How to remove an air lock: instructions on how to properly remove air from the cooling system, heater and radiator yourself

The sealed volume of any vessel has a volume limitation. The automotive cooling system should contain only coolant (antifreeze, antifreeze, some use water). Therefore, the presence of air in the cooling system is unacceptable, because it completely stops or disrupts circulation in the system, and you should know how to expel an air lock from the cooling system.

Protection against air lock formation in the cooling system.

General recommendations for prevention

The first thing you need to pay attention to is the level of antifreeze in the cooling system.
Always monitor it and, if necessary, add it. Moreover, if you have to add coolant very often, then this is the first call indicating that something is wrong with the system, and additional diagnostics are necessary to identify the cause of the malfunction. Also check for stains from antifreeze leaks. It is better to do this in the inspection hole.

Remember to periodically clean the cooling system. You can read how and by what means to do this in the relevant articles on our website.

Try to use the antifreeze recommended by your car manufacturer. Make purchases in trusted, licensed stores, minimizing the likelihood of purchasing a counterfeit. The fact is that low-quality coolant can gradually evaporate during repeated heating, and instead of it, an air plug forms in the system. Therefore, do not neglect the manufacturer's requirements.

Instead of a conclusion

Finally, I would like to note that if the described signs of airing in the system appear, it is necessary to carry out diagnostics and check it as quickly as possible. After all, an air lock significantly reduces the efficiency of the cooling system. Because of this, the engine operates under conditions of increased wear, which can lead to premature failure. Therefore, if you detect airing, try to get rid of the plug as quickly as possible. Fortunately, even a novice car enthusiast can do this, since the procedure is simple and does not require the use of additional tools or devices.

Symptoms of airiness

How can you tell if there is an air lock in the cooling system? When this phenomenon occurs, several typical symptoms occur. Among them:

Problems with the thermostat . More specifically, if after starting the engine the cooling fan turns on very quickly, then there is a high probability that the thermostat has failed. Another reason for this may be that air has accumulated in the pump nozzle. If the thermostat valve is closed, the antifreeze circulates in a small circle. Another situation is possible when the coolant temperature needle is at “zero” when the engine has already warmed up enough. Here again, two options are possible - a malfunction of the thermostat, or the presence of an air lock in it.
Antifreeze leak . It can be checked visually by traces of antifreeze on individual elements of the engine or chassis of the car.
The pump starts to make noise . When it partially fails, extraneous noise appears.
Problems with the stove . There are many reasons for this malfunction, but one of them is the formation of an air lock in the cooling system.

If you find at least one of the symptoms described above, then you need to diagnose the cooling system. However, before doing this, it will be useful to understand what caused the possible problems.

Method for removing a traffic jam

Drive onto a flat surface or inspection hole, squeeze the handbrake, turn on neutral; Using a jack, lift the front of the car about 35-45 cm from the surface;

Open the expansion tank cap

Be careful, as careless handling may result in burns;

Start the engine and stove radiator with the temperature set to maximum; Carefully begin adding antifreeze or antifreeze to the expansion tank to the maximum; Increase engine speed to 3000 rpm; Wait until the thermostat opens and begin to squeeze the lower pipe leading to the radiator with your hand. Be careful, carry out the procedure with gloves, following safety rules; Continue doing this until you are sure that the liquid coming out of the expansion tank is clean, without air bubbles; Check the entire lower part of the pipes with your hands, make sure they are hot; Start the stove heater with radiator

Check the supply of hot air flow into the car interior; Lower the car from the jack, secure it with boots for safety; Add the missing amount of refrigerant at a level above average. Never fill at the top level as this may cause expansion and overflow of the lid. Antifreeze particles will corrode the car's paintwork over time; If the airiness is severe, a repeat procedure may be necessary. See this for yourself.

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Second way

Drive the car onto a flat surface or inspection hole, squeeze the handbrake, turn on neutral;
We do not turn off the engine, but warm it up to a temperature of 90°C when the thermostat opens and the liquid begins to circulate in a large circle;
Do not open the expansion tank cap;
We turn off the engine;
Loosen the clamp on the throttle body pipe and remove the pipe. Be very careful and attentive, as temperatures above 90°C can cause burns. Carry out work only with rubber gloves;
Having removed the rubber hose, wait until all the air mixed with antifreeze or antifreeze comes out of it;
We put the pipe back on, clamp the clamp;
We start the engine and test the car. It is advisable to drive both on the highway and around the city at low speed to recheck the system in full.

Remove the air lock from the Priora vehicle

Priora air from the fuel system
Here's how it's done:

the VAZ 2107 tank is checked to make sure there is fuel in it;
the air release fitting on the fuel filter opens;
Fuel is pumped up with a hand pump until fuel flows through the fitting without air bubbles;
without stopping the pumping, close the air release fitting;
Continue pumping until resistance is felt.

Now we need to try to start the engine. If this does not work, it means that air has entered the vehicle and must be expelled from there. On Priora it is done like this:

the union nuts on the injection nozzles are loosened;
the starter spins until the fuel comes out;
Now the nuts are tightened and the engine can be started, as the air will escape along with the fuel.

In this way, the system of the Priora car is de-aired.

The reason for the appearance of an air lock in the cooling system

Cooling systems of modern vehicles are designed for stable high pressure (up to 100 kPa). This design makes it possible to increase the boiling point of the liquid to 120-125 degrees.

However, such a temperature range and effective cooling of the motor are only possible when the system is fully operational. One of the most common problems in the cooling system is the occurrence of air plugs.

The main causes of air locks include:

entry of air through leaky joints of pipes, hoses, tubes due to changes in pressure that occur during the movement of the working fluid of the cooling system, which lead to air being drawn in through loose joints;
injection of air when using a funnel with a wide neck, while in the process of adding liquid, its flow prevents gas from escaping, trapping it in the tank;
increased wear of individual parts of the water pump (fiber, gaskets and seals), through cracks and cracks in which air can be sucked in;

leakage of coolant through pipes, heater and cooling radiators, hoses, which causes a decrease in the level of antifreeze and filling of the free space in the expansion tank with air;
obstruction of the channels in the radiator, which causes cooling problems and the appearance of air bubbles;
malfunction of the valve releasing excess pressure in the cover of the expansion tank, which leads to air being sucked in and the impossibility of releasing it through the same valve;
damage to the cylinder head gasket, leading to coolant entering the oil through the crankcase (a sign is an increase in the oil level and a change in its color) or into the exhaust system (smoke from the muffler becomes white), which causes a decrease in the volume of antifreeze and filling of the free space with air.

How to remove an air lock using the example of a VAZ-2109

To ventilate the cooling system, three methods are used, each of which copes with the task.

The simplest method, which is applicable both for the VAZ-2109 and other cars, is to remove the air lock from the engine. To do this, find a steep slope and drive the car up onto it with the front end up.

Air accumulates at the highest point of the system - in the stove radiator. After installing the car on a slope, the highest point becomes the upper tank of the main radiator, connected by a return pipe to the expansion tank.

After placing the car on the slope, we immobilize it with the handbrake (chocks or other stops will not hurt).

It’s easy to remove air in this way - after installing the car, set the engine speed to medium and hold it. The pump actively pumps liquid and pushes the plug to the top point.

During work, the liquid circulates and its level in the expansion tank may drop, so monitor the amount of antifreeze and add it.

Since the radiator is connected to the expansion tank, when the pump operates intensively, air will first enter the radiator and then be forced out by liquid into the expansion tank.

An indicator that air has left the cooling system will be a stable stream of antifreeze without air bubbles coming out of the return pipe coming from the radiator.

You can remove the cork using another second method.

To do this, find the carburetor heating pipe (throttle valve - on the injection version of the VAZ-2109) and remove it. Then unscrew the cap of the expansion tank and add fluid if necessary.

To expel the plug, create pressure in the system. To do this, blow forcefully into the tank. But it’s easier to find a suitable cap and embed a spool from a tubeless tire into it, then create pressure in the system with a pump or auto-compressor.

The essence of the method is that by creating pressure in the tank, we push the liquid out of the tank. In this case, the liquid, having reached the plug, will begin to shift it to the place where the pressure drops. This is a removed carburetor (throttle) heating pipe. A signal that the plug has come out will be the appearance of a stream of antifreeze from the pipe.

The third method is built on the same principle as the second, but it uses the engine itself to create pressure. We start the engine and let it run for 15-20 minutes (during this time, pressure will build up in the system due to the expansion of antifreeze when heated).

Then we unscrew the carburetor (throttle) warm-up pipe and wait until the pressure causes the plug to come out and antifreeze flows out of the removed tube. But this method is only applicable if the expansion tank cap valves are working properly and do not allow air to pass through.

Using such simple methods, you can de-air the cooling system of the VAZ 2109. The main indicator that the procedure was a success is the restoration of the functionality of the interior heating system. But if the stove does not heat, the procedure will have to be repeated.

Air removal methods

If you observe on the dashboard that the operating temperature of the engine is constantly exceeded (100 degrees or more), follow a number of steps to identify the problem:

examine the joints of the pipes, the water pump and the expansion tank for leaks;
check the fluid level in the tank;
make sure that the cabin heater is functioning properly;
If the temperature sensor is installed outside the cylinder head, check the operation of the electric fan by closing the contacts.

Before bleeding the cooling system, it is necessary to eliminate all leaks, if any are found. A water pump seal that has lost its seal should be replaced (as a rule, together with the pump), hose clamps should be tightened, and so on. There is no point in removing an air lock from a leaking cooling system.

Checking the heater and fan sensor will help you more accurately determine the location of the air bubble. When the engine temperature reaches a critical threshold and the heater does not heat up, it means that the plug is in a small circulation circuit - in the stove itself or in the supply pipes. If the sensor does not turn on forced airflow in time, then it has entered an area where the movement of antifreeze has stopped - the bubble is in a large circuit.

Method one - blowing

This simplest method requires caution from the car enthusiast, since it is performed on a fully warmed-up engine. The order of operations is as follows:

If necessary, add fluid to the minimum level and warm up the power unit to operating temperature. Carefully unscrew the cap of the expansion tank.
Wear gloves and disconnect the thin coolant pipe at the highest point. For an engine with an injector, this is the throttle valve heating unit; on a carburetor engine, it is the intake manifold or the lower part of the carburetor itself.
Wipe the reservoir neck thoroughly. Place a wide bowl under the removed hose and blow into the expansion tank. When clean antifreeze flows from the pipe, put it on the fitting and secure it with a clamp.

If your vehicle has a thermostatic main radiator cap, try removing the air lock through it. Open both plugs and blow into the neck of the expansion tank.

Method two - complete replacement

This option is suitable for all cases when it is not possible to detect and push a bubble out of pipelines. The point is to completely empty the system and fill it back with antifreeze, following all the rules. The disadvantage of the method is the difficulty of implementation in road conditions.

The procedure is performed in the following order:

Drain the antifreeze into a wide basin, placing it alternately under the plug on the cylinder block and the main radiator.
Replace all caps and tighten them.
Loosen the clamp and remove the throttle body or carburetor heater pipe (the highest point of the system).
Insert a funnel into the neck of the expansion tank and slowly pour coolant in a thin stream. Air will be removed through the removed hose.
Monitor the moment when antifreeze runs out of the pipe and immediately put it on the fitting.

Before emptying, be sure to fully open the cabin heater tap.

When the throttle (or carburetor) heating hose is put on and secured with a clamp, add fluid to the container to the required level. Next, check the functionality of the cooling by completely warming up the engine until the thermostat opens and the electric fan turns on.

Method three - road

When faced with overheating of the power unit on the road, try to remove the airlock using this method:

Having secured the car with the handbrake, lift the front part with a jack to a height of 0.3–0.4 m.
Slowly unscrew the expansion tank cap, start the engine and turn on the cabin heater to maximum mode.
Pour antifreeze into the tank in a thin stream until its level reaches the upper limit. Increase the crankshaft speed to 3000 rpm and wait until it warms up completely.
Squeeze the lower hose leading to the radiator with your hand. The air should escape through the expansion tank. Use gloves or thick cloth to avoid getting burned.

The procedure ends when air stops coming out of the tank. Feel the remaining pipes - they should warm up. Make sure the stove produces a hot stream.

To avoid having to fuss with removing air pockets, always fill in antifreeze according to the instructions described in the previous section. This is the best way to force air out of the system. Fix leaks in a timely manner, do not drive with endless additions of coolant.

Malfunction prevention

Instead of eliminating the problem, it is easier to take measures to prevent it. The main rule for protecting the cooling system from outside air is timely diagnosis. The system must be checked regularly for leaks. To prevent air locks from appearing in the future, you should adhere to the following rules:

Do not allow the engine to overheat or the liquid to boil. The coolant turns into steam, which, under pressure, penetrates into hard-to-reach corners of the cooling system. He is not able to leave them on his own.
Regularly flush the cooling system with water or special fluids. Some drivers advise doing this with Coca-Cola or Sprite drinks. A clean radiator works correctly, so plugs do not form in it.
Correctly fill coolant. Before adding fluid, loosen the clamp and disconnect the fluid supply hose in a car with an injector. In a carburetor engine, disconnect the fluid supply hose from the carburetor fitting. Coolant is poured into the tank to the maximum level. Do this slowly and in a thin stream so that the air from the tank is replaced by water. If there is no level mark, liquid is poured to the top edge of the tank. The filled tank is closed when air bubbles disappear on the surface, then the hoses are connected. After these steps, start the engine and warm it up to operating temperature. After turning on the fan, turn off the engine and check the coolant level. If necessary, add coolant.

Proper coolant changes reduce the risk of air in the system

It is important! The use of high-quality coolant is one of the conditions for preventing air locks. Experienced drivers also advise installing a special filter, which allows you to use even low-quality fluids, but you will have to change it every 3-5 thousand kilometers. Therefore, it is actually more profitable to purchase high-quality liquid.

It is necessary to remove the air lock at the first signs of its appearance in the cooling system. Ignoring the malfunction will lead to expensive vehicle repairs or complete loss of the engine.

Author: Andrey
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How to remove a plug from the system, the second method, detailed instructions

We drive into a viewing hole or a flat surface, again squeeze the handbrake and engage neutral gear.
In this case, the engine does not need to be turned off. It must be heated to a temperature of 90 degrees Celsius so that the thermostat opens and the liquid begins to circulate in a large circle.
We do not open the expansion tank cover.
We turn off the engine.
Then you need to loosen the clamp in the throttle body pipe and remove the pipe. Be extremely careful and careful, wear rubber gloves when working, as the temperature is quite high (90 degrees).
After removing the rubber hose, you need to wait a while until all the air along with the antifreeze comes out.
Now you need to put the pipe back on and tighten the clamp.
At the final stage, we start the engine and test the vehicle. To double-check the system in full, it is advisable to drive it at both low and high speeds.

How to bleed air

There is another method, which is most practical for a unit with a working volume of 1.6 liters. Since in this option air accumulates at a high point. Therefore, the air plug is removed from the throttle assembly.

Accordingly, you will need to use the plastic cover located on the unit itself. You will have to unscrew the cap to add oil. After completing the steps, you will need to remove all the pads, which are held in place using a special rubber seal.

Closing the lid for filling liquid, that is, oil, is quite easy and simple. Once the hose is found, you will need to carefully remove the clamp. Naturally, you should blow into the pipe so that the air comes out completely. Then, you need to quickly insert the hose to avoid air getting inside. By carrying out testing, you can verify the serviceability and functionality of the unit.

How can you remove air from the system?

There are several simple and effective ways to remove air from the heating system of a VAZ-2109, which are also suitable for other cars.

There are three most popular methods; they are based on the principle: oxygen molecules are lighter than water molecules and, therefore, they accumulate at the top, where they are removed.

It is important to fully open the heater valve to the maximum air temperature before starting work.

The first method is universal for cars in which you can unhook the hose, which heats up the throttle assembly or carburetor. These steps can be done on most VAZ cars.

Here the carburetor is the highest point of the engine cooling system. Therefore, this place is most suitable for removing air.

Progress:

Remove both protective covers and anything that prevents access to the heater.
Unscrew the heating hose clamp and remove it from the fitting.
Unscrew the cap of the expansion tank and pump air into it until coolant flows out of the throttle body or pipe.
The moment liquid appears from the hose or fitting, quickly put the hose back in place and screw everything back as it was.

The above-described manipulations will allow you to get rid of the airlock by 99%.

The second method is implemented by removing the pipes that heat the throttle assembly. It is a little similar to the one described above, but it does not require blowing out the tank.

Progress:

Similar to the first method, you need to remove the protective covers and warm up the engine to operating temperature and turn it off.
Leave the cap on the expansion tank, but remove the hose from the fitting.
When the cooling starts, put all the pipes in their places and put everything back together.
One attempt may not be enough and the procedure may not give a positive result; it may need to be repeated a second time.

Important! Remember self-safety measures. The coolant in the circuit may be under pressure and its temperature may be above 85 degrees

If it gets on your skin, it may cause a burn. Try to protect your hands using at least improvised methods. For example, wear cloth gloves with rubber gloves on top.

The third method is the simplest; it does not require disassembling the system. But unfortunately, this method is not as effective as the previous 2.

Progress:

Drive the car uphill so that the top is raised and the radiator cap is the highest point.
Remove the cap from the expansion tank and radiator.
Turn on the ignition and warm up the engine to operating temperature.
Antifreeze will gradually enter the system. It will be necessary to add it from time to time to maintain the desired level.
To increase coolant flow, increase engine speed. In this case, the antifreeze level may drop sharply and should be added urgently. The procedure should be continued until bubbles from the return line stop appearing.

A hot stream from the stove air ducts is a sign that the air has disappeared.

Signs and consequences of an airy system

If the boiler unit is working properly, the supply temperature of the coolant is normal, but the battery cannot cope with heating the room, check the presence of air in the heating system. Air pockets in radiators are a common occurrence; their presence is indicated by uneven heating of the device when the upper part remains cold. Airiness of the battery at first slightly reduces its heat transfer, but if the problem is not solved in time, the accumulated gas will block the path of the coolant and the room will not receive full heating.

Air bubbles interfere with the free movement of the coolant due to the narrowing of the channel, and this provokes the appearance of specific sound effects. Signs of a traffic jam include noise in the pipes, bubbling, and seething. In difficult cases, pipe vibration is also added.

Airing the heating system

Small air bubbles that have not yet formed a plug, but are already actively released from the coolant, turn it into a water-air mixture. It is dangerous for a circulation pump that is not equipped to pump gas. Sliding bearings are installed on the shaft of the pump unit, which must be located in a liquid medium. High air content in the coolant leads to premature wear of elements due to the effect of dry friction.

If you do not bleed air from the heating system, its excess in the coolant can lead to stoppage or breakdown of the circulation pump

. This is dangerous for solid fuel boilers that are not equipped with automation: when the circulation stops, cooled coolant will no longer flow into the water jacket of the boiler. Overheating and boiling of liquid in a confined space threatens to explode if the safety group does not work.

Knowing how to remove air from a heating system, you can deal with air lenses in radiators made from materials prone to corrosion and overgrowth. The air contains carbon dioxide and oxygen, and they contribute to the breakdown of calcium and magnesium salts that are dissolved in water. The reaction proceeds with the release of carbon dioxide. Under the influence of high temperatures, hydrocarbonate compounds form a layer of limescale, and carbon dioxide promotes corrosion of metal surfaces. As a result, the battery deteriorates faster.

Accumulated dirt in the heating system contributes to radiator failure

To avoid unpleasant consequences when starting the heating system at home after the summer break, you should check it for air pockets. If it is airy, quickly take measures to eliminate the problem.

Principles of designing cooling systems

A decrease in the efficiency of the cooling system leads to an increase in the temperature of the pistons and a decrease in the gaps between the piston and the cylinder. Thermal gaps are reduced to zero. The piston touches the cylinder walls, scoring occurs, overheated oil loses its lubricating properties and the oil film breaks. This mode of operation can lead to engine seizure. Overheating is accompanied by uneven expansion of the cylinder head, mounting bolts, engine block, etc. Subsequent destruction of the engine is inevitable: cracks in the cylinder head, deformation of the joint planes of the head and the cylinder block itself, cracks in the valve seats, etc. — it’s unpleasant to even list all this, so it’s better not to let it come to that!

The engine and oil cooling system is designed to prevent such developments, but in order for the system to cope with its tasks, it is necessary to use high-quality coolant (coolant). Low-freezing coolants are called antifreeze - from the English word “antifreeze”. Previously, coolants were prepared based on aqueous solutions of monohydric alcohols, glycols, glycerin and inorganic salts.

Currently, preference is given to monoethylene glycol, a colorless syrupy liquid with a density of approximately 1.112 gcm2 and a boiling point of 198 g. The task of coolant is not only to cool the engine, but also not to boil over the entire operating temperature range of the engine and its components, to have high heat capacity and thermal conductivity, not to foam, not to have a harmful effect on pipes and seals, and to have lubricating and anti-corrosion properties.

In the 70s, antifreeze was produced based on an aqueous solution of monoethylene glycol with a crystallization temperature of 40 degrees. It did not require dilution with water when added to the cooling system. This drug was called TOSOL - after the name of the laboratory “Technology of Organic Synthesis”. Because the name is not patented, then TOSOL is a ready-to-use product, and “antifreeze” is a concentrated solution (although TOSOL is also antifreeze).

Ready-made antifreezes are colored for safety and catchy colors are chosen: blue, green, red. During operation, antifreeze loses its beneficial properties - its anti-corrosion properties decrease, and the tendency to foam increases. The service life of domestic coolants is from 2 to 5 years, imported 5-7 years.

The figure below shows a diagram of the car's cooling system. There is nothing special or complicated in the cooling system and yet...

When the engine starts, the water pump begins to rotate. The pump drive may have its own pulley driven by an accessory belt or driven by the rotation of a timing belt. The cooling system contains an impeller, which rotates and drives the coolant. To quickly warm up the engine, the system is “shorted”, i.e. The thermostat is closed and does not allow fluid to enter the radiator. As the temperature of the coolant rises, the thermostat opens, transferring the system to another state when the coolant passes along a long path - through the radiator of the cooling system (the short path is blocked by the thermostat). Thermostats have different opening characteristics. Typically the opening temperature is marked on the edge. It’s probably not worth explaining the design of the radiator. A fan switch sensor is installed at the bottom of the radiator. If the coolant temperature reaches a certain value, the sensor will close, and because If it is electrically connected to the break in the power supply circuit of the electric fan, then when it is shorted, the cooling system fan should turn on. As the coolant cools, the fan turns off and the thermostat closes the long path to a short one. It's simple, but not very...

This scheme is the basis, but life does not stand still and various manufacturers are improving cooling systems. On some cars you will not find a sensor for turning on the cooling fan, because... The fan is turned on by the engine ECU depending on the readings of the coolant temperature sensor

It is worth paying attention to the situation in which when the ignition is jammed, the cooling system fan immediately turns on. Either the temperature sensor is faulty, or its circuits are damaged, or the engine ECU itself is faulty - it “does not see” the engine temperature and, just in case, immediately turns on the fan

On some cars, special electric valves are installed on the way to the heater, allowing or blocking the path of coolant (BMW, MERCEDES). Such valves sometimes “help” the cooling system fail.

Hisses from the gas tank when opened. Why is this dangerous?

Many car enthusiasts are faced with a phenomenon where opening the fuel tank cap is accompanied by a characteristic hissing sound. After researching this topic, I found a serious discrepancy among users on this issue. Some drivers consider this phenomenon normal and do not pay attention to it, others claim that the system is faulty. Today we will try to understand this difficult issue and understand why hissing when opening the gas tank cap can be dangerous.

Let's start with the reason for this phenomenon. As you know, the fuel in the tank emits vapors (gases)

.
They form especially actively in hot weather. These gases play an important role when starting the engine, creating the required pressure in the system. That is why winter gasoline is supplemented with special additives that make it easier to start the engine in cold weather
.
On the other hand, an excessive amount of vapor indicates a malfunction. To relieve excess pressure, an adsorber is provided in the vehicle design
.

The adsorber consists of a filter element represented by activated carbon. Excess gases are removed from the tank using a special valve. They are then filtered and released into the atmosphere. This decision is due to environmental requirements for vehicles. Now let's get back to our main topic.

I could not find any patterns between the hissing sound when opening the gas tank cap and a specific car model. Some car enthusiasts experience a similar phenomenon immediately after purchasing a new car, while others have never encountered hissing at all. In some cases, drivers note that characteristic sounds are made only when the fuel level in the tank is low

. So what's the logic?

Based on the design features of modern cars, we can say that hissing can be either normal or a sign of a malfunction

Pay attention to the gas tank flap, where there is usually a sticker on the back with operating instructions (the inscription may also be on the lid itself). It often says that you should open the tank slowly to avoid getting fuel on your clothes.

"Remove Slowly") In such a situation, hissing is a normal process associated with the complete sealing of the container.

If nothing like this is written on the sticker or hissing appears, although it has never happened before, it makes sense to think about repairs.

.
Most likely, the problem lies in the excess pressure relief system (the adsorber is clogged, the valve is not working, etc.). Such a problem can cause destruction of the gas tank and increased fuel consumption
(up to 1.5 times!).
I offer you one interesting test.
Drive approximately 10-20 kilometers in normal mode and measure fuel consumption during this period. Then open the cap, which will release excess pressure from the tank. Then we drive the same distance and measure the consumption again. If the difference is significant, the fault is obvious.

Reasons for appearance

There are several reasons why air accumulates in the cooling system channels. An air lock is formed due to:

System leaks. Leaks at the junctions of the pipes lead to the fact that when the liquid flow moves, a vacuum is formed, which sucks air into the system. Gradually the amount of air increases, then it accumulates in one place, forming a plug.
Loss of tightness in the water pump. If the sealing gasket under the pump is damaged, the unit will suck in air during operation.
Violation of technology for replacing or adding antifreeze. If you immediately pour a large amount of liquid, the air in the pipes will not escape and the antifreeze will push air bubbles into the system with its own weight. After starting the engine, the air will gather in one place, interrupting the flow.
Damage to the cylinder head gasket due to overheating. If the resulting breakdown connects the cooling system channel to the atmosphere, the liquid will draw in air from outside. Airing appears if a breakdown connects the channel to the cylinder. In this case, exhaust gases will break into the cooling system, which, in addition to the appearance of an air lock, is accompanied by the bubbling of antifreeze in the expansion tank.

If you suspect that a plug has formed in the cooling system, first make sure that air has occurred. Overheating of the power plant occurs due to jamming of the thermostat, which is also an unpleasant situation.

How do traffic jams appear?

First of all, it’s worth finding out why plugs form in the engine cooling system. Their main reason is the leakage of the system itself. Air bubbles enter the cooling system from outside and clog the system. In this case, it is better to contact a car service specialist. Remember – prevention is always cheaper than cure, and you should never neglect diagnosing your car’s cooling system.

You can try to cope on your own. When diagnosing on your own, you need to find out where the hole through which air enters is located. The most common places where the cooling system is depressurized are presented below:

Connections of tubes, pipes and fittings. There are pressure differences, and when it decreases, excess air enters the system, and if there is a large amount, it forms bubbles, forming plugs and clogging the system.
Expansion tank. If the valve is faulty, it may suck in air at low pressure.
The pump, or more precisely, a violation of its tightness, can also cause the formation of traffic jams. Please note that depressurization of the pump can lead to its complete failure.
Cylinder block gasket. Violation of its tightness can cause not only a decrease in the level of antifreeze, but also a large number of other problems. Its main “symptom” is white smoke from the engine. This means that antifreeze enters the cylinder, and the combustible mixture and gases leak into the cooling system. It is very serious. Urgently go to a car service center.
The radiators themselves are both cooling and cooling (in common parlance - “stove”). In case of defects, they can allow both air into the cooling system and antifreeze in the opposite direction. As a result, plugs appear in the system and the antifreeze level drops. Without creating panic, you need to move towards the service station.

Also quite often problems are associated with the refrigerant used in the cooling system. At that time, when water was poured instead of antifreeze in the summer, it happened that the new refrigerant was mixed with the old one, which was not completely removed from the system during flushing. This happens even now, when replacing one antifreeze with another.

Therefore, when flushing the cooling system, do it carefully and fill in antifreeze as stated in the instructions for its use to prevent bubbles from mixing in the system.

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Often the problem is with the refrigerant itself. Antifreeze produced by the unknown Vasya Pupkin is, of course, cheaper. However, it not only cools the engine worse, but can also delaminate and clog the cooling system. There is a way out - installing an antifreeze filter, but they have to be changed quite often, and replacing a filter is certainly more expensive than the most expensive refrigerant. So it’s better not to skimp on coolant.

There are cases when, even if good antifreeze was added, the cooling system became clogged with air. The new antifreeze still differs from the used one (albeit slightly) both in composition and temperature. In addition, bubbles form when mixed. In general, only drivers of air-cooled cars are fully insured against this misfortune.

This will reduce the risk of an air lock.

If you adhere to the rules of car operation, you can significantly reduce the risk of an air lock in the car. These recommendations look like this:

compliance with the requirements of the service book for undergoing technical maintenance;
checking the coolant level at least once a month;
Fill only with recommended, high-quality coolant. Very often, if low-quality coolant is used, the system becomes airy.

Bottom line

It's time to take stock. The cooling system in every car plays a major role in providing the necessary cooling and maintaining the desired temperature of the internal combustion engine, and is also responsible for heating the interior. If you carry out scheduled maintenance on time and monitor the coolant level, then problems with the engine will not arise. After all, if airing in the system is not noticed and eliminated in time, this can lead to serious problems, in some cases to a major overhaul of the internal combustion engine.

Prevention of air pollution causing engine overheating

To eliminate cooling problems, you need to follow the recommendations:

periodically check the antifreeze level;
use only tested coolant (coolant);
when replacing, it is recommended to pay attention to the color of the coolant and buy a similar new one;
problems that arise must be eliminated immediately after they appear, without waiting for the situation to worsen.

The main recommendation of experts is to carry out maintenance by trusted technicians and not to pour water into the system.

Why is aeration dangerous?

An air lock present in the stove and cooling system of the VAZ-2109 will cause you a lot of trouble. Since the motor will warm up unevenly and there is a high probability of overheating due to poor cooling. The presence of air in the circuit prevents the coolant from circulating, which interferes with the heat extraction of antifreeze from the engine. An air lock also prevents the coolant from penetrating into the radiator, thereby causing the engine to overheat.
Airing can also occur due to a car's heater not working for a long time. In this case, the antifreeze does not penetrate the heater radiator and remains cool, and the air does not heat up either.

Why are air locks dangerous?

Air getting inside a water heating system is a very common phenomenon. And you should respond to it immediately. While some air in the system may not seem dangerous, it can often cause more serious problems.

And sometimes airiness of the radiator or pipes makes it possible to identify breakdowns or flaws in the installation of the heating system.

The presence of air locks usually manifests itself in the form of uneven heating of individual system elements, for example, radiators.

If the device is only partially filled with coolant, its operation can hardly be called effective, since the room does not receive part of the thermal energy, i.e. doesn't warm up.

If the top of the heating radiator remains cold and only the bottom warms up, the device is most likely airy, you need to bleed the air

If air has accumulated in the pipes, it prevents the normal flow of coolant. As a result, the operation of the heating system may be accompanied by quite loud and unpleasant noise.

Sometimes part of the system begins to vibrate. The presence of air in the circuit causes the activation of various chemical processes, for example, it can cause the decomposition of calcium and magnesium bicarbonate compounds.

This leads to the formation of carbon dioxide, which disrupts the acid-base balance of the coolant. Increased acidity increases the corrosive effect on heating system elements, which can lead to a noticeable reduction in their service life.

In addition, chemical processes occurring under the influence of high temperatures cause the deposition of limestone deposits on the walls of pipes and radiators, creating a dense coating.

As a result, the pipe clearance decreases, the characteristics of the heating system change, and it operates with less efficiency. A large amount of limescale can completely clog the pipes; they will have to be cleaned or even completely replaced.

The presence of air in an autonomous heating system may indicate processes that contribute to the appearance of sediment and clogging of the heating circuit pipes

If a circulation pump is included in the heating circuit, the presence of air in the system can adversely affect its operation. The bearings of this device are designed to withstand constant exposure to an aquatic environment. If air gets into the pump, the bearing will run dry, causing it to overheat and fail.

Possible consequences

If a plug in the cooling system has been diagnosed, you should not put off removing it for too long. Impaired coolant circulation will very soon lead to dire consequences. Engine cooling efficiency drops significantly. Operation at high temperatures leads to accelerated wear of unit components. In extreme cases, naturally, there will be deformation and jamming. It will no longer be possible to do without major repairs, and this pleasure is extremely expensive.

The second is problems with the stove. Its functioning directly depends on the complete circulation of coolant. In the summer, a non-working stove will not create any inconvenience, but in winter it will become a real test for the driver. Also, operating a car with an air lock will lead to increased fuel consumption and damage to individual sensors. If you really want to save money, renovate now!