficult conditions. At the same time, special requirements are put forward for it. The fact is that the properties of the liquid should, first of all, ensure maximum efficiency of the engine cooling system. It directly depends on this. The coolant must have high thermal conductivity and heat capacity, have a high boiling temperature threshold, and sufficient fluidity.

Moreover, after cooling, such a liquid should not greatly expand in volume and crystallize (turn into ice). In parallel with this, the liquid should also not foam during operation, and also not be aggressive, that is, cause corrosion of various metal elements, affect rubber pipes, seals, etc.

Unfortunately, although distilled or purified water is cheap to produce and has a number of necessary properties (it has a high ability for efficient cooling, has a high heat capacity, non-combustible, etc.), it is still problematic to use it in an engine.

First of all, it has a low boiling point, evaporates quickly, and various impurities in its composition (salts, etc.) cause active scale formation. Also when the outside temperature drops to zero degrees and then ice forms.

In this case, a significant increase in the volume of frozen water occurs, which causes ruptures of channels and pipes, that is, damage occurs, cracks appear in metal parts, etc. For this reason, water cannot be used year-round in regions where average daily temperatures drop to zero or below in winter.

It is quite obvious that it is very difficult to constantly drain the water from the cooling system before parking the car on the street or in an unheated room. To solve the problem, special coolants have been developed that have acquired the property not to freeze at low temperatures.

In fact, the name "antifreeze" itself comes from the English "antifreeze", that is, non-freezing. These compositions quickly displaced water from liquid cooling systems, thereby greatly simplifying the features of vehicle operation.

As for TOSOL, this development is an analogue of Western antifreeze, only it was developed on the territory of the former USSR. The specified type of coolant was originally created for VAZ cars, while the trademark was not registered.

Today, many manufacturers of coolants in the CIS use the well-known name TOSOL for their products, however, the performance properties of liquids may differ due to the presence of various additives and additional components.

Features of antifreeze and practical operation

Note that in the engines of modern cars, antifreeze fluids are most often used, which are based on a glycol base. Simply put, such an antifreeze liquid is a mixture of water and ethylene glycol. There are also coolants that use propylene glycol, while mixing ethylene glycol coolants with propylene glycol is not recommended.

In practice, ethylene glycol or monoethylene glycol is a yellowish oily liquid. The liquid is odorless, has a slight viscosity, has an average density and a boiling point of about 200 degrees Celsius. At the same time, the crystallization (freezing) temperature is slightly less than -12 degrees.

If ethylene glycol or a solution of ethylene glycol with water is heated, a significant expansion occurs. To prevent the system from “breaking” from excess pressure, it was added to the device, which has the marks “min” and “max”. According to them, the required coolant level is determined.

It is also important to consider that ethylene glycol and its solutions are very aggressive, capable of causing severe corrosion of parts made of steel, aluminum, cast iron, copper or brass. In parallel with this, there is an increased toxicity of ethylene glycol and its extremely negative impact on living organisms. In other words, it is a strong and dangerous poison!

As for propylene glycols, they have similar properties to ethylene glycols, but are not as toxic. However, propylene glycol is much more expensive to produce, resulting in a much higher end cost. Also, at low temperatures, propylene glycol becomes more viscous, its fluidity is worse.

For the above reasons, the composition of the coolant necessarily uses a whole package of active additional additives that provide anti-corrosion, protective and detergent properties, prevent foaming, stabilize the liquid, tint the solution, give a characteristic recognizable smell, etc. Also, additives somewhat reduce toxicity.

Let's get back to using antifreeze. The need to mix ethylene glycol or propylene glycol with distilled water is dictated by the fact that the freezing point of such a solution directly depends on the proportions of these two components.

In simple words, water freezes at zero, ethylene glycol at -12, but mixing them in different proportions allows you to create solutions whose freezing threshold is from 0 to -70 degrees and even higher. The ratio of glycol to water also affects the boiling point of the solution.

Without going into details, in practice, the lowest freezing point can be achieved if the composition contains just under 67% ethylene glycol, which is diluted with 33% water. In this case, the same or very close freezing point can be obtained at different ratios of water and concentrate.

As for practical operation, as a rule, motorists often use a simple scheme when replacing coolant in many regions, diluting the antifreeze concentrate with water in proportions of 60/40. Please note that this is a general guide, before preparing the solution, read the individual recommendations of a particular antifreeze manufacturer on the package.

