We are talking about the engine internal combustion. By title it can be seen that the fuel is combustion inside the engine. It turns out heat that warms the motor. For the engine, the optimal temperature is needed at which it works fine. To create and maintain such a given mode, the cooling system is used in many engines, which includes the cooling fluid circulation in the engine.

The system itself complicates the manufacturing process, making it more energy-intensive, which leads to the appreciation of the entire structure. During operation, it is required to conduct regular observation, troubleshooting and repair. Therefore, the cooling system is striving to make the easiest. All systems can be divided into three types:

• air;
• liquid;
• combined.

Using air

The air system is the simplest and cheap, mostly does not require additional equipment and supervision. Two circulation methods are used:

• natural;
• forced.

The natural way is widely used on high-speed and light moving vehicles, for example, in airplanes, which, as a rule, fly in colder atmospheric layers.

The engine is cooled by air, which is injected with screw. To easy vehicles You can attribute motorcycles and all kinds of models. The engine capacity of such structures is small, natural blowing, basically enough. To increase the heat transfer, the cylinders are made from the engine and are supplied with ribs.

A negative feature of such cooling is the absence of the ability to adjust the engine temperature. In cold weather, it takes a lot of time to warm it, and it is necessary to join the engine so that it is cooled.

This problem is partially solved by a compulsory way. It is used in engines that are installed inpatient. In this case, the air flow coming from the fan is directed to the engine. This thread can be controlled by changing the speed of rotation of the fan.

Eating fluid

In order for the cooling system to be more adjustable and efficient, the liquid cooler is used. In addition, the Tosol movement circuit in the cooling system has two circles: large and small, which also contributes to the uniform temperature. In this capacity used water before. In contrast to air, the water is the best heat transfer, which increases efficiency. Used system can be:

• closed;
• unlocked.

When using the first system, the liquid circulates along a closed chain. Moves through pipes or hoses of gravity or thanks to the water pump. Heating from the operating engine, it expands, creating a pressure exceeding atmospheric. Therefore, the boiling point reaches 110-120 degrees. For cooling, a heat exchanger is used, which, in turn, is cooled by air flow. To adjust the temperature (coat), the speed of air passing through the heat exchanger is changed. This can be done, opening and closing the blinds or changing the flow rate of the air. Used in powerful engines.

An unlocked system is used where there is no shortage of water - this is a floating. Water comes from the reservoir and with the help of the pump is transmitted to the engine. After cooling the engine, it is thrown out.

The advantage is that it is not necessary to install a heat exchanger and a fan for cooling it.

The work of the combined scheme

Such a system is mainly used in cars and some motorcycles. It includes both liquid and aerial cooling. In the cylinder block, windows are made by which the water flows and heats up.

In order not to disturb the natural movement of the heated fluid, it is fed to the bottom edge of the cylinder, then it rises to the head and goes out. After that, the movement continues on the tube to the radiator's top tank. Running down the tubes of the radiator, the liquid is cooled and the tube is suitable for a water pump, also a member of the pump. From the pump on the tube passes into the lower edge of the cylinder block, and the coolant movement circuit in the engine is closed.

IN winter timeAnd when the motor has not yet heated, there is no need to cool the motor.

To disable the radiator for this time, use the thermostat. Thus, it is a regulator to determine the large and small circle of the cooling system. It is located at the outlet of the coolant from the motor. The thermostat is designed in such a way that with low cooling fluid temperatures overlaps access to the radiator, forming a small circle of engine cooling.

Elements included in the system

The combined circuit of the closed type includes the system of heating the machine interior. Based on this, you can draw up the following list of elements included in the cooling system:

• radiators (one for cooling, another for heating);
• fans;
• water pump (pump);
• thermostat;
• temperature sensor.

The radiator performs a major role in the cooling system. It is made of two tanks, which are combined with a plurality of brass welded or elongated tubes. From aluminum tubes make less frequently, as their strength is lower. The tubes can be straight or tape, cross-section ellipse. Due to this structure, they are easier to withstand the pressure of the frozen liquid. To increase the heat transfer area, the tubes pass through the package of plates. There is a crane for draining liquid in the lower tank. The top tank is a neck or nozzle leading to an expansion tank. Closed by a plug, inside which are located intake and exhaust valve.

On the lateral side of the radiator there is a temperature sensor indicating the temperature of the coolant. The center establishes a fan for blowing the radiator. Drive he can receive three ways:

1. Directly from the crankshaft.
2. Through the coupling.
3. From the electric motor.

Water centrifugal pump drives fluid throughout the system. Fucked directly on the crankshaft. With a high motor power, oil cooling, installing an oil radiator on the main one.

The cheapest liquid is water, especially if it is soft. It has good heat capacity, has a low viscosity, which allows it to leak through small holes. However, it strongly causes corrosion and freezes at relatively high temperatures, so it is replaced with Tosol.

IN soviet time There was an institute that was engaged in the development of cooling liquids. The combination of all liquids struggling with freezing, icing is called antifreeze (translated as "against freezing"). These include an aqueous solution of ethylene glycol, less often propylene glycol, which is non-toxic, but significantly more expensive.

Antifreeze not only freeze at lower temperatures, but also less expand during freezing. For example, water is expanding by 9%, and 40% an aqueous solution of ethylene glycol is only 1.5%. The freezing process is also different. Water during freezing turns into a solid monolith, and the solution of ethylene glycol is crystallized, without harming mechanisms.

Additives that are included in antifreeze are aimed at combating corrosion, lubricate foaming parts, fight foam. It is also important that they also have increased the boiling point, which has a beneficial effect on the motor.

With all the advantages of ethylene glycol antifreeze have cons. The main one is high toxicity. For a person weighing 70 kg, 140 milliliters are enough to lead to a fatal outcome. Poison is not only fluid itself, but also its pairs. Even a small leakage in the heating radiator can lead to severe consequences. For timely detection of malfunction, such antifreeze has fluorescent properties.

Another disadvantage is a great expansion coefficient. For new cars, this is not a problem, they already have for this case expansion tank, But for older without refinement it will be difficult. In the hot state, antifreeze will be thrown away, and when it will cool, the level will fall greatly. There is another difficulty, it is much harder to cope with it.

Antifreeze worse transfers heat by about 15-20%. In hot weather, he simply won't cope with his work, and the motor can overheat.

The shelf life of ethylene glycol is limited to 2 to 3 years, at elevated temperatures, the term is strongly reduced, and when the temperature of 105 degrees exceeds, the additives that lubricate the engine parts are rapidly destroyed. Silicate antifreeze uses to improve the quality. In the United States and Japan, phosphate antifreeze are used, but for Europe, due to increased rigidity of water, they are unsuitable.

Strictly speaking, the term "liquid cooling" is not fully correct, since the fluid in the cooling system is only an intermediate coolant, penetrating the walls of the cylinder block wall. The role of the discharge agent in the system plays air, blowing the radiator, so cooling modern car It is correct to call hybrid.

Device of the liquid cooling system

The liquid engine cooling system consists of several elements. The most complicated is called the "cooling shirt". This is an extensive network of channels in the thickness of the cylinder block and. In addition to the shirt in the system enters the radiator of the cooling system, the expansion tank, water pump, thermostat, metal and rubber connecting nozzles, sensors and control devices.

Propylene glycol - Base of coolant (antifreeze) and approved by veterinary doctors Food additive for dietary dogs

The system is constructed on the principle of forced circulation, which the water pump provides. Due to the constant outflow of the heated fluid, the engine is cooled uniformly. This explains the use of the system in the overwhelming majority of modern cars.

After passing through the channels in the walls of the block, the liquid heats up and falls into the radiator, where the air flow is cooled. When the car moves, it is quite natural enough to cool, and when the car is worthwhile, blowing occurs due to the electric fan, which turns on the signal from the temperature sensor.

Details about key elements of water cooling

Cooling radiator

The radiator is a panel of small-diameter metal tubes, covered to increase the heat transfer area by aluminum or copper "plumage". In essence, plumage, this is a multiple metal tape. The total total ribbon area is large enough, which means that there can be enough heat into the atmosphere per unit of time.

The most vulnerable element of the engine design is a turbocharger (turbine) operating on extremely high revolutions. When overheating, the destruction of the impeller and shaft bearings is almost inevitable

Thus, the warm-up liquid inside the radiator circulates immediately on all numerous thin tubes and is cooled quite intensively. In the lid of the filling neck of the radiator is provided safety valve, Distributing pairs and excess fluid expanding when heated.

Depending on the mode the work of the DVS The cycle of the coolant movement in the system may vary. The volume of fluid circulating in each circle directly depends on the extent to which the main and additional thermostat valves are open. This scheme provides automatic support for the optimal temperature mode of the engine.

Advantages and disadvantages of the liquid cooling system

The main advantage of the liquid cooling is that the engine cooling occurs evenly than in the case of blowing the air flow unit. This is explained by the greater heat capacity of the coolant compared to air.

The liquid cooling system allows to significantly reduce the noise from the working engine due to the greater the thickness of the block walls.

The system inertia does not allow the engine quickly after turning off. Preheat liquid of the car and for preheating combustible mixture.

Along with this, the liquid cooling system has a number of disadvantages.

The main disadvantage is the complexity of the system and that it works under pressure after heating the fluid. Pressure fluid places increased requirements for the tightness of all compounds. The situation is complicated by the fact that the operation of the system implies a constant repeat of the cycle "Heating - cooling". It is harmful for compounds and rubber pipes. When heated, the rubber is expanding, and then compressed when cooled, which becomes the causes.

In addition, the complexity and a large number of elements by itself serves as a potential cause of "technogenic disasters", accompanied by the "boiling" of the engine in case of failure of one of the key parts, for example, the thermostat.

Recall once again a little about this cooling system.

IN liquid cooling system Special cooling fluids are used - antifreeze different markshaving a thickening temperature - 40 ° C and below. Antifreeze contain anti-corrosion and anti-speaking additives, excluding scale formation. They are very poisonous and demand cautious. Compared to water, antifreeze has a smaller heat capacity and therefore remove heat from the walls of the engine cylinders is less intensively.

So, when cooling with antifreeze, the temperature of the walls of cylinders by 15 ... 20 ° C is higher than when cooling with water. It accelerates the engine heating and reduces the wear of the cylinders, but in the summer it can lead to engine overheating.

The optimal temperature mode of the engine with a liquid cooling system is considered to be such at which the temperature of the coolant in the engine is 80 ... 100 ° C on all modes of engine operation.

In car engines applied closed (hermetic) liquid cooling system from forced circulation Coolant.

The inner cavity of the cooling cooling system does not have a permanent connection with the environment, and the connection is carried out through special valves (at a certain pressure or vacuum), located in the radiator tubes or the expansion tank of the system. The coolant in such a system boils at 110 ... 120 ° C. Forced coolant circulation in the system is provided by a liquid pump.

Engine cooling system consists of:

• shirt cooling head and cylinder block;
• radiator;
• pump;
• thermostat;
• fan;
• expansion tank;
• connecting pipes and drain cranes.

In addition, the cooling system includes a car body salon.

Principle of operation of the cooling system

I suggest to consider first principal scheme cooling systems.

1 - heater; 2 - engine; 3 - thermostat; 4 - pump; 5 - radiator; 6 - plug; 7 - fan; 8 - expansion tank;
A - a small circle of circulation (the thermostat is closed);
A + b - a large circle circulation (the thermostat is open)

The circulation of fluid in the cooling system is carried out in two circles:

1. Small circle - liquid circulates when starting a cold engine, providing it fast warming.

2. Big circle - The movement circulates when the engine is heated.

If it is easier to speak, then a small circle is circulation of coolant without a radiator, and a large circle - circulation of coolant through the radiator.

The cooling system device differ in its device depending on the car model, however, the principle of operation is one.

The principle of operation of this system can be seen in the following videos:

I propose to disassemble the system of the system on the sequence of work. So, the start of the cooling system occurs when the heart is started in this system - the liquid pump.

1. Liquid pump (Water Pump)

The liquid pump provides forced fluid circulation in the engine cooling system. On the engines of cars apply paddle pumps of centrifugal type.

Search for our liquid pump or water Pompe It follows on the front of the engine (the front part of this one, which is closer to the radiator and where the belt / chain is located).

Liquid pump connected with a belt with crankshaft and generator. Therefore, to find our pump just find the crankshaft and find the generator. We will talk about the generator later, but so far only show what you need to look. The generator looks like a cylinder attached to the engine housing:

1 - generator; 2 - liquid pump; 3 - crankshaft

So, the location was understood. Now let's look at its device. Recall that the device of the entire system and its details are different, but the principle of operation of this system is the same.

1 - pump cover;2 - Stubborn sealing ring of the gland.
3 gland; 4 - pump roller bearing.
5 - hub pulley fan;6 - locking screw.
7 - pump roller;8 - pump housing;9 - Pump impeller.
10 - receiving nozzle.

The pump work is as follows: the pump drive is carried out from the crankshaft through the belt. The belt twists the pump pulley, rotating the hub of the pump pulley (5). He in turn leads to rotation of the pump shaft (7), at the end of which the impeller is located (9). The coolant enters the pump housing (8) through the receiving nozzle (10), and the impeller moves it into the cooling shirt (through the window in the case, visible in the figure, the direction of movement from the pump is shown by the arrow).

Thus, the pump has a drive from the crankshaft, the liquid enters it through the receiving nozzle and goes into the cooling shirt.

Liquid pump work in this video (1:48):

Let's see now, how do liquid go to the pump? And the fluid comes through a very important part - the thermostat. It is the thermostat that is responsible for the temperature regime.

2. THERMOSTAT (THERMOSTAT)

The thermostat automatically adjusts the water temperature to accelerate the engine warming after starting. It is the work of the thermostat that determines how the coolant (large or small) will go.

This unit looks like this in reality:

The principle of operation of the thermostat Very simple: The thermostat has a sensitive element, inside of which the solid filler is located. At a certain temperature, it starts to melt and opens the main valve, and the optional on the contrary is closed.

Thermostat device:

1, 6, 11 - nozzles; 2, 8 - valves; 3, 7 - springs; 4 - cylinder; 5 - diaphragm; 9 - rod; 10 - filler

Thermostat work is simple, you can see it here:

The thermostat has two inlet nozzles 1 and 11, outlet nozzle 6, two valves (main 8, optional 2) and a sensitive element. The thermostat is installed before entering the coolant pump and connects to it through the nozzle 6.

Compound:

Throughpipe 1. Connect fromengine cooling shirt,

Through pipe 11. - With Lower disclosure Bulk radiator.

The sensitive element of the thermostat consists of a cylinder 4, rubber diaphragm of 5 and stock 9. Inside the cylinder between its wall and rubber diaphragm there is a solid filler 10 (fine-crystalline wax) with a high volume extension coefficient.

The main valve 8 of the thermostat with spring 7 begins to open at a coolant temperature of more than 80 ° C. At a temperature of less than 80 ° C, the main valve closes the yield of the fluid from the radiator, and it comes from the engine to the pump, passing through the opening additional valve 2 of the thermostat with spring 3.

As an increase in the temperature of the coolant more than 80 ° C in the sensitive element, a solid filler melts, and its volume increases. As a result, the rod 9 comes out of the cylinder 4, and the balloon moves up. An additional valve 2 begins to close and at a temperature of more than 94 ° C overlaps the coolant pass from the engine to the pump. The main valve 8 in this case opens completely, and the coolant circulates through the radiator.

The valve operation is clear and clearly shown in the figure below:

A - small circle, the primary valve is closed, bypass - closed. B - a large circle, the main valve is open, the bypass - closed.

1 - inlet nozzle (from the radiator); 2 - primary valve;
3 - thermostat housing; 4 - bypass valve.
5 - nozzle of the bypass hose.
6 - Cooling fluid supply pipe into the pump.
7 - thermostat cover; 8 - piston.

So, we dealt with a small circle. Disassembled the device and thermostat, connected. And now let's get to the big circle and the key element of the big circle - the radiator.

3. Radiator (Radiator / Cooler)

Radiator Provides the heat of the cooling fluid heat in environment. On the passenger cars Tubular plate radiators are used.

So, there are 2 types of radiators: collapsible and not collapsible.

The bottom is presented to their description:

I want to say again about the expansion tank (Expansion Tank)

Next to the radiator or the fan is installed on it. Let's now turn to the device of this fan itself.

4. Fan (FAN)

The fan increases the speed and amount of air passing through the radiator. On the engines of cars, four- and hexadener fans are installed.

If a mechanical fan is used,

The fan includes six or four blades (3), glued to the Cross (2). The latter is brought to the pulley of the liquid pump (1), which is driven by the crankshaft using the belt transmission (5).

As we previously talked, the generator (4) also enters the engagement.

If an electric fan is applied,

that fan consists of a 6 and fan motor 5. Fan - four-blade, attached to the motor shaft. The blades on the hub of the fan are located unevenly and at an angle to the plane of its rotation. This increases the flow of the fan and reduces the noise of its operation. For more efficient operation, the electric fan is placed in a casing 7, which is attached to the radiator. Electristant attached to the casing on three rubber bushings. The electric fan is turned on and off automatically sensor 3, depending on the coolant temperature.

So, let's summarize. Let's not alone and summarize on some picture. Do not focus on concrete device, But the principle of work should be understood, for it is the same in all systems, no matter how their device would not differ.

When starting the engine, the crankshaft begins to rotate. Through the belt transmission (I will remind you that it also contains the generator) is transmitted rotation to the pulley of the liquid pump (13). It leads to rotation shaft with an impeller inside the body of the liquid pump (16). The coolant enters the engine cooling shirt (7). Next, through the outlet (4), the coolant returns to the liquid pump through the thermostat (18). At this time, the thermostat is opened by a bypass valve, but closed the main one. Therefore, the fluid circulates through the engine shirt without the participation of the radiator (9). It provides quick engine warming. After the coolant is heated, the main thermostat valve opens and the bypass valve is closed. Now the fluid can not flow through the torus of the thermostat (3) and is forced to flow through the supply nozzle (5) into the radiator (9). There, the liquid is cooled and arrives back into the liquid pump (16) through the thermostat (18).

It is worth noting that some of the coolant comes from the engine cooling shirt into the heater through the nozzle 2 and returns from the heater through the nozzle 1. But we will talk about it in the next chapter.

I hope now the system will become understandable for you. After reading this article, I hope it will be possible to navigate in another cooling system, which realized the principle of operation of this.

I propose to read the same with the following article:

Since we affected the heating system, the next my article will be about this system.

Cooling system

The cooling system is intendedto maintain normal thermal regime Engine.

When the engine is running, the temperature in the engine cylinders periodically rises above 2000 degrees, and the average temperature is 800-900 ° C!

If you do not distinguish heat from the engine, then after a few tens of seconds after the launch it will not be cold, but hopelessly hot. Next time you can run your cold Engine Only after it overhaul.

The cooling system is necessary for heat removal from the mechanisms and parts of the engine, but it is only half of its purpose, however, a large half.

To ensure a normal workflow, it is also important to accelerate the warm engine warming. And this is the second part of the cooling system.

As a rule, there is a liquid cooling system, a closed type, with forced fluid circulation and an expansion tank (Fig. 29).

The cooling system consists of:

shirts cooling block and head of the cylinder block,

centrifugal pump,

thermostat

radiator with an expansion tank,

fan,

connecting nozzles and hoses.

In fig. 29 You can easily distinguish two circle circulation of coolant.

Fig. 29. Engine cooling system scheme:1 - radiator; 2 - nozzle for circulating coolant; 3 - expansion tank; 4 - thermostat; 5 - water pump; 6 - shirt cooling block of cylinders; 7 - Block head cooling shirt; 8 - heater radiator with an electric fan; 9 - the heater radiator crane; 10 – cork for draining coolant from the block; 11 is a plug for draining coolant from the radiator; 12 - fan

The small circle of circulation (red arrows) is used for early warm-up warm engine. And when blue join the red arrows, the already heated liquid begins to circulate in a large circle, coolant in the radiator. Manages this process automatic device – thermostat.

To control the operation of the cooling system, on the instrument panel there is a coolant temperature pointer (see Fig. 67). The normal temperature of the coolant during engine operation should be within 80-90 ° C.

Engine cooling shirtit consists of a plurality of channels in the block and head of the cylinder block, which circulates the coolant.

Centrifugal type pumpmakes the liquid to move along the engine cooling shirt and the entire system. The pump is driven by the belt transmission from the pulley of the crankshaft of the engine. The belt tension is regulated by the deviation of the generator body (see Fig. 63 a) or tensioner roller Drive distribution Vala. Engine (see Fig. 11 b).

Thermostatdesigned to maintain a constant optimal thermal mode of the engine. When starting a cold engine, the thermostat is closed, and the entire liquid circulates only in a small circle (Fig. 29 A) for the early warm-up. When the temperature in the cooling system rises above 80-85 ° C, the thermostat automatically opens and part of the fluid enters the radiator for cooling. At high temperatures, the thermostat opens completely, and now the entire hot liquid is sent by a large circle for its active cooling.

Radiatorit serves to cool the fluid passing through it due to air flow, which is created when the vehicle is moving or using the fan. The radiator has many tubes and partitions that form a large surface area of \u200b\u200bthe cooling.

Expansion tankwe are necessary to compensate for changes in the volume and pressure of the coolant when it is heated and cooling.

Fanit is intended for a forced increase in air flow passing through a radiator of a moving car, as well as to create a stream of air in the case when the car costs without moving with the engine.

Two types of fans are used: permanently enabled, with a belt drive from a crankshaft pulley and an electric fan, which turns on automatically when the coolant temperature reaches approximately 100 ° C.

Pipes and hosesserve to connect cooling shirt with thermostat, pump, radiator and expansion tank.

The engine cooling system is also included salon heater.Hot cooling fluid passes through radiator heaterand heats the air supplied to the interior of the car.

Air temperature in the cabin is regulated by special cranewith which the driver increases or reduces the flow of fluid passing through the heater radiator.

Basic cooling system malfunctions

Bending coolantit may appear as a result of damage to the radiator, hoses, sealing gaskets and seals.

To eliminate the fault, you must tighten the hose mounting clamps and tubes, and damaged details Replace new ones. In case of damage to the radiator tubes, you can try to patch down holes and cracks, but, as a rule, everything ends with the replacement of the radiator.

Engine overheatingit occurs because of the insufficient level of coolant, weak tension of the fan belt, clogging of the radiator tubes, as well as when thermostat malfunction.

To eliminate the engine overheating, restore the fluid level in the cooling system, adjust the fan belt tension, rinse the radiator, replace the thermostat.

Often, the engine overheating also occurs with the serviceable elements of the cooling system, when the machine moves at low speed and large loads on the engine. This happens when driving in heavy road conditions, such as country roads and all boring city "traffic jams". In these cases, it is worth thinking about the engine of your car, and about yourself too, arranging periodic, at least short-term "respite."

Be careful behind the wheel and do not allow the emergency mode of operation of the engine! Remember that even one-time overheating of the engine disrupts the structure of the metal, while the life expectancy of the "heart" of the car is significantly reduced.

Operation of the cooling system

When operating a car, it should be periodically peeled under the hood. A timely noted malfunction in the cooling system will allow you to avoid engine overhaul.

If a cooling fluid level in the expansion tankit has dropped or the liquid is absent at all, then it is necessary to add it to the beginning, and then it should be sorted out (independently or with a specialist), where it is done.

In the process of operation of the engine, the liquid is heated to a temperature close to the boiling point. This means that the water, which is part of the coolant, will gradually evaporate.

If half a year daily exploitation The car level in the tank dropped a bit, then this is normal. But if yesterday was a complete tank, and today it is only on the bottom, then you need to look for a place of leakage of coolant.

The leakage of fluid from the system can be easily determined on dark spots on asphalt or snow after more or less long-lasting parking. Opening the hood, you can easily find a leakage place, comparing wet traces on the asphalt with the location of the cooling system elements under the hood.

The fluid level in the tank must be monitored at least once a week. If the level has decreased noticeably, then it is necessary to determine and eliminate the reason for its decline. In other words, the cooling system must be put in order, otherwise the engine can seriously "get sick" and demand "hospitalization".

Almost all domestic cars A special low-gas fluid with the title is used as a coolant Tosol A-40.Numeral 40 shows a negative temperature at which the liquid begins to freeze (crystallize). Under the conditions of the Far North applied Tosol A-65 , and accordingly, it starts to freeze at a temperature of minus 65 ° C.

Tosol is a mixture of water with ethylene glycol and additives. Such a solution combines a lot of advantages. First, it begins to freeze it only after the driver itself (joke), and secondly, Tosol has anti-corrosion, antitrusive properties and practically does not give deposits in the form of ordinary scale, since its composition includes clean distilled water . therefore you can only add distilled water into the cooling system.

When operating a car you need control not only the tension, but also the state of the water pump drive belt,since his opening on the road is always unpleasant. It is recommended to have a spare strap in the road set. If you don't, then someone from good people will help you change it.

Cooling fluid can boil and lead to engine breakdown in the event that failed fan electric drive sensor.If the electric fan has not received the command to turn on, the liquid continues to heat up, approaching the boiling point, without having a comprehensive assistance.

But at the driver before his eyes there is a device with an arrow and a red sector! Moreover, almost always when the fan is turned on, it feels small additional noise. There would be a desire to control, and the ways will always be found.

If on the way (and more often in the "plug") you noticed that the temperature of the coolant approaches the critical, and the fan works, then in this case there is a way out. It is necessary to include an additional radiator in the operation of the cooling system - the radiator of the cabin heater. Fully open the driver's crane, all turns include the heater fan, lower the glass of the doors and "pull" to the house or to the nearest car service. But at the same time, continue to closely monitor the engine temperature pointer. If she still goes into the red zone, stop immediately, open the hood and "cool".

Over time, can deliver trouble thermostat,if it stops letting the liquid in a large circle of circulation. Determine whether the thermostat works is not difficult. The radiator should not be heated (determined by hand) until the coolant temperature pointer arrow does not reach the middle position (the thermostat is closed). Later, the hot liquid will start entering the radiator, quickly heating it, which indicates the timely opening of the thermostat valve. If the radiator continues to remain cold, then there are two ways. Touch the body of the thermostat, maybe it will still open, or immediately, morally and financially, prepare for its replacement.

Immediately "give up" mechanics if on oil probe You will see the droplets of the liquid that fell from the cooling system into the lubrication system. It means that damaged cylinder head gasketand the coolant is seeping into the engine crankcase pallet. If you continue the operation of the engine with oil, half consisting of toosol, then wear engine parts acquires catastrophic speed.

Water pump bearingit does not break "suddenly." At first there will be a specific whistling sound from under the hood, and if the driver "thinks about the future", then the bearing will be replaced in a timely manner. Otherwise, it will still have to change it, but already with the consequence of finding the airport or on a business meeting, because of the "suddenly" broken car.

Each drivers should know and remember that on the hot engine, the cooling system is in a state of high pressure!

If the engine of your car overheated and "boiled", then, of course, it is necessary to stop and open the car hood, but you can not open a radiator cork or an expansion tank. To accelerate the engine cooling process, this will not give anything practically, and it is possible to get strongest burns.

Everyone knows than it turns around for a smartly dressed guests ineptly open bottle of champagne. Everything is much more serious in the car. If you quickly and mindlessly open the cork of the hot radiator, then the fountain will fly out from there, but no longer wines, and boiling toosol! In this case, not only the driver can suffer, but also the pedestrians. Therefore, if you ever have to open a radiator cork or an expansion tank, then it is pre-taking precautions and do it slowly.

To maintain the optimal engine temperature, a cooling system is required.

The average temperature of the engine 800 - 900 ° C, with active work reaches 2000 ° C. But periodically it is necessary to remove heat from the engine. If this is not done, the engine can overheat.

But the cooling system not only cools the engine, but also participates in its heating when it is cold.

Most cars have a closed-type liquid cooling system with forced fluid circulation and an expansion tank (Figure 7.1). Fig. 7.1. Motor cooling system diagram) Small circulation circulation b) large circle circulation 1 - radiator; 2 - nozzle for circulating coolant; 3 - expansion tank; 4 - thermostat; 5 - water pump; 6 - shirt cooling block of cylinders; 7 - Block head cooling shirt; 8 - heater radiator with an electric fan; 9 - the heater radiator crane; 10 - plug for draining coolant from the block; 11 is a plug for draining coolant from the radiator; 12 - fan

The elements of the cooling system are:
• shirts cooling block and head of the cylinder block,
• centrifugal pump,
• thermostat
• radiator with an expansion tank,
• fan,
• connecting nozzles and hoses.

Under the guidance of the thermostat, 2 circles circles perform their functions (Figure 7.1). The small circle performs the engine heating function. After heating, the fluid begins to circulate along a large circle and cooled in the radiator. The normal temperature of the coolant is 80-90 ° C.

Engine cooling shirt is the channels in the block and head of the cylinder block. On these channels circulate coolant.

The centrifugal type pump contributes to the movement of the liquid on the shirt and throughout the engine system. Makes the liquid to move along the engine cooling shirt and the entire system.

The thermostat is mechanisms supporting the optimal thermal engine mode. When a cold engine is launched, the thermostat is closed and the liquid moves along a small circle. When the fluid temperature exceeds 80-85 ° C, the thermostat opens, the liquid begins to circulate by a large circle, falling into the radiator and cooling.

The radiator is a plurality of tubes forming a large cooling surface. Liquid is cooled here and cooled.

Expansion tank. With it, the volume of fluid compensation occurs when it is heated and cooled. The fan increases the air flow into the radiator, with which

liquid is waiting.

Nozzles and hoses are a cooler with a thermostat shirt with a thermostat, a pump, a radiator and an expansion tank.

Major cooling system malfunctions.

Leak coolant. Reason: damage to the radiator, hoses, sealing gaskets and glands. Methods of elimination: tighten the hose mounting clamps and tubes, replace damaged items to new ones.

Engine overheating. Cause: Insufficient coolant level, weak fan belt tension, clogging of radiator tubes, thermostat malfunction. Remedy methods: Restore fluid level in the cooling system, adjust the fan belt tension, rinse the radiator, replace the thermostat.