Normal functioning power plant car is possible only at a certain temperature. For most cars, the optimal temperature range is 80-90 degrees. C. At a lower rate, mixture formation in the cylinders worsens, and high temperature leads to expansion of the metal, which can cause jamming of the components.

General arrangement of the cooling system

To keep the temperature of the power plant in the optimal range, a cooling system is included in the design of the motor. It is thanks to it that heat is removed from the most heated elements - the cylinders.

Types of cooling systems

Total on engines internal combustion two types of cooling are used - air and liquid.

Air cooling system, its design, disadvantages

Device air system engine cooling

Due to a number of shortcomings, road transport the air system is not widespread, although structurally it is much simpler than the liquid one. Its main element is the cooling fins on the cylinders.

The heat released from the cylinders was distributed to these fins, and the air flow passing through them carried it out. To create a flow, the system design could additionally include a turbine - a special impeller driven by crankshaft and a sleeve with which the generated air flow was directed to the cylinders. This is the whole structure of the air system.

The air system is practically not used in road transport because:

• adjustment impossible temperature regime (in winter the motor did not reach the required temperature, and in summer it overheated very quickly);
• to ensure an even distribution of the air flow, each cylinder stood separately;
• when parked with the engine running, even with a turbine, the air flow is very weak, which leads to rapid overheating;
• it is impossible to arrange interior heating.

Due to these shortcomings, the air system is not used on cars, although there were still isolated cases - ZAZ-968 "Zaporozhets" had just such a cooling system. But it is widely used in motor vehicles and equipment equipped with 2-stroke motors (chainsaws, brushcutters, walk-behind tractors, etc.).

Video: Engine cooling system. Device and principle of operation

Device, design, principle of operation

Liquid cooling system

The advantage of a liquid cooling system is precisely the ability to maintain the temperature in a given range, therefore it is better than an air one. But the design of this system is much more complicated.

It includes:

1. Cooling jacket
2. Water pump
3. Thermostat
4. Radiators
5. Connecting pipes
6. Fan

In this case, the main working element of such a system is special liquid -, with the help of which heat is removed. Previously, ordinary water was used instead, but due to the low temperature threshold of freezing and the formation of scale, water was gradually abandoned.

1. Cooling jacket

Cooling jacket - special system channels in the cylinder block and the block head through which the fluid moves. If we consider everything in a simple way, then it looks like this: there is a block in which the cylinders are installed, as well as the main components and mechanisms. A shell is made on top of this block, and the space between them is used as channels for fluid movement. This design allows the fluid to wash over the cylinders, pass next to the units installed in the block and the head, which ensures heat removal from them.

2. Pump

It looks like water pump

A water pump is installed in the cooling jacket. It consists of a drive gear (pulley) and an impeller, which is placed inside the shirt, fitted on one axis. It is driven from the crankshaft using a belt.

It is the water pump that circulates the fluid through the system. Receiving rotation from the crankshaft, the impeller forces the fluid to move through the channels of the jacket.

3. Radiator

In this case, antifreeze circulates not only in the shirt. If this were the case, then the liquid would have nowhere to give heat, that is. To prevent this from happening, it is included in the design.

It is a structure of two tanks - one is supplied with liquid from the jacket, and from the second it returns back. These tanks are interconnected by a large number of tubes through which the liquid moves between them. So that the radiator is made of metals with high thermal conductivity (copper, aluminum, brass). Also, in order to increase heat transfer between the tubes, special tapes are placed, laid in a certain way and having a large number of points of contact with the tubes.

The liquid passing through the tubes gives off some of the heat to the tapes. The air passing through the radiator removes heat and removes it into environment... To ensure good air flow, the radiator is installed in the front of the car. The radiator with a cooling jacket is connected using rubber pipes.

Separately, we note that thanks to the liquid system, it was possible to provide and. For this, another radiator was included in the cooling system, which was placed in the cabin. Structurally, it is the same as the main radiator, but smaller in size. The air flow for it is created using an electric motor with a fan.

Video: Engine overheating. Consequences of overheating.

4. Thermostat

The cooling system must ensure the fastest possible output of the power plant to the optimal temperature regime. And to ensure this, a thermostat is included in the design. To understand what it is for - a little theory.