To check the ratio of ethylene glycol and water in the solution, the density is additionally measured. For this, a hydrometer is most often used. Based on the data obtained, we can conclude what is the content of ethylene glycol and determine the crystallization temperature.

Mixing antifreeze and antifreeze

It should be noted that the compatibility of various coolants depends on the technical conditions of their manufacture. In simple terms, fluids may be completely incompatible or only partially compatible.

The fact is that each manufacturer uses different additives that can react, thereby the mixture loses the necessary properties, precipitation occurs and a number of other undesirable consequences occur.

Taking into account the fact that during operation it periodically becomes necessary to raise the coolant level in the expansion tank (the water in the composition boils away over time), it is more correct to add distilled water or use only the brand and type of antifreeze that was previously used.

If an emergency malfunction occurred, then it is optimal or completely to drain the existing residues, flush the system and fill in fresh coolant in full, or add antifreeze that is suitable in color and properties.

As for norms and standards, as a rule, domestic TOSOLs must comply with the requirements of GOST, while they are not separately certified. Imported antifreezes are standardized according to SAE and ASTM.

Foreign standards define various properties of liquids based on ethylene or propylene glycol, determining the purpose, adjusted for operating conditions. Liquids are divided into compositions for passenger cars, small trucks, heavy vehicles, special equipment, etc. Note that antifreezes according to ASTM type D 3306 are allowed for use on domestic passenger cars.

You should also take into account the individual specifications of the automakers themselves, who often put forward a number of their own requirements. In the list of various regulations of large concerns, it should be noted that the use of antifreezes is prohibited or highly discouraged, in which the presence of various corrosion inhibitors, including nitrites, phosphates, etc., is noted.

At the same time, the maximum content of silicates, chlorides and other components in the coolant is also determined. Following these guidelines allows you to extend the life of the seals, avoid active scale formation, and increase the level of protection against corrosion.

When and why you need to replace antifreeze

As already mentioned, antifreezes can have a negative effect on the parts of the cooling system and the engine itself. To reduce the degree of this effect, various additives are used. However, during operation, these additives “wear out”, that is, the content of additives and their efficiency is reduced.

Simply put, over time, corrosion processes become more active, the coolant begins to foam more strongly, the heat dissipation deteriorates, and the temperature regime is disturbed during the operation of the internal combustion engine. For this reason, antifreezes are recommended to be changed after 2 years, or every 50-60 thousand km. mileage (whichever comes first).

As for modern developments such as G12 and G12 + antifreezes, the service life of these fluids has been extended to 3-4 years, but their higher cost can be considered a minus.

Also, the engine coolant needs to be replaced in cases where exhaust gases from the cylinders have entered the cooling system or traces of engine oil are visible in the antifreeze / antifreeze. As a rule, the cause of such malfunctions is a broken cylinder head gasket, cracks in the BC or cylinder head. In any case, the coolant under such conditions will quickly lose its useful properties.

The following signs indicate the need to replace the coolant:

• appearance in the expansion tank;
• change in the color of the coolant, the appearance of a burnt smell;
• with a slight decrease in the outside temperature, a precipitate is visible in the tank, the antifreeze becomes jelly-like, etc.
• , the cooling system fan is constantly running, the motor is on the verge of overheating;
• antifreeze has acquired a brownish-brown color, has become cloudy. This indicates that the liquid has exhausted its resource, the additives do not perform their function, and active corrosion of elements and parts occurs inside the cooling system.

We also note that in the event of an emergency, it is often necessary to add to the antifreeze either coolant from another manufacturer, distilled water of dubious quality, or ordinary running water. In such cases, it is necessary to get to the place of repair, carry out all the work, and then without fail flush the cooling system and only then completely replace the antifreeze.

1. As for the process itself, you only need to change the coolant on a cold engine. After the engine has cooled down, you need to unscrew the cap of the expansion tank or the radiator cap.
2. Next, you need to open the valve of the radiator of the interior heater (stove radiator). This is necessary in order to remove possible fluid residues in the radiator and pipes to it.
3. Then you should unscrew the drain plugs in the radiator of the car's cooling system, as well as the plug in the cylinder block.
4. After that, the coolant is drained into a pre-prepared container, after which the plugs can be tightened.

Please note that when working with coolants, it is important to understand that ethylene glycol is a strong poison, and can also enter the body even through the skin. A small dose of ethylene glycol when taken orally is enough for severe poisoning and death!

Also, ethylene glycol has a sweetish aftertaste, it must be kept out of the reach of children. It is forbidden to spill ethylene glycol or propylene glycol, as the liquid is dangerous for animals. It is forbidden to pour antifreeze into water bodies, pour it onto the ground or down the drain!

1. The final step is to fill the expansion tank with fresh fluid. Fill the coolant slowly and carefully to avoid the formation of air pockets in the system.
2. At the end of the procedure, the tank and / or radiator cap is screwed on, then the engine can be started. After starting, the unit warms up at XX to operating temperature (on many cars until the fan turns on).
3. Now the engine must be stopped and allowed to cool, after which the reservoir cap is opened again and the coolant is added according to the level (in case of a decrease).

If we talk about flushing the cooling system and radiator, during scheduled regular replacements of antifreeze of the same brand / type, then it will be enough to flush the entire system with ordinary distilled water. In extreme cases, you can boil running water in advance, and then use it for washing.

In cases where a transition is made from TOSOL to antifreeze, from water to TOSOL, from antifreeze of one color to another type of coolant, or the dirty antifreeze, etc., simply changes, then the system needs to be cleaned more thoroughly. This means that it will be necessary to separately remove possible or obvious deposits, scale, rust, decomposition products of additives in old antifreeze, etc.

As a rule, special ready-made cleaners of the engine cooling system are used for cleaning. Such compositions are complex, have corrosion inhibitors, well remove scale and deposits. Also, motorists use various water-acid solutions of self-preparation for flushing, however, the use of such solutions is not recommended on modern internal combustion engines.

The general procedure for flushing the cooling system is as follows:

• after draining the coolant from the system, the flushing liquid is filled. Then the engine is started, after which the unit runs for a certain amount of time (usually 20-40 minutes).
• Next, the washing is drained, assessing the degree of contamination of the drained liquid. The procedure is repeated until the outflowing flush is clean.
• At the end, distilled water is poured into the system, the engine warms up again to operating temperatures, then the water is drained. This is necessary to remove wash residues. Then you can fill in fresh antifreeze without the risk of losing its properties as a result of contact with flush residues.
• We also note that although it is possible to wash the remains of the cleaner in the cooling system at one time, experienced drivers recommend flushing the system at least twice with distilled water.

During operation, the level of antifreeze in the expansion tank decreases even when the system is tight. The problem is that water is evaporating. Distilled water should be added to the tank (in extreme cases, ordinary and well-boiled water for at least 30-40 minutes).

If there is an antifreeze leak, then it is no longer possible to compensate for the loss with water alone. In other words, it is necessary to add coolant, and taking into account the fact that many coolants do not mix with each other.

It is optimal to have a concentrate and distilled water in stock for topping up, mixing the liquids in the proportion specified by the manufacturer. As for ready-made antifreezes, try to avoid purchasing such compounds in car markets or from individuals who sell similar products along highways.

There have been frequent cases when, instead of coolant, tinted running water, antifreeze treatment, etc. were sold. For this reason, the right decision would be to buy coolant in specialized car dealerships.

We also note that it is forbidden to use pure concentrate undiluted with water in the engine cooling system. As already mentioned, ethylene glycol with a package of additives freezes at negative temperatures of about -12 degrees.

It turns out that the concentrate will simply freeze in the system, since without dilution with water it cannot be considered a ready-to-use product. As for the proportions, you need to study the label on the package with the concentrate. Usually, manufacturers themselves indicate separately what to pour into the radiator or tank on different cars, how much concentrate and water is needed, and how to mix them in order to get the desired freezing temperature of the coolant.

In parallel, we note that cases of fake antifreezes of well-known brands have become more frequent in the CIS. For this reason, carefully inspect the canister. The container must be of high quality, all stickers and labels must have a clear font and be placed evenly on the canister.

The canister should indicate the batch number, manufacturer, as well as recommendations on how to properly dilute the antifreeze (in the case of a concentrate) or use a ready-made product. The boiling point, freezing point, date of manufacture, expiration date and other important information are also indicated.

Cork deserves special attention. Typically, manufacturers use caps with a disposable seal. Additionally, for better protection against counterfeiting, a hologram sticker, etc. may be present.

It is necessary to verify the integrity of the seal, the toothed ring should fit snugly against the neck, not scroll. The lid itself should not be glued to the neck. Also, the canister must be airtight, no liquid leaks or air can escape from under the lid when turned over or pressed.

Finally, we note that many manufacturers use containers made of transparent or translucent plastic, allowing you to assess the color and condition of the liquid in the canister. When shaking the coolant canister, foam should form, which settles in a couple of seconds in a canister with liquid ready for use, and also after 4-5 seconds. in the case of undiluted concentrate.

If during the inspection it is noticed that the liquid has become cloudy, the foaming is high, the sediment at the bottom is visible, or the general color of the antifreeze is suspicious, then it is better to refrain from such a purchase.

In this article we will tell you what automotive antifreeze is, how it differs from antifreeze and what is the service life. Effect on engine overheating.

What is the difference?

Antifreeze- the name of the antifreeze developed for VAZ cars. The Tosol trademark has not been registered, so it is used by many domestic manufacturers of coolants. The name arose like this: the first 3 letters were taken from the name of the department where it was made: “Technology of Organic Synthesis”. And the ending "ol" came from the chemical industry and indicates that the products belong to alcohols.

As a result, "TOSOL" appeared, which was intended for the first Zhiguli cars. Over time, the name from the abbreviation ("TOSOL") turned into a household name - this is how motorists began to call any coolants. Do not succumb to the delusion that antifreeze is intended for Russian cars, and antifreeze for foreign cars. Antifreeze is one of the antifreezes.

What are they made of?

antifreeze- coolants of the car cooling system that do not freeze at low temperatures. They consist of dihydric alcohol - ethylene glycol (65%), water (35%) and anti-corrosion additives, which chemists call inhibitors - corrosion retarders. Manufacturers give them their own names ("Tosol", "Lena") or indicate the freezing point (OJ-40).

The basis is a glycol-water mixture, on which they depend: the ability of antifreeze not to freeze at low temperatures, its specific heat capacity, viscosity and effect on rubber. The most common antifreeze based on ethylene glycol. But its aqueous solution is aggressive to the materials of the cooling system parts (steel, cast iron, aluminum, copper, brass, solder).

Therefore, a complex of additives is added to the coolant: anticorrosive (inhibitors), antifoaming and stabilizing.

There are many standards: in Russia it is GOST 28084-89 (which is obsolete), in the USA - ASTM D3306, D4340, D4656 (constantly updated), in England - BS 6580. They determine the characteristics of antifreezes: density, crystallization onset temperature, corrosive effect on metals, impact on rubber, resistance to hard water - and regulate tests for their verification. But they do not specify the composition and concentration of additives, as well as the miscibility of liquids. This, as well as the color of antifreeze (blue or yellow), is chosen by the manufacturer.

There are no GOSTs regulating the service life of antifreeze and the conditions for resource tests. In practice, manufacturers use technical specifications (TS), entering the necessary information into them. Therefore, antifreezes often appear in stores, freezing at -25 ° C and boiling at 90 ° C. Officially, the boiling point of antifreeze should be in the range of 105-115 ° C.

In addition to general standards, many manufacturers apply specifications with additional requirements. For example, the Volkswagen Group's regulatory system, which standardizes antifreezes labeled G11, G12 and G13. Many chemical companies and trade representatives began to use their compact names to classify coolant.

What is the service life?

During operation, antifreeze ages - the concentration of inhibitors gradually decreases, heat transfer decreases, the tendency to foaming increases, and unprotected metals corrode intensively. The resource depends on the quality of antifreeze and the mileage of the car.

The replacement period is prescribed by the car factory or manufacturer. Usually change every 2-3 years. On modern machines, they change during operation for more than 5 years or 250,000 kilometers. For example, Volkswagen adheres to such a schedule for new cars. AvtoVAZ indicates a change after 75,000 km or 3 years, when using such antifreeze. Next, we list the signs when the coolant is aging earlier:

• a jelly-like mass is formed on the inside of the neck of the expansion tank, at slight negative temperatures (minus 10-15 ° C), clouding is noticeable in it (like a light cloud), a precipitate forms, and the radiator electric fan also works more often. When at least one of these signs appears, the antifreeze should be changed as soon as possible;
• the color becomes reddish-brown. This means that the parts of the system are already corroding. Such fluid must be replaced immediately, regardless of how long it has served.

Can you mix?

Domestic liquids produced by different manufacturers according to the same specifications can be mixed. If the specification numbers are not the same, antifreezes are often incompatible. The components of additive complexes can react with each other and lose their useful properties. Therefore, in a hopeless situation, it is better to add water, and then replace all the fluid in the system.

If the color is different. For example, the old one is yellow, but you are going to fill in red antifreeze. Can you mix? Read more in this article.

Effect on engine overheating

Boiling point of antifreeze - not less than 105°С if it complies with all standards and GOSTs. It happens that manufacturers try to save on products and instead of expensive ethylene glycol they add cheaper glycerin, which costs a penny. Glycerin-based antifreeze becomes viscous, as a result, the motor overheats.

So that it does not freeze at -25 ° C, manufacturers add methanol, which significantly reduces the freezing point. The boiling point of methanol is only 65.5°C. At higher temperatures, methanol begins to actively evaporate and reduces the boiling point of antifreeze to 85-90°C instead of the prescribed 105-108°C.

Leaks of low-quality antifreeze lead not only to overheating of the engine, but also to a fire. Get methanol, for example, on a hot collector - open burning may occur.

Not always, the addition of glycerin to the composition indicates low-quality antifreeze. For example, Volkswagen, in the production of G13 coolants, adds a small percentage (up to 20% in concentrate) of glycerin to the composition. This is done not for the sake of economy, but thanks to the environment. Glycerin is a by-product in the production of biodiesel, which means it needs to be put somewhere - for example, used in antifreeze.

We advise you to purchase antifreeze at branded points of sale or through official suppliers in online stores. If you bought a fake, then in winter it will lead to a poor start of the engine in cold weather, and in summer - to a fire in the engine compartment.

Engine coolant, or antifreeze, is a special fluid that runs through the engine to keep it within its correct operating temperature range. It is made from ethylene glycol or propylene. As a rule, it is green, blue or even pink. However, antifreeze is not limited to temperature control. Maintaining the correct level of this fluid also helps prevent corrosion.

Traditionally, the combination of antifreeze and water is known as "coolant".

Unlike air-cooled vehicles, which rely on a fan to blow over engine components, water-cooled engines use a radiator, water pump, thermostat, heater core, hoses, and passages within the engine.

Why do you need antifreeze

Without coolant, the heat generated by constant internal combustion will destroy the engine very quickly. Water alone is not enough to keep the system cool. High temperatures inside the engine can cause it to "boil" because after a while the water in the system will completely evaporate.

Likewise, in very cold weather, the water freezes when the vehicle is idle, rendering such a cooling system useless.

How the cooling system works

Your car's engine generates a lot of heat during operation and must be constantly cooled to avoid damage. The cooling system in your car works by supplying coolant through channels in the engine block and head. As the coolant flows through these channels, it picks up heat from the engine. The fluid then travels through a rubber hose to the radiator at the front of the car. Once the fluid has cooled, it is returned to the engine to repeat the cycle. And a special pump keeps fluid flowing through the entire system.

For more information about the engine cooling system, see this video:

What is the service life of antifreeze

Speaking about the service life, you need to be very careful. When the term "coolant" is used, it can mean several things. Coolant, consisting of antifreeze solutions and water from a 50 to 50 household tap, will last about 3 years. A coolant that consists of antifreeze and distilled (deionized) water (a 50/50 solution) should last about 5 years. It is best to focus on the instructions that will be on your package.

If you live in a region that is exposed to very cold temperatures, consider changing your coolant at the start of winter as a sort of insurance policy. The admixture of antifreeze should be no more than 50%, since any more antifreeze will increase the freezing point. Note that a 50% antifreeze mixture will give resistance to temperatures down to -30C, while 60% antifreeze in the mixture lowers this threshold to -20C.

Types of antifreeze

Coolants are produced in many countries around the world. Each country has its own standard. Moreover, many national standards are already outdated today.

Here are some of them:

• GOST 28084-89 - RF,
• BS 6580: 1992 - UK,
• SAE J 1034 and ASTM D 3306 - USA,
• AFNOR NF R15-601 - France,
• JIS K2234 - Japan.

Many national standards create a number of difficulties for manufacturers of antifreezes. Especially if they are exporting their products.

The modern separation of coolants occurs according to the composition of anti-corrosion additives as follows:

1. Traditional (Antifreeze and its modifications, corrosion inhibitors - inorganic substances, service life 1-2 years, withstands temperatures up to 108 degrees Celsius),
2. Hybrid (marking G11, contains both organic and inorganic inhibitor, service life 3 years),
3. Carboxylate (marking G12, contains an organic acid-based corrosion inhibitor, service life is about 5 years),
4. Lobrid (marking G12 ++, the composition includes a small part of mineral inhibitors, in combination with an organic base),
5. G13 (it contains propylene glycol instead of ethylene glycol. The most expensive representative of antifreezes. However, it is considered the least toxic and its service life is not limited if the liquid is poured into a new car).

For those who want to dive deeper into the types of antifreezes, we leave a special video:

The difference between antifreeze and antifreeze

This is a question that can be found very often on the Internet. In fact, the answer is very simple. There is no difference between antifreeze and antifreeze. Antifreeze is just a type of antifreeze. The fact is that in the Soviet Union this was the name of the coolant. And even earlier, water was poured and diluted with ethylene glycol to prevent freezing at sub-zero temperatures. But this liquid turned out to be too viscous. In addition, it gave too strong corrosion of the metal. That is why a new coolant called antifreeze was created. TOS stands for Organic Synthesis Technology.

The word "antifreeze" in translation into Russian - "non-freezing". All antifreezes consist of two basic components - water and ethylene glycol. Plus various additives. This is the modern name for coolants for cars. There are no differences between antifreeze and antifreeze, this is a myth.

You can find more information on this subject in this video:

Color classification of antifreezes

No less rare on the Internet you can find the question: how does red antifreeze differ from, say, green? Which to choose?

In fact, everything is very simple. Initially, antifreeze is colorless. Dye is added to it by manufacturers to improve the visibility of the liquid level in the expansion tank. Different coolants by type have different colors, and certain ones.

For example,

• Traditional antifreeze (antifreeze) is usually blue.
• Hybrid (G11) usually green.
• Carboxylate (G12) - red or pink.

Thus, the color of antifreeze is just an accompanying parameter by which its classification can be determined. And the choice of liquid must already be made based on it. In addition, antifreezes of the same color may differ in both property and quality.

How to choose

Antifreeze can be bought either ready for use or in the form of a concentrate (it will need to be diluted with distilled water in accordance with the proportions indicated on the label). Otherwise, you should focus on the type and brand of the manufacturer.

Of course, the most modern antifreezes are 12 and 13 series.

But the main advice is to focus on what is recommended and filled in by the manufacturer.

In addition, if you doubt the originality of the purchased liquid, check it for acidity. Add some baking soda to a small amount of liquid. If the reaction does not go, such a liquid can be safely poured into the engine.

Is it possible to mix antifreezes of different colors

It is undesirable to mix antifreezes of different brands and types, since they have different sets of additives, and they can interact with each other, precipitating and worsening the anti-corrosion functions of the liquid.

It is important to know that in some individual cases, mixing additives leads to increased corrosion.

Features of the use of antifreeze. Coolant replacement

Before replacing antifreeze, the cooling system must be flushed. This is necessary to get rid of old coolant residue and avoid mixing. You can flush the system either with special additives or with distilled water.

It is important to remember that after flushing, up to 2 liters of water remain in the system. Keep this in mind when diluting the concentrate.

What to do if you find an antifreeze leak

If you find that there is less coolant in the system, then first of all you need to check for leaks in the hoses, examine them carefully. Antifreeze can leak due to cracks, poor connections, and breaks. This malfunction can also be detected in the form of smudges on the floor mats.

You can also look for a leak in the radiator area, near the pump. Be sure to check the tank lid, especially the sealing rubber, how well it fits.

Check both on a hot and cold engine. See if there are drops or fluid leaks.

The most unpleasant reason why antifreeze can go away is the internal depressurization of the cooling system.

If the leak cannot be detected, then with a high degree of probability you have a broken engine head gasket. Try to remember if your motor has overheated lately, if it works intermittently. With such a malfunction, the antifreeze goes into the cylinders and burns along with the fuel. This is an additional sign of a broken gasket.

For more information about possible causes and solutions to problems, see the video:

Why You Shouldn't Add Antifreeze

You open the hood and find that there is less coolant in the expansion tank. The first thought is to add liquid. However, you need to be extremely careful here.

If you don’t know which antifreeze was originally filled in, then when a new one is added, mixing may occur, the consequences of which we talked about a little earlier.

In order not to change the coolant completely, you can simply top up with plain distilled water, this is safe.

And finally, we have prepared for you a very interesting video on the topic of coolants! Experiments with antifreeze: