How often to change antifreeze: increasing engine life. Replacing the coolant: how to change antifreeze correctly

What are antifreezes?

Today, most antifreezes are made on the basis of ethylene glycol and are divided into three classes G11 - G13. In the USSR, a liquid called “Tosol” was used as a cooling solution.

Recently, liquids based on propylene glycol have appeared. These are more expensive antifreezes, as they have higher performance properties.

Of course, the most important property of the cooling solution is its ability not to freeze at low temperatures, but this is not its only function; another equally important function is to lubricate the cooling system components and prevent their corrosion.

Namely, to perform the functions of lubrication and prevent corrosion, antifreeze contains a wide range of additives that do not have an eternal service life.

And in order for cooling solutions not to lose these properties, these solutions must be changed periodically.

Precautions and Tips

When replacing antifreeze, the following recommendations and warnings will help you:

• When deciding how much antifreeze you need, keep in mind that the liquid level in the radiator must reach the lower edge of the neck (if coolant is poured into it).
• When working with antifreeze, be extremely careful and fill it away from children. It is advisable to do everything in the fresh air to inhale as little ethylene glycol vapor as possible.
• If liquid gets into an open area of ​​the body, into the eyes or other mucous membranes, immediately wash the area with clean water.
• Do not allow antifreeze splashes to get on the painted parts of the car body. Especially if you use a liquid with added silicates or based on aggressive ethylene glycol. If coolant gets in, it can corrode the paint, so if this happens, wash the surface with plenty of water.
• The toxic components of the liquid are dangerous to the lives of people and animals, so always close the container with the composition.
• If you use the same antifreeze from the same manufacturer, then flushing the cooling system is not necessary. This procedure is only important when switching to a different type of coolant.
• If you are using a concentrate rather than a ready-made liquid, remember the proportions. In summer, you can add more water to the composition (1:1), since in the heat it will evaporate faster. In winter, you cannot add so much water, as under the influence of low temperatures this will lead to freezing of the liquid. As a result, the expansion tank may burst.

Purpose of antifreeze

Antifreeze is the general name for special fluids used in the engine cooling system. As it circulates through the cooling system, the coolant absorbs heat and transfers it to the radiator, from where excess heat escapes. All modern antifreezes are a mixture of water and ethylene glycol. Due to the presence of ethylene glycol, the coolant has a high heat capacity and does not freeze at temperatures down to -60 degrees Celsius. Antifreeze also contains lubricating and anti-corrosion additives.

It is worth noting that antifreeze is still the same antifreeze. The name "TOSOL" refers to a brand of antifreeze in the USSR.

DIY antifreeze replacement instructions

The coolant replacement algorithm is as follows:

1. We put the car on a lift or inspection hole.
2. Remove the lid and drain the coolant into a pre-prepared container. The location of the cover depends on the make and model of the machine. In most cases, the drain cap is located on the expansion tank, or in one of the lower corners of the radiator. In some cases, it is necessary to disconnect the lower radiator hose.
3. To completely drain the antifreeze, screw on the drain cap of the tank, turn on the heater to maximum and start the engine for two minutes. Then drain off the remaining liquid.
4. Pour antifreeze into the expansion tank.
5. We start the engine and let it run for 15-20 minutes.
6. We check the marks on the tank. The antifreeze level should be above o.

At this point, the coolant replacement procedure is completed.

How to choose coolant for a car?

When choosing a coolant, you should find out which one is suitable for your car. Antifreeze is an aggressive liquid that actively reacts with various types of metals. Some types of coolant are incompatible with copper and brass radiators, while others cause corrosion of aluminum parts. Please refer to your owner's manual or your authorized dealer for exact specifications.

There are three main classes of antifreeze:

1. G11 - ethylene glycol coolant with a small addition of anti-corrosion additives and carboxylic acid. They are the cheapest and most short-lived type of antifreeze. This class is assigned the color green. It is worth noting that domestic antifreeze conditionally belongs to this group. The designations G11+ and G11++ indicate increased carboxylic acid content.
2. G12 - coolant based on ethylene glycol with organic additives and a high content of carboxylate compounds. This class of antifreeze copes much better with pockets of corrosion. Due to its high heat capacity, this liquid copes much better with cooling powerful engines. Such antifreeze is more expensive, but will also last much longer. This class is assigned the color red. The designations G12+ and G12++ indicate the presence of silicate additives or their analogues.
3. G13 - coolant based on an environmentally friendly analogue of ethylene glycol - polypropylene glycol. It is non-toxic and decomposes much faster. In terms of its properties, this class of antifreeze is no different from the classes G12+ and G12++. However, it costs an order of magnitude more. This class is assigned the color purple.

It is worth noting that the division into colors is conditional. Color has nothing to do with the chemical composition and depends solely on the whim of the manufacturer or the decision of marketers. Manufacturers may paint the same antifreeze in different colors to differentiate them by brand.

How to pour antifreeze into the cooling system: opinions of car owners

Concentrate and point

“It is best and most profitable to purchase pure concentrate, not counterfeit and without temperature restrictions (for example, from VAG). Drain off excess distillate based on the volume of your car's cooling system. Pour in the concentrated composition, checking the density of the liquid and adjusting it if necessary.

It is important not to lower the temperature below -50 degrees, otherwise this will affect heat transfer, and it will be harder for the engine to work in the summer. The optimal temperature range is from -40 to -50 degrees.

Alternatively, pour the finished composition at -50 degrees

The remaining water in the system will bring the temperature to the optimal value. But it all depends on the specific engine - will it be possible to drain a large volume from it?”

Face up and forward

“Raise the front of your car as high as possible. Thanks to this, the air will leave the system very quickly. Next, fill the expansion tank with antifreeze to the level between the marks, then completely fill the thermostat through its neck and start the engine. The liquid will gradually drain away, so add it as you go. To make the air come out even faster, you can squeeze the upper pipe with your hands.”

Don't rush, everything will be fine

“Many people ask how much antifreeze should be added. So, pour the “coolant” up to the mark and at the same time squeeze the pipes, then close the lid. Start the engine and warm it up until the radiator fan starts running. Next, increase the speed to 3000 and hold it for a minute. Turn off the engine and wait until it cools down completely. Then start the car again and, with the engine running, add antifreeze to the mark.”

No topping up, change everything

“I think that instead of constantly topping up, it is better to completely drain the liquid and pour fresh antifreeze into a clean, washed system. Never choose by the color of the liquid! Focus on the classes of antifreeze available on the market: G11 (there are blue and green) and G12 (in my opinion, only red). True, there are also red G11 fluids from Castrol. There are other nuances when choosing antifreeze. For example, it is impossible to use a more modern G12 instead of a previously filled G11, since the system is most likely not designed for the aggressive new composition.”

Do not interfere and be careful

“The best option is to record the name and class of the antifreeze poured in and only fill it in the future. If this is not possible, you will have to constantly completely change the fluid in the cooling system.”

Why change the coolant?

Without a coolant, correct operation of a car engine and operation of the vehicle . Below we will explain how to change antifreeze (antifreeze), but first you need to dwell on why you need to do this in the first place.

Coolant replacement

Today there is a huge range of products available for sale that are intended for pouring into the cooling system. The driver can only choose the best option and regularly replace the coolant. This will insure you and your car against serious problems. Including:

1. Corrosion processes. In addition to corrosion damaging the metal parts of the system, it becomes an obstacle to proper heat exchange directly in the system and in the power unit. At the same time, corrosive layers in the radiator channels reduce the rate of coolant circulation and reduce correct heat transfer.
2. Overheating of the power unit. If heat exchange in the engine is disrupted, the likelihood of overheating increases. This leads to increased fuel costs and decreased engine power.
3. Precipitation. Typically, this “suffers” from antifreezes that have silicate components in their composition. Failure to replace these products on time results in the formation of insoluble sediment on the surfaces inside the system, which causes overheating of the engine.
4. Appearance of cracks. If the coolant is excessively diluted due to sudden temperature changes, cracks appear on the surfaces of the expansion tank and pipes.
5. Erosion processes of cavitation type. Cavitation is a process occurring inside a system in which gas bubbles form and burst due to a decrease in pressure. The internal surfaces of the system are damaged at the molecular level when gas bubbles collapse. High-quality coolant forms a protective film that prevents erosion.

How to replace coolant using the example of a VAZ-2110

First, let's look at how the replacement is done on a VAZ-2110 car. This car uses a design that includes an expansion tank. Additionally, this model is interesting because it has a drain plug on the cylinder block, which is not found on all cars.

Video: Replacing the coolant. VAZ 2114

Tools you will need:

• a set of wrenches (open-end, spanner);
• container for collecting coolant;
• rags.

You should also stock up on the required amount of antifreeze. This information can be found in those. documentation for the vehicle, in the “refill tanks” section. You can also buy undiluted antifreeze, but its concentrate. But here you will additionally need a distillate and knowledge of the proportions to properly mix the solution.

So, having everything, you can start replacing, which is done like this:

1. We place the VAZ-2110 on a flat surface, immobilize it and remove the terminal from the battery to prevent accidental shorting of the wiring contacts.
2. First, the liquid is drained from the cylinder block, the drain plug of which is located on the right side (if you are in front of the car) under the ignition module.
3. We remove the ignition module from the car, for which we disconnect from it the high voltage wires going to the spark plugs and the block with regular wires. We unscrew the three bolts securing the module and remove it, then remove the cover from the expansion tank.
4. Below this module there will be a plug, which is a regular 13mm bolt. Before unscrewing it, place a collection container under the car (a good option is a 5 liter plastic canister with a cut out side). We unscrew the plug and wait for the coolant to drain from the block. As soon as it stops leaking, replace the plug and tighten it. We wipe the engine with a rag to remove any antifreeze stains. We put the module in place and connect it.
5. We look for a bolt with a wing head on the radiator at the bottom - this is the radiator plug. It is installed at the bottom left. Place a container under it and unscrew it. If you can’t do it with your hands, you can use a regular open-end wrench size 17. Drain the coolant from the radiator completely and replace the plug.
6. Let's start filling in new antifreeze. To do this, gradually, in several passes, pour antifreeze into the tank. He will go away slowly. It is important to ensure that the antifreeze level in the tank is at “Max” after the system is filled.
7. We start the engine and monitor the level. It is necessary to ensure that the motor reaches the optimal temperature regime, after which the thermostat will open and release liquid in a large circle. At the same time, the coolant in the tank will begin to quickly leave. After this, we bring the level to “Max” and put the tank cap in place. The coolant has been replaced.

When to change coolant

Some drivers prefer to change the coolant seasonally, while others prefer to change the coolant based on the number of kilometers the car has traveled.

If you change it according to mileage, it is recommended to change it every 40-50 thousand km. During diagnostics and maintenance of the machine, the coolant (antifreeze, antifreeze) must be checked for contamination and level in the system.

Do you know what a coolant temperature sensor is? No, that's not right. This is a sensor that displays the temperature value on the instrument panel.

Recommendations from antifreeze manufacturers

The period for replacing the coolant depends on the type of antifreeze.

Conventional compositions (including TOSOL), created using traditional silicate technology, correspond to category G11 according to the generally accepted classification of the Volkswagen automobile concern. Such fluids are replaced after 2 years of operation, but during intensive driving, the antifreeze may expire earlier - after 60,000 km (depending on which comes sooner).

Antifreezes manufactured using more modern technologies belong to higher classes G12, G12+, G12++, G13. They last much longer, so manufacturers of such compounds recommend changing them less frequently.

For example, G12 cooling solutions retain their protective properties for 5 years of operation (up to 150,000 km), and manufacturers allow G13 class fluids to be changed after 200,000 km.

Recommendations from car manufacturers

Any automaker develops instructions for operating and servicing their vehicles. Among other routine maintenance, such documents must indicate what type of fluid is used in the cooling system and how often it needs to be changed.

Please note that these terms are indicated for average operating conditions in a temperate climate zone on good roads with a calm driving style. More severe modes make their own adjustments to the service intervals - in these cases the antifreeze will have to be changed earlier than the car manufacturer indicates.

Choosing quality antifreeze for a car

A lot depends on the characteristics of the coolant: the safety of the car, the durability of the pump and radiator, and the efficiency of the interior heater. Therefore, preference should be given to high-quality materials manufactured in strict accordance with GOST and ISO standards.

Antifreeze ROLF G11 Green

ROLF products meet all requirements and consumer demands. The range includes antifreeze of different brands: G11, G12 and others. A wide variety of coolants makes it easy to select the appropriate composition for a specific car model, taking into account the characteristics of the radiator, engine and other components.

Replacement frequency

The question of how often to change antifreeze in a car cannot be answered unequivocally. It all depends on the type of fluid, vehicle operating conditions and other factors.

For example, in older model cars with high mileage, antifreeze will need to be changed more often than in new ones. The thing is that worn-out engines have multiple pockets of corrosion. Trying to neutralize them, antifreeze absorbs harmful substances and loses its own beneficial properties.

In new cars, antifreeze is changed, on average, once every three years or every 60 thousand kilometers (with more intensive use).

In old cars or in cars with high mileage - once every 40-50 thousand kilometers traveled (usually guided by the appearance and consistency of the antifreeze).

It is better to make a decision about replacing the coolant based on the recommendations of its manufacturer or the car manufacturer.

Manufacturers' recommendations

When setting deadlines for replacing antifreeze, their manufacturers are guided, first of all, by the type of refrigerant.

The most common is the classification developed by the Volkswagen concern.
It divides coolants into 3 categories:

• G11: traditional antifreeze with inorganic additives; form a physically tangible layer on the surfaces of engine parts that prevents corrosion; if such antifreeze is not replaced on time, it precipitates, and particles clog the system components; The recommended replacement interval for fluids of this class is 2 years;
• G12: coolants produced using organic (carboxylic) acid technology; have excellent heat transfer properties and do not create integral protective layers, like traditional ones; corrosion inhibitors act precisely on specific areas, preventing their further spread; over time, the properties of carbon deteriorate, so it is recommended to change antifreezes of this type, as well as improved hybrid (G12+) and carboxylate (G12++) fluids every 5 years;
• G13: the latest generation of lobride coolants based on propylene glycol (others use ethylene glycol); their properties are similar to carboxylate ones, but due to a more reliable and environmentally friendly base they have the longest service life - up to 10 years; Some manufacturers do not recommend changing antifreezes of this class at all.

It is worth noting that it is wrong to focus only on the replacement interval in years. Over several years, the mileage of each car is different, so manufacturers use average data. The manuals also indicate antifreeze replacement intervals in kilometers. For traditional refrigerants it is 60-120 thousand km, for carboxylate refrigerants – 250 thousand, and for lobride refrigerants – over 250 thousand.

Each automaker has its own recommendations for replacing antifreeze. Thus, the Volkswagen and General Motors concerns provide a lifetime warranty on coolants poured into their cars on the assembly line.

Ford is more “modest” and guarantees 240 thousand km, AvtoVAZ – 75 thousand km. Mercedes, BMW and Mitsubishi promise 4-5 years of operation.

How to determine that antifreeze has exhausted its resource?

A change in the appearance of antifreeze indicates its unsuitability for further use - even if the period for replacing the fluid according to the manufacturer’s recommendations has not yet come.

Replace antifreeze immediately if you notice:

• Severe cloudiness or discoloration of the fluid
• Sediment in the form of flakes
• Mechanical particles in the refrigerant
• Enhanced foaming even with the slightest vibrations
• Thickening, “gelling” of liquid
• Significant reduction in antifreeze volumes

Replacement frequency

Before we talk in detail about how to change the coolant in a car, let’s focus on the regularity of this procedure. There are general recommendations regarding the frequency of replacing the refrigerant - approximately once every 24 months or every 45,000 km. The period for replacing the coolant is determined based on factors such as the technical condition of the car and its actual mileage, the brand and composition of the coolant itself, as well as the product used previously.

Fluids with silicate additives must be replaced every 24-36 months. Combined formulations lose their working properties after 36-60 months, and products with a carboxylate base can “work out” for more than 5 years.

How to replace antifreeze
Today, there are carboxylate compounds that are designed for a mileage of 100,000 km or more, but their range is not yet so diverse.

But often, the coolant loses its performance qualities somewhat earlier than the deadline . That's why you need to check its condition sometimes. Here are several options that allow you to accurately determine that it is time to replace the coolant:

• using a special test strip - this is the most reliable and affordable way (you can buy it together with the coolant): “litmus”, immersed in the solution, changes color, which makes it clear how long the fluid will last before being replaced (a color scale is usually attached to the test);
• coolant density, which changes in the spent mixture;
• color of the working composition - coolant that has lost its properties, does not have a bright color, becoming more faded/cloudy (at the same time, a red/reddish tint indicates the presence of rust in the coolant and the use of such a composition is extremely undesirable);
• the presence of clots, foam, flakes and scale, as well as sedimentation or the formation of a mushy mass inside the expansion tank is a clear sign that the coolant needs to be changed.

The suitability of the coolant can be easily determined visually or using special means. Timely replacement of the fluid helps maintain the good condition of the power unit cooling system and avoid expensive car repairs.

How to change antifreeze

Possibility of mixing different types of liquid

The answer to this question is very simple and short; you cannot mix any antifreeze or different types.

This can result in some hard or jelly-like deposits that can clog the cooling system passages.

In addition, as a result of mixing, foaming of the cooling solution may occur, which can lead to overheating of power units and very serious consequences and expensive repairs.

Consequences of untimely replacement

Irregular maintenance of a car's cooling system can lead to many problems.

• Due to a large amount of deposits, the working channels of the circuit may become clogged, as a result, coolant circulation will stop and the engine will overheat.
• Insufficiently efficient heat removal from the engine can cause thermal deformation of the cylinder head. The expensive cylinder head will have to be replaced.
• Spoiled antifreeze negatively affects the condition of the pump, radiator, pipes and other elements of the cooling system. One of the possible results of a late coolant replacement is the cost of purchasing the listed parts.

Types of antifreeze and rules for mixing them

The key components of antifreeze are identical: 80% - ethylene glycol and purified water without impurities. The remaining 20% ​​is an additive package that makes the “face” of the coolant. The color, anti-corrosion qualities, service life and price of the refrigerant depend on the additives.

There are no uniform standards for antifreeze, but the composition classification created by VW is used: G11, G12 and G12 plus, G13.

Not every type of coolant is popular in the domestic market:

• green (G11);
• red (G12);
• blue (antifreeze).

There are also purple and yellow refrigerants, but they have not gained popularity in Russia.

Antifreeze is blue antifreeze.

Ingredients: ethylene glycol and purified water. There is also red antifreeze, its main difference is the boiling point.

This type of refrigerant contains a generally accepted package of additives: silicates, phosphates, borates, nitrites, etc. Real chemistry, in other words. Today it is considered obsolete.

Flaws:

• The maximum replacement period is two years, and with large kilometers the antifreeze needs to be changed frequently, every 6–12 months.
• The main substance in its composition (ethylene glycol) is toxic and can be fatal.
• Each of the additives does its job.
• Forms toxic compounds.
• Low boiling point (+110...+115 °C) – it may well boil in some foreign cars.
• A highly aggressive composition, foreign cars may not even start.

Advantages:

• Low price with average efficiency.
• At -36 °C it freezes and becomes jelly-like.

G11 – green antifreeze.

It has a more advanced composition, and can also be yellow and blue. Basic manufacturers adhere to a single color scheme for the refrigerant - this is a kind of standard. Contains not only chemical, but also organic additives. Compared to antifreeze, it is slightly aggressive (it contains phosphates, silicates, borates and a small amount of carboxylic acid). This liquid envelops the walls of the cooling system of the machine, fights the center of corrosion and localizes it.

Advantages:

• fights corrosion processes;
• envelops the walls of the cooling path with a protective film.

Flaws:

• reduces heat dissipation;
• the film is short-lived and, when shed, forms a deposit in the cooling system;
• The antifreeze in the car needs to be changed every 2-3 years;
• It is prohibited to combine with other types of refrigerant.

Additionally, G11 plus antifreeze is produced. Its difference is in the amount of carboxylic acid (the greater it is, the closer to G12).

The green refrigerant of this series is most similar to domestic antifreeze and can conditionally be classified as group G11, although there is no such designation in Russia.

G12 – red antifreeze.

In the production of this type of coolant, a lot of carboxylic acid is used, so it is practically organic.

Additives cover the walls with a non-shedding film of just one micron, due to which they effectively fight corrosion.

Advantages:

• good heat dissipation;
• the film does not crumble;
• Antifreeze does not need to be changed so often - it lasts up to 5 years;
• fights corrosion;
• contains no silicates.

Flaws:

• localizes only corrosion pockets, but does not protect the cooling system;
• does not protect aluminum radiators;
• Do not combine with other antifreezes containing ethylene glycol.

G12 plus is a hybrid. It contains no chemicals (silicates, nitrates, etc.), so it combines well with other types of coolants.

G13 – purple antifreeze.

This type of refrigerant was created in 2012. Manufacturers dyed it purple and replaced the toxic ethylene glycol with propylene glycol. The result is a safe, gentle mixture. The additives remained the same - carboxylic acids and silicates.

Advantages : absolutely harmless.

Disadvantages : more expensive than analogues due to the replacement of ethylene glycol with propylene glycol.

Why does antifreeze change color?

The manufacturer has the right to paint the product in any color. There is a generally accepted, but not mandatory, coloring scale:

• G 11 is painted blue, green;
• G 12 red, including all accompanying shades (orange...lilac);
• G 13 purple or pink.

Let's look at why antifreeze changes color. During operation, additives are produced and a change in coolant color becomes an indicator. For some brands, the indicator is discoloration rather than a change in shade.

How often should antifreeze be changed completely?

A car is a complex technical device, so manufacturers always provide it with an instruction manual, which describes in detail all routine maintenance procedures.

As for the coolant, it is recommended to change it at certain intervals depending on the mileage of the car. For each specific brand of engine, different mileage may be recommended, but on average it is 30,000 km or approximately 2-3 years of car service.

If your car's mileage has exceeded the recommended distance, but you think it is premature to change the antifreeze, it is better to check the coolant level by looking into the reservoir.

Manufacturers usually make coolant reservoirs translucent, with minimum and maximum level markings, so you can easily determine the amount of antifreeze by eye. It is also advisable to dip your finger into the reservoir to determine the consistency of the coolant.

It is necessary to completely drain the antifreeze if:

• Its service life has expired
  . The recommended replacement interval is after every 30,000 km.
• The color has changed
  . This situation signals a deterioration in the performance of antifreeze due to the presence of impurities. Brown, black, pale and especially red coloration is grounds for replacement.
• The consistency has changed
  . The coolant should be thick and slippery to the touch. If it looks like ordinary water, it means that you urgently need to drain the antifreeze completely.

If you doubt the suitability of antifreeze and cannot determine its quality by appearance, you can measure the density of the liquid using a special device - a hydrometer. The normal value is considered to be a density of 1.075 g/cm³.

A hydrometer will also be useful to you when buying a new coolant - it can be used to easily check how high-quality the antifreeze is.

Antifreeze: change or top up?

The additives stop working, the water evaporates, and periodic renewal is needed. If you add only distillate, there will not be enough substances to protect the system.

If the level is low, check the system for leaks. If none is found, it is worth topping up.

Compatibility of compositions of the same color is optional (see above). To choose the right coolant, you need to follow the car manufacturer's recommendations. Different liquids should not be mixed. The reason is that additives can neutralize each other and react. Such a substance will not protect/cool.

Preparing antifreeze before filling

To obtain the required temperature parameters and save money, before using antifreeze, it must be diluted with water. It should be taken into account that the resulting crystallization temperature is related to the type of boiler: if a gas and electric boiler is used in the system, the permissible crystallization threshold is not higher than -20º C; when operating boiler equipment using liquid and solid fuels, the threshold is reduced to -25º C.

Due to the nonlinear dependence of the crystallization point on concentration, when diluting the coolant, they are guided by tabular data (Fig. 9). It is clear from them that if, for example, we have a 68% composition with crystallization at -65º C, then to achieve a coolant temperature of -20º C, corresponding to a 36% glycol content, we will have to dilute the purchased composition with water a little less than half.

If you purchased an anti-freeze solution with a temperature limit of -30º C and a glycol concentration of 45%, then to crystallize the coolant at -20º C with a 35% amount of glycol, you will have to add 22% of the total volume of water to the liquid.

Rice. 10 Characteristics of Antifreeze

What can replace antifreeze?

During operation of the internal combustion engine, sometimes the seal of the cooling system breaks down and the engine begins to heat up.

If you do not have the opportunity to quickly resolve the malfunction, then you need to add coolant solution before visiting a service station. In this case, you can add plain water, preferably distilled.

But you need to remember that such topping up increases the freezing point of antifreeze. That is, if the system depressurizes in the winter, then you need to eliminate the leak as quickly as possible and change the cooling solution.

Several signs that antifreeze needs to be replaced

The most important sign that indicates that antifreeze needs to be replaced is a change in its color.

If the antifreeze has become cloudy gray or dirty, you need to drain it, flush the system and add new fluid.

If, upon visual inspection, it is determined that the antifreeze has become thicker and darkened, this also indicates that it has partially lost its beneficial qualities and must also be replaced.

During the operation of the vehicle, unforeseen situations may arise in which the tightness of the cooling circuits is compromised - breakage of pipes or cracking of hoses, pipes, plugs. This leads to a decrease in the fluid level in the system. In this case, you also need to eliminate the malfunction and add antifreeze.

Some types of repair work also require complete or partial drainage of the fluid. Upon completion of this work, its level must be replenished.

How much coolant do I need to replace?

The exact volume of coolant solution is indicated in the operating instructions for each car model. However, there are some general points.

For example, in engines with a volume of up to 2 liters, up to 10 liters of coolant solution and at least 5 liters are usually used. That is, if you consider that antifreeze is sold in 5-liter canisters, then to replace the cooling solution you will need to buy at least 2 canisters.

However, if you have a small car with a volume of 1 liter or less, then one canister will probably be enough for you.

What volume should I pour?

Before purchasing antifreeze, drivers are wondering about the amount of liquid that is used in the cooling system. This figure is indicated in the instruction manual. Typically, for passenger cars with an engine capacity of up to two liters, 7-8 liters of antifreeze must be used. For example, the domestic “ten” requires 7 liters of liquid. For SUVs like UAZ Patriot - 12. The least needed for Oka is 4.8 liters. Engines produced by ZMZ, which are installed on the Volga and Gazelle, require about 10 liters of coolant. But in any case, it is necessary to fill antifreeze to the mark that is between the maximum and minimum.

Remember that as the temperature increases, the liquid expands and needs additional volume, which is compensated by the expansion tank. If you overfill antifreeze, it may simply explode or flow out of the pipes under enormous pressure.

How to flush the cooling system before replacing antifreeze

Why is it necessary to clean the system when replacing the coolant:

1. Removing turbidity and contaminants that impede the free movement of liquid matter. As a result, heat will be transferred faster.
2. Ridding the system of the previous coolant before replacing it with fresh one. This must be done to prevent a chemical reaction of the components in the two types of antifreeze. As a result, the anti-corrosion properties of the new fluid will be weakened.

Twenty or thirty years ago, flushing the cooling system was done using traditional methods. For example, the radiator was filled with a solution of citric acid or vinegar. Today there are special means, the use of which will bring greater effect; the engine cooling device will be completely cleaned.

Means for flushing the system before replacing the coolant are divided into 4 types:

• Two-component liquid.
• Alkaline solution.
• Neutral composition.
• Coolant replacement product consisting of acids.

In the sediment that accumulates in the cooling system, two types of substances can be distinguished: those formed during the breakdown of antifreeze (destroyed by alkali); rust and scale (dissolved by acids).

It is impossible to develop a washing liquid that would consist of both alkalis and acids at the same time. The mutual neutralizing effect of alkali and acid is known. Therefore, the cleaning solutions that are on sale today contain one thing in their composition: either alkali or acid. That is, these products can only remove one type of sediment.

There are cleaning fluids consisting of two components. The action occurs in sequence: in the process of replacing the coolant, the system is first cleaned of one type of contaminant, then of the second. Such cleaning solutions are more effective, but will require more time. And the price of such funds is rather high.

Replacement nuances

It is strictly forbidden to drain antifreeze from a hot engine. When carrying out the procedure “hot”, you risk getting serious burns as a result of the release of hot liquid or steam from the system. In addition, care should be taken to protect your hands, respiratory organs and eyes. Antifreeze is an extremely toxic substance, the components of which cause chemical burns if they come into contact with unprotected areas of the skin. In turn, antifreeze fumes cause irritation of the respiratory tract, drowsiness and, in certain cases, loss of consciousness. Upon completion of the work, it is necessary to drain the used coolant into a sealed container and send it for recycling.

If the drained antifreeze has a brown or orange tint, and there are traces of corrosion or scale on the walls of the pipes, the cooling system must be cleaned. This can be done using a specialized cleaner, distilled water or a weakly acidic solution of citric acid. This solution can be prepared by mixing citric acid and distilled water in a ratio of 15 grams per liter.

The cleaning procedure itself follows the following algorithm:

1. We pour the liquid of our choice into the cooling system and start the engine for 5-7 minutes.
2. Drain the cleaner, add distilled water and repeat the procedure.
3. Drain the water and add antifreeze.

Mixing coolant is allowed provided that both fluids belong to the same class. In emergency situations, you can mix products from different classes. After this, it is urgent to replace the mixture followed by flushing the entire system. This is due to the fact that the substances that make up the coolant can react unexpectedly with each other, which will cause serious damage to the cooling system.

Radiator flushing

To clean technological channels from oxidative sediment and rust, special chemical additives or folk cleaning products are used. You can remove salt deposits using citric acid, soda and even cola.

To prepare the compositions, carefully read the instructions. Additives are mixed in certain proportions, and the period and method of washing differs in the time of exposure of the reagent in the system.

Washing steps and sequence:

• prepare a solution,
• fill the system and close the drain holes,
• start and warm up the engine according to the mode specified in the additive instructions.

After working for some time (up to 30 minutes or driving 10 - 15 km), wait until the engine cools down.

We also recommend that you additionally read the article on how to properly flush the engine cooling system.

For more detailed information on how to remove air from the engine cooling system, read the article by our specialist.

You can read about the features of checking and repairing the cooling system of the VAZ 2107 in the material of our author.

Useful tips

As practice shows, experienced car enthusiasts know how much coolant is in a particular engine and how to change antifreeze in a car. It would seem that everything is simple, we drained the old coolant, prepared and filled in a new one to the level, and also, if necessary, got rid of air pockets. However, this is not all.

Unfortunately, not everyone takes into account that the service life of the new coolant also directly depends on the quality of the replacement itself. In other words, you need to consider how to change antifreeze correctly. In this case, the features of the replacement will depend on certain features.

First of all, if the system is initially clean, and exactly the same antifreeze is poured as it was before, then you can limit yourself to the usual replacement of antifreeze according to the “drain and fill” scheme.

In this case, it is important to drain the antifreeze from both the radiator and the engine (if possible). If rust and contamination are noticeable in the antifreeze or a transition is made from one type of coolant to another (for example, from TOSOL to G12+ antifreeze), then the engine cooling system must be flushed before replacement.

It is better to flush with ready-made compounds from well-known brands, although for many internal combustion engines simple methods of flushing the cooling system with citric acid, etc. are also suitable. Flushing should be carried out from one to 2-3 times (depending on the overall degree of contamination of the system).

It is quite obvious that this approach will allow you to get rid of the remnants of old fluid in the system and avoid mixing used and new coolant. Flushing also allows you to remove rust, scale and deposits from parts of the cooling system. Let us also add that for different cooling systems, car manufacturers recommend using only the recommended type of antifreeze. So, this recommendation is also quite important.

In short, a situation may arise when, after filling in the wrong type of coolant, individual elements of the cooling system begin to deteriorate, corrosion becomes more active, etc. It is not difficult to guess that in this case, both the service life of the antifreeze and the parts and elements of the engine cooling system itself will be noticeably reduced.

Replacing coolant: step-by-step instructions

Let's summarize the above. How to properly replace antifreeze? Main points.

1. When you decide to change your car's engine coolant, first read the owner's manual. It usually recommends when to change the antifreeze.

   By referring to the instructions and finding the necessary information, find out the desired date for replacing the coolant. Perhaps there will be some recommendations in this regard in the manual.

2. Buy a solution that is suitable for your vehicle. In supermarkets and car stores there is a large selection of coolants; you can find a composition that matches the characteristics of any car. You will also need a tray to collect used coolant and a container in which a new solution (antifreeze with water) will be prepared.
3. Next, it is necessary to carry out a number of preparatory work. If you are going to change the coolant yourself, park the car next to the hose. It is advisable that this be a flat place, not on a slope. The machine should be completely cool, let it sit for a while. Then start the car, let the engine run for a while so that the temperature in it can be measured. Its value should correspond to the parameters of a cold motor. Then you need to turn on the stove and remove the key from the ignition.
4. Draining the previous antifreeze. Remove the radiator cap (it is located in front of the engine). Usually there is an inscription on it that it is forbidden to open the cover when the engine is hot. There is a coolant drain plug at the bottom of the radiator for replacing it. Place a tray under the plug and carefully remove it. This can be done with a screwdriver, another tool, or just with your hands. Wait until the liquid has completely drained out. If there is no hose, a pump may be needed for this. Flushing the system may not be necessary if you change antifreeze frequently. But in the case when this operation was performed a long time ago, the radiator needs to be cleaned.
5. Then fill the system to the brim with coolant dissolved in water (in equal proportions). Close the radiator cap. If there is still a reservoir, fill it halfway. After this, turn on the engine with the heater. Let them run for a while, the air should come out of the system. Look at the temperature sensor to see if the car is overheating. Air bubbles that appear in the radiator indicate that it is time to turn off the engine. Fill the radiator with antifreeze and close the radiator cap. For several days, periodically look at the sensor showing the temperature.
6. The solution drained as a result of replacing the coolant must be disposed of. It is recommended to place it in a securely closed container out of the reach of children. Write “used antifreeze” on the container. Then you should take the liquid to any gas station, where it will be disposed of according to all rules.

Coolant replacement stages

Knowing how to replace the coolant in a car, every car owner will be able to cope with all the steps independently. We emphasize that the sequence for replacing the coolant is similar for all cars :

1. The spent working composition must be completely drained.
2. Thoroughly flush the power unit cooling system.
3. Pour in new working mixture.

Draining the used refrigerant

To completely drain (without any remaining) coolant, it is advisable to lift the rear of the car . To do this, you can use a jack, but other improvised means may also work.

Having lifted the rear of the car, you can proceed directly to draining the coolant. Almost all power units have a special tap or drain hole at the bottom with a securely fixed plug. It is through this element that the coolant is drained from the cylinder block. In addition, it is necessary to remove coolant from other parts of the system - the radiator and expansion tank. This is done as follows:

1. Loosen the expansion tank cap - this allows the working mixture to flow out faster.
2. Roll up the plug for draining the working fluid from the engine cooling jacket into a container prepared in advance, placing it under the drain hole.
3. Unscrew the drain valve (remove the plug at the bottom of the radiator) - this allows you to remove the coolant from it.
4. The coolant pressure can be adjusted by unscrewing/tightening the expansion tank cap. After finishing draining the working mixture, return all drain elements to their place.

Important! Before you start draining the coolant, you need to “de-energize” the car by disconnecting the battery!

Cooling system
Let us remind you that there is a special drain valve on the radiator, but you can get to it only after dismantling the bumper. And if we talk about AWT or AZM power units, then to drain the working fluid, you need to dismantle the thermostat by unscrewing the elements securing it. Having finished draining the coolant, the thermostat must be returned to its place, and the fasteners must be tightened taking into account the prescribed tightening torque.

Flushing the radiator

After draining the used coolant, it is necessary to rinse the radiator thoroughly . This is done to clean the channels of the cooling system, remove rust and other “garbage” that impede the stable and efficient functioning of the system.

1. Disconnect the radiator hoses, then place the special hose in the fitting at the top.
2. Run regular water into the supplied hose. The liquid pressure must be good so that the liquid through the pipe from below removes the contaminants accumulated in the system. You need to add as much water until it comes out clean, free of various impurities and debris. For more effective and quick cleaning, you can use special cleaning products for the cooling system.

In case of heavy contamination, the radiator is flushed using countercurrent . To do this, you need to dismantle it and install a hose through which clean water will be supplied into the pipe from below. The water moves in the opposite direction and will pour out of the pipe from above.

Expansion tank

My power unit

Flushing the car’s engine when completely replacing the coolant is an equally important step . The sequence of actions at this stage is as follows:

1. Remove the thermostat without touching its cover.
2. Disconnect the hoses coming from the radiator, and just like in the previous step, place the hose in the pipe from above.
3. Run water into it - it should flow into the power unit. Washing continues until the liquid pouring out from below is completely clean.
4. Place the thermostat back and reconnect the hoses.

Products intended for flushing the system

Until recently, motorists used a variety of folk methods to flush the elements of the cooling system. For example, vinegar (70% solution) or a strong solution of citric acid was poured into the radiator. But today there is a sufficient selection of special products on sale that most effectively clean the most important components of the system.

are ideal for flushing the system . Before use, the rinsing concentrate must be diluted with water in the proportion specified in the instructions for it. Flushing the system using such products is called “soft flushing”.

The key advantage of such a wash is the function assigned to it, namely, pre-priming . This means that a certain amount of additives contained in the product settles on metal surfaces. And when fresh working fluid is added, it will work much more efficiently, since the environment has already been properly prepared for it. In addition, oxidation processes will slow down.

Refilling with new antifreeze

Coolants on the market

There are several main types of coolant: standard, hybrid and carboxylate (G11, G12+). The main component used for production is ethylene glycol. To classify additives, marked symbols are used to indicate functional features. The most popular are anti-foam and anti-corrosion additives.

1. Traditional antifreezes (Tosol) are made on the basis of silicates. The principle of operation is to cover the internal elements of the cooling system with a protective film, which thickens as the mileage passes. When the engine overheats (more than 105 °C), the film is destroyed and precipitates in flakes.
2. Hybrid versions are made from carboxylic acid. Service life without replacement is up to 2 years. Their peculiarity is the formation of a protective film only in areas with elements of corrosion.

What level of antifreeze should be in the expansion tank?

When the lubricant level in the engine is insufficient, an indicator should appear on the dashboard to warn the driver of this problem. However, the cooling system most often is not equipped with special sensors. Therefore, determining that the antifreeze level should be higher can be difficult. The car owner continues to operate the vehicle, not realizing that there is not enough antifreeze. After all, coolant can leak out little by little over a long period of time.

There are often cases when the antifreeze level is insufficient because there is a leak through a leaky joint, damaged pipes or radiator. In addition, the cause of this problem may be a defective cylinder head gasket. As a result, the antifreeze mixes with the oil in the engine. All this leads to the fact that the engine parts will be poorly lubricated. It is clear that operating a car in such a situation will end in its breakdown.

For this reason, it is important to know what the antifreeze level should be and check it periodically.

How to find out the level of antifreeze that should be? To do this, you need to inspect the expansion tank into which antifreeze is poured. The tank will have the following inscriptions: “Min” and “Max”. The optimal level of antifreeze should be such that it reaches the middle of the distance between the minimum and maximum values.

However, it also happens that the inscriptions are missing. What should the antifreeze level be in this case? Carry out a visual inspection; the antifreeze in the tank should be 50% of its volume. When it is not possible to determine the antifreeze level in this way, you should measure the depth of the tank. To do this you need to use a clean stick. Then, if necessary, you should add antifreeze, focusing on the fact that its level should be up to half the tank.

Important: you can only use antifreeze recommended by the car manufacturer. When you add coolant, it must match the markings and shade of what is already in the tank. The antifreeze level should not be less than that on the expansion tank

Also, you should not overfill antifreeze above normal. In both the first and second cases, the machine will not work properly.

The antifreeze level should not be less than that on the expansion tank. Also, you should not overfill antifreeze above normal. In both the first and second cases, the machine will not work properly.

• The antifreeze level is below normal. As a result, the small circle will not be filled. All this will lead to the motor overheating and operating at elevated temperatures. In the best case, the car will begin to consume more fuel, and the channels and tubes will crack. In the worst case, the life of the motor will be sharply reduced, it will fail ahead of time, it will simply jam. The same thing should happen if you operate the car without antifreeze at all.
• The antifreeze level is higher than normal. Of course, some car owners believe that if they add a little more antifreeze than normal, this will save them from adding coolant in the future. However, do not forget that after heating, antifreeze expands. As a result, if its volume is greater than permissible, the pressure in the system will increase. This will lead to the tank cap being ripped off and the system depressurizing. A leak will appear, and then the antifreeze will simply pour out of the tank. If the antifreeze level is too low, the engine will fail.

Every driver should check the antifreeze level regularly; it is recommended to do this every 7 days. This is the only way to keep the engine in good condition and detect a leak or depressurization of the cooling system in time.

Please note: since antifreeze is a liquid, it should evaporate over time. After all, the system cannot be 100% sealed.

Therefore, the antifreeze level will gradually drop. Antifreeze boils at a temperature of 120 °C. If the cooling system is faulty, you may notice clouds of steam coming from the engine compartment. This indicates that the car owner must be prepared for the costs of major engine repairs.

Some useful tips on how to drain antifreeze completely

The operating manual for each specific car describes in detail how best to completely drain the antifreeze from the engine. Sometimes a lift or trestle is needed, but you can get by with a jack to lift the car from one side.

General recommendations:

• The used liquid must be drained into a previously prepared container, avoiding contact with the ground and other surfaces, since the coolant contains substances harmful to human health and the environment.
• The antifreeze collected after replacement must be disposed of in accordance with the established procedure. Sometimes it is added to the liquid in the heating system of private buildings, but in this case the expansion tank must be installed in a room with good ventilation.
• If you need to drain antifreeze, follow all safety precautions and wear protective clothing. If coolant does get on exposed areas of the body, wash them with plenty of water and detergent.
• Used antifreeze should not get on the body and engine elements, as it can lead to corrosion.

Examples of what else antifreeze can be useful for

• they can be useful for preventing breakdowns in the motor due to its heating or strong cooling during operation, as well as for preventing damage to the sealing elements in the motor and pipes;
• modern antifreezes can be used to dissolve or remove internal working scale from the surface of pipes, as well as to remove sediments resulting from engine operation;