If the design of the system consisted only of a jacket and a pump, then the engine would overheat very quickly, since the liquid moved only through the channels in the block and there would be nowhere to remove heat.

The device and principle of operation of the thermostat

To avoid this, a radiator was included in the design. But due to its presence, the volume increased, besides, the purpose of the radiator is to remove heat, so the engine will reach the desired temperature for a very long time, especially in winter.

To ensure a quick access to the required temperature, the cooling system was divided into two rings - small (only the cooling jacket and pump are involved) and large (jacket + pump + radiator).

The thermostat is also engaged in the division into rings. It is a valve that is triggered by an increase in temperature. On different cars its response temperature is different, but in general it works in the range - 85-95 degrees. FROM.

The thermostat housing is usually located on the cylinder block near the channel leading to the radiator. As long as the temperature of the motor is low, the thermostat closes this channel and the liquid moves only along the jacket. As the temperature rises, this valve begins to open gradually, letting the liquid through the large ring, with the involvement of the radiator. When a certain temperature value is reached, it opens completely, and the liquid already moves only along the large ring.

5. Fan, sensors

The principle of operation of the cooling fan

It so happens that the air flow is not enough to ensure normal heat removal from the radiator. For example, this happens in a traffic jam when the engine is constantly running, but there is no oncoming air flow, since the car is immobilized.

To prevent the liquid from overheating, a fan is used to create a forced air flow. It is located behind the main radiator and is driven by an electric motor. Its inclusion in work is carried out due to the temperature sensor installed in the radiator.

Additionally, the design also includes a temperature one, which transmits temperature data to dashboard in the cabin, so the driver can constantly monitor the temperature of the engine and notice the appearance of a malfunction in time, which is why the temperature of the engine "went up".

The main malfunctions of the cooling system

There are not so many malfunctions in the engine cooling system, but the consequences from them can be very serious. The main ones are:

• Leakage of coolant;
• Malfunction of the pump, thermostat;
• Damaged sensor wiring.

Video: All causes of engine overheating and boiling. Elimination of the causes of overheating of the VAZ NIVA engine

Liquid leakage can occur due to breakdown of the cooling jacket, cylinder head gaskets, rubber pipes, radiator or due to unreliable fastening of the connection points.

It is not difficult to identify this malfunction, since as a result of a leak under the car, a puddle of coolant will form. If the leak is not eliminated in a timely manner, then most of the coolant may leak out, and the system will no longer be able to maintain the temperature regime.

Pump failure is often associated. This is accompanied by traces of smudges on the drive side, increased noise during engine operation, and uneven wear of the drive belt.

If the pump is not replaced in a timely manner, then there is a possibility that it will jam and break drive belt, and this is already fraught with quite serious problems, since often the timing belt is also put into operation with this belt.

The problem with a thermostat is usually that it gets stuck in one position. Because of this, the transfer of liquid between the rings is not carried out, it moves either only along a small one, or along a large circle.

Damage to the wiring or sensors leads to the fact that the readings to the dashboard are not transmitted or do not correspond to reality, and the fan does not turn on at the required time or it runs constantly, which is why the temperature regime is violated.

The modern car enthusiast is more and more interested in the device of the car. In studying car device, it is difficult to ignore such an important part as maintaining the temperature regime in the car engine. CO (Engine Cooling System), the most important component of any machine. The wear and productivity of the engine of the machine depend on the correctness of its functioning. Serviceable CO, significantly reduces the load on the working elements of the engine. To maintain the correct functioning of the system, it is necessary to have a good understanding of its components. After reviewing the helpful materials, you will be able to serve COs competently.

During the operation of the car, the working parts of the engine are able to gain high temperatures. To avoid overheating of the working parts, the car is equipped with a cooling system. The cooling system of the car significantly reduces the temperature of the working parts of the engine. Maintaining optimal temperature conditions is due to working fluid... The working mixture circulates through special conductors, preventing overheating. The system, on all vehicles, performs a number of additional functions.

Cooling system functions.

• Optimization of the mixture temperature for lubricating the working parts of the car.
• Exhaust gas temperature regulation in the exhaust system.
• Lowering the temperature of the mixture for the automatic transmission.
• Lowering the air temperature in the car's turbine.
• Heating the air flow in the heating system.

Today, there are several types of cooling systems. Systems are separated in particular from the method of lowering the temperature of the working parts.

Types of cooling systems.

• Closed. In this system, the temperature decrease is due to the working fluid.
• Open (Air). In an open system, the temperature is reduced by air flow.
• Combined. The cooling system under consideration combines two types of cooling. Particularly from the system manufacturer, the cooling is done jointly or sequentially.

The most popular in mechanical engineering is the engine cooling system using coolant. The cooling system under consideration has become the most effective and practical for operation. The cooling system evenly lowers the temperature of the working parts of the engine. Let's consider the device and the way of the system functioning, using the most popular example.

Regardless of the features of the engine, the design and functioning of the cooling system does not differ much. Thus, engines with different kind fuels have an almost identical temperature control system. The cooling system includes components that ensure its functioning. Each component is extremely important for full-fledged work. In case of malfunction of one component, the correct optimization of the temperature regime is violated.

Components of cooling systems.

• Coolant heat exchanger.
• Oil heat exchanger.
• Fan.
• Pumps. In particular, from the OS model, there may be several of them.
• Working mixture tank.
• Sensors.

For the functioning of the working mixture, there are special conductors in the system. The control of the system operation is carried out thanks to the central control system.

The heat exchanger lowers the temperature of the liquid by a flow of cold air. To change the heat output, the heat exchanger is equipped with a certain mechanism, which is a small tube.

Along with the standard transmitter, some manufacturers equip the system with a heat exchanger for oil and recycled gases. The oil heat exchanger reduces the temperature of the fluid that lubricates the working components. The second is necessary to lower the temperature of the exhaust mixture. Exhaust Circulation Regulator - Reduces the production temperature of the fuel and air combination. This reduces the amount of nitrogen produced during engine operation. For the correct operation of the device in question, a special compressor is responsible. The compressor sets the working mixture in motion, moving it through the system. The device is built into the OS.

The heat exchanger is responsible for the opposite action. The device increases the temperature of the air flow operating through the system. To ensure maximum productivity, the mechanism is located on the coolant outlet from the vehicle engine.

The expansion barrel is designed to fill the system with a working mixture. Thanks to this, fresh coolant enters the conductors, restoring the volume of the used one. Thus, the level of the mixture always remains necessary.

The movement of the coolant takes place thanks to the central pump. Depending on the manufacturer, the pump is driven in different ways. Most pumps are driven by a belt or gear. Some manufacturers equip the OS with another pump. Additional pump, required when equipping the mechanism with a compressor to cool the air flow. The engine control unit is responsible for the functioning of all pumps in the system.

For creating optimal temperature liquid, a thermostat is provided. This device identifies the volume of liquid (moving through the radiator) that needs to be cooled. Thus, the necessary temperature regime is created for the correct operation of the engine. The device is located between the radiator and the mixture conductor.

Large displacement motors are equipped with electric thermostats. This view devices, change the temperature of the liquid in several stages. The device has several modes of operation: free, closed and intermediate. When, the load on the engine becomes extreme, thanks to electric drive, the thermostat is set to free operation. In this case, the temperature drops to required level... In particular, from the pressure on the engine, the thermostat operates in the mode of maintaining the optimum temperature.

The fan is responsible for improving the efficiency of regulating the temperature of the liquid. The fan drive differs depending on the OS model and manufacturer.

Fan drive types:

• Mechanics. This type of drive establishes continuous contact with the hardened shaft of the engine.
• Electrician. In this case, the fan is driven by an electric motor.
• Hydraulics. Special coupling with hydraulic drive, directly activates the fan.

Due to the possibility of adjustment and a variety of operating modes, the most popular is the electric drive.

Sensors are important components of the set. The coolant level and temperature sensor allows you to monitor the required parameters and restore them in a timely manner. Also, the device contains a central control unit and adjustment elements.

The coolant temperature sensor determines the indicator of the working fluid and converts it into digital format for transmission to the device. At the radiator outlet, a separate sensor is installed to expand the functionality of the cooling system.

The electrical unit receives readings from the sensor and transmits it special devices... The block also changes the indicators for the impact, determining the required direction. For this, there is a special software installation in the block.

To carry out actions and adjust the temperature of the coolant, the mechanism is equipped with a number of special devices.

OS executive systems.

• Thermostat temperature regulator.
• Main and secondary compressor switch.
• Fan mode control unit.
• The block that regulates the operation of the OS after the engine stops.

The principles of the cooling system.

The control over the operation of the cooling system is carried out by the central engine control unit. Most cars are equipped with a system based on a certain algorithm. The necessary working conditions and the period of certain processes are determined using the corresponding indicators. Optimization is based on the sensor readings (coolant temperature and level, lubricant temperature). Thus, optimal processes are set for maintaining the temperature regime in the car engine.

The central pump is responsible for the constant movement of the coolant along the conductors. Under pressure, the liquid moves continuously along the conductors of the OC. Thanks to this process, the temperature of the working parts of the engine decreases. Depending on the characteristics of a particular mechanism, several directions of movement of the mixture are distinguished. In the first case, the mixture is directed from the initial cylinder to the final one. In the second, from the outlet collector to the inlet.

Based on the temperature readings, the liquid flows in a narrow or wide arc. When starting the engine, working elements and fluid, including, have a low temperature. For a quick rise in temperature, the mixture moves in a narrow arc without cooling the radiator. During this process, the thermostat is in closed mode. Thus, operational warming up of the engine is achieved.

As the temperature of the engine elements rises, the thermostat goes into free mode (opening the cover). In this case, the liquid begins to pass through the radiator, moving in a wide arc. The air flow in the radiator cools the heated liquid. A fan can also be an auxiliary element for cooling.

After creating the required temperature, the mixture passes into the conductors located on the engine. While the vehicle is running, the temperature optimization process is constantly repeated.

On vehicles equipped with a turbine, a special cooling mechanism with two levels is installed. In this, there is a separation of the coolant conductors. One of the levels is responsible for cooling the car engine. The second one cools the air flow.

The cooling device is especially important for correct work car. If a malfunction occurs in it, the engine may overheat and fail. Like any component of a car, the OS requires timely maintenance and care. One of the most important elements for maintaining the temperature regime is the coolant. This mixture must be changed regularly, according to the manufacturer's recommendations. In case of malfunctions in the OS, it is not recommended to operate the car. This can expose the engine to high temperatures. To avoid serious malfunctions, it is necessary to quickly diagnose the device. Having studied the device and the principle of operation, you can determine the nature of the malfunction. If serious malfunctions occur, consult a professional. This knowledge will also be useful to you in this. Service the device in a timely manner and you will significantly increase its service life. Good luck with the useful material.

The first production car was produced by Ford at the beginning of the 20th century. He wore the proud "T" prefix and represented another milestone in human development. Prior to that, cars were the lot of a handful of enthusiasts who ran hauls and occasionally drove to the afternoon promenade.

Henry Ford made a real revolution. He put cars on the assembly line, and soon his cars filled all the roads of America. Moreover, factories were opened in the Soviet Union as well.

Henry Ford's main paradigm was very simple: "A car can have any color as long as it is black." This approach made it possible for each person to have their own car. Optimizing costs and scaling up production have made the price truly affordable.

Much time has passed since then. Cars evolved incessantly. Most of the changes and additions were made to the engine. The cooling system played a special role in this process. It has been improved year after year, allowing the engine to extend its life and avoid overheating.

Engine cooling system history

It should be admitted that the engine cooling system has always been in cars, however, its design has changed dramatically over the years. If you look exclusively at the present day, then in most cars the liquid type is installed. Its main advantages include compactness and high performance.But this was not always the case.

The first engine cooling systems were extremely unreliable. Perhaps, if you strain your memory, then remember the films in which events take place in the late 19th and early 20th centuries. Back then, a car on the side of the road with a smoking engine was common.

Attention! Initially, the main reason for engine overheating was the use of water as a coolant.

As a motorist, you should know that modern cars antifreeze is used as a resource for the cooling system. Its counterpart was even in the Soviet Union, it was only called antifreeze.

Basically, they are one and the same substance. It is based on alcohol, but due to additional additives, the effectiveness of antifreeze is dramatically higher. For example, antifreeze in the engine cooling system covers protective film absolutely everything that has an extremely negative effect on heat transfer. Because of this, the resource of the motor is reduced.

Antifreeze works in a completely different way.It only covers with a protective film problem areas... Also, among the differences, you can recall the additional additives that are in antifreeze, different boiling temperatures, and so on. In any case, comparison with water will be most revealing.

Water boils at a temperature of 100 degrees. The boiling point of antifreeze is about 110-115 degrees.Naturally, thanks to this, cases of engine boiling have practically disappeared.

It is worth recognizing that the designers have carried out many experiments aimed at upgrading the engine cooling system. It is enough to remember exclusively air cooling... Such systems were quite actively used in the 50-70s of the last century. But due to low efficiency and cumbersomeness, they quickly fell out of use.

Successful examples of vehicles with air-cooled engine cooling systems include:

• Fiat 500,
• Citroën 2CV,
• Volkswagen Beetle.

There were also cars in the Soviet Union that were powered by an air-cooled engine. Perhaps every motorist born in the USSR remembers the legendary "Cossacks", whose engine was installed in the back.

How a liquid engine cooling system works

The layout of the liquid cooling system is not overly complicated. Moreover, all designs, regardless of which companies were engaged in their production, are similar to each other.

Device

Before proceeding to consider the principle of operation of the engine cooling system, it is necessary to study the main structural elements. This will allow you to imagine exactly how everything happens inside the device. Here are the main details of the node:

• Cooling jacket. These are small cavities filled with antifreeze. They are located where cooling is most needed.
• The radiator dissipates heat into the atmosphere. Usually its cells are made from a combination of alloys to achieve the highest efficiency. The structure must not only effectively reduce the temperature of the liquid, but also be durable. After all, even a small pebble can cause a hole. The system itself consists of a combination of tubes and edges.
• The fan is mounted on the back of the radiator so as not to interfere with the oncoming air flow. It works with an electromagnetic or hydraulic clutch.
• The thermal sensor records the current state of the antifreeze in the engine cooling system and, if necessary, starts it up in a large circle. This device is installed between the pipe and the cooling jacket. In fact, this structural element is a valve, which can be either bimetallic or electronic.
• The pump is a centrifugal pump. Its main task is to provide continuous circulation of matter in the system. The device works with a belt or gear. Some motor models may have two pumps at once.
• Radiator heating system... In terms of size, it is slightly inferior to a similar device for the entire cooling system. In addition, it is located inside the cabin. Its main task is to transfer heat to the car.

Of course, these are not all elements of the engine cooling system, there are also pipes, pipes and many small parts. But for a general understanding of the operation of the entire system, such a list is quite enough.

Principle of operation

IN engine cooling system there is an inner and outer circle. According to the first, the coolant circulates until the temperature of the antifreeze reaches a certain point. This is usually 80 or 90 degrees. Each manufacturer sets its own limits.

As soon as the threshold temperature is exceeded, the liquid begins to circulate in the second circle. In this case, it passes through special bimetallic cells, in which it is cooled. Simply put, the antifreeze enters the radiator, where it quickly cools down with the help of the oncoming air flow.

This engine cooling system is quite effective, as it allows the car to work even at top speeds. In addition, the counter air flow plays an important role in cooling.

Attention! The engine cooling system is responsible for the operation of the stove.

To better explain how it works modern systems engine cooling let's go a little deeper into design features scheme. As you know, the main element of an engine is the cylinders. During the trip, pistons constantly move in them.

If we take as an example gas engine, then during contraction the candle starts a spark. It ignites the mixture, resulting in a small explosion. Naturally, the temperature at this time reaches several thousand degrees.

So that there is no overheating and there is a liquid jacket around the cylinders. She takes some of the heat and then gives it back. Antifreeze is constantly circulating in the engine cooling system.

How the use of different coolants affects the cooling system

As mentioned above, previously, ordinary water was used in cooling systems. But this decision could not be called extremely successful. Besides the fact that the engines were constantly boiling, there was another side effect, namely, scale. In large numbers, she paralyzed the operation of the device.

Scale is caused by the chemical structure of the water. The fact is that in practice water cannot be 100% pure. The only way to achieve complete elimination of all foreign elements is distillation.

Antifreeze, circulating inside the engine cooling system, does not create scale. Unfortunately, the process of constant operation does not pass without leaving a trace for them. Substances decompose under the influence of high temperatures. The result of this process is the formation of decay products in the form of a coating of corrosion and organic matter.

Quite often, foreign substances get into the coolant circulating inside the system. As a result, the efficiency of the entire system is significantly degraded.

Attention! The greatest harm is caused by the sealant. Particles of this substance, when sealing holes, get inside, mixing with the coolant.

The result of all these processes is that a variety of deposits are formed inside the engine cooling system. They impair thermal conductivity. In the worst case, blockages form in the pipes. This, in turn, leads to overheating.

Frequent system malfunctions

Certainly fluid systems refrigerators have many advantages in comparison with their closest counterparts. But even they sometimes fail. Most often, a leak forms in the structure, which leads to fluid leakage and deterioration of engine performance.

A leak in the engine cooling system can occur for the following reasons:

1. Due to severe frosts the liquid inside froze and the structure was damaged.
2. A common reason the formation of a leak is the leakage of the connection of the hoses with the nozzles.
3. High carbonization can also cause leakage.
4. Loss of elasticity due to high temperatures.
5. Mechanical damage.

It is the latter reason, according to statistics, that most often causes leaks in engine cooling systems. Most of the blows are in the area of \u200b\u200bthe radiator. The stove also suffers quite often.

Also, in the engine cooling system, the thermostat often fails. This is due to constant contact with the coolant. The result is a corrosive layer.

Outcome

The design of the engine cooling system may not seem particularly complicated. But it took years of experiments and thousands of unsuccessful attempts... But now every car can work to its limit thanks to high-quality heat removal from the engine.

Cooling system

The cooling system is designedto maintain normal thermal conditions of the 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 remove heat from the engine, then in a few tens of seconds after starting it will no longer be cold, but hopelessly hot. Next time you can start your cold engine only after it overhaul.

The cooling system is necessary to remove heat from the mechanisms and engine parts, but this is only half of its purpose, however, more than half.

It is also important to speed up the warm-up of a cold engine to ensure normal operation. And this is the second part of the cooling system.

As a rule, cars use a closed-type liquid cooling system with forced circulation of liquid and an expansion tank (Fig. 29).

The cooling system consists of:

cooling jacket of the block and cylinder head,

centrifugal pump,

thermostat,

radiator with expansion tank,

fan,

connecting pipes and hoses.

In fig. 29 you can easily distinguish between the two circles of coolant circulation.

Figure: 29. Engine cooling system diagram:1 - radiator; 2 - branch pipe for circulation of coolant; 3 - expansion tank; 4 - thermostat; 5 - water pump; 6 - cooling jacket of the cylinder block; 7 - cooling jacket of the block head; 8 - heater radiator with electric fan; 9 - heater radiator tap; ten – a plug for draining the coolant from the block; 11 - plug for draining the coolant from the radiator; 12 - fan

A small circle of circulation (red arrows) serves to warm up a cold engine as soon as possible. And when the blue ones join the red arrows, the already heated liquid begins to circulate in a large circle, cooling in the radiator. Leads this process automatic device – thermostat.

To monitor the operation of the cooling system, there is a coolant temperature gauge on the instrument panel (see Fig. 67). The normal temperature of the coolant when the engine is running should be within 80–90 ° C.

Engine cooling jacketconsists of many channels in the block and the cylinder head through which coolant circulates.

Centrifugal pumpforces fluid to move through the engine cooling jacket and the entire system. The pump is driven by a belt drive from the engine crankshaft pulley. The belt tension is adjusted by the deflection of the generator housing (see Fig. 63 a) or tension roller drive camshaft engine (see Fig. 11 b).

Thermostatdesigned to maintain a constant optimal thermal condition of the engine. When starting a cold engine, the thermostat is closed, and all the liquid circulates only in a small circle (Fig. 29 a) for its quickest warming up. When the temperature in the cooling system rises above 80–85 ° С, the thermostat automatically opens and part of the liquid enters the radiator for cooling. At high temperatures, the thermostat opens completely, and now all the hot liquid is directed along a large circle for its active cooling.

Radiatorserves to cool the fluid passing through it due to the air flow that is created when the car is moving or with the help of a fan. The radiator contains many tubes and baffles that provide a large cooling surface area.

Expansion tankit is necessary to compensate for changes in the volume and pressure of the coolant when it is heated and cooled.

Fanis designed to forcibly increase the air flow passing through the radiator of a moving car, as well as to create an air flow when the car is stationary with the engine running.

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

Connections and hosesserve to connect the cooling jacket to the thermostat, pump, radiator and expansion tank.

The engine cooling system also includes interior heater.Hot coolant flows through heater radiatorand heats the air supplied to the vehicle interior.

The air temperature in the passenger compartment is regulated by a special crane,by which the driver increases or decreases the flow of fluid passing through the heater radiator.

The main malfunctions of the cooling system

Leakage of coolantmay result from damage to the radiator, hoses, gaskets and oil seals.

To eliminate the malfunction, it is necessary to tighten the hose and pipe clamps, and replace the damaged parts with new ones. If the radiator pipes are damaged, you can try to patch holes and cracks, but, as a rule, everything ends up replacing the radiator.

Engine overheatingoccurs due to insufficient coolant level, weak fan belt tension, clogged radiator pipes, as well as a thermostat malfunction.

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

Often, engine overheating also occurs with serviceable elements of the cooling system, when the machine is moving at low speed and high engine loads. This happens when driving in heavy road conditionssuch as country roads and 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 "respites".

Be careful while driving and do not allow emergency mode engine running! Remember that even a single overheating of the engine violates the metal structure, while the lifespan of the "heart" of the car is significantly reduced.

Cooling system operation

When operating the vehicle, you should periodically look under the hood. A timely noticed malfunction in the cooling system will allow you to avoid overhaul of the engine.

If a coolant level in the expansion tankhas dropped or the liquid is absent altogether, then first you need to top it up, and then you should figure out (on your own or with the help of a specialist) where it went.

During the operation of the engine, the liquid is heated to a temperature close to the boiling point. This means that the water in the coolant will gradually evaporate.

If after six months of daily operation of the car, the level in the tank has dropped slightly, then this is normal. But if yesterday there was a full tank, and today it is only on the bottom, then you need to look for the place of the coolant leak.

Fluid leakage from the system can be easily identified by dark spots on the asphalt or snow after more or less prolonged parking. Opening the hood, you can easily find the leak by comparing the wet marks on the asphalt with the location of the cooling system elements under the hood.

The fluid level in the reservoir must be checked at least once a week. If the level has dropped significantly, 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 become seriously "ill" and require "hospitalization".

Almost all domestic cars as a coolant, a special low-freezing liquid with the name Tosol A-40.Numeral 40 shows the negative temperature at which the liquid begins to freeze (crystallize). In the conditions of the Far North, Antifreeze A-65 , and, accordingly, it begins to freeze at a temperature of minus 65 ° C.

Antifreeze is a mixture of water with ethylene glycol and additives. This solution combines a lot of advantages. Firstly, it begins to freeze only after the driver himself has frozen (joke), and secondly, Tosol has anti-corrosion, anti-foaming properties and practically does not form deposits in the form of ordinary scale, since it contains pure distilled water ... therefore only distilled water can be added to the cooling system.

When operating a car, you must control not only the tension, but also the condition of the water pump drive belt,as its break on the road is always unpleasant. It is recommended to have a spare belt in the travel kit. If not yourself, then some kind people will help you change it.

Coolant can boil and cause engine damage if it fails fan electric drive sensor.If the electric fan has not received the command to turn on, then the liquid continues to heat up, approaching the boiling point, without cooling aid.

But the driver has a device with an arrow and a red sector in front of his eyes! Moreover, there is almost always a slight additional noise when the fan is turned on. There would be a desire to control, but there will always be ways.

If on the way (and more often in a "traffic jam") you notice that the coolant temperature is approaching a critical one, and the fan is running, then in this case there is a way out. It is necessary to include an additional radiator in the operation of the cooling system - a radiator for the interior heater. Fully open the heater tap, turn on the heater fan at all revolutions, lower the door windows and sweat to the house or to the nearest car service. But at the same time, continue to closely follow the arrow of the engine temperature gauge. If it does enter the red zone, stop immediately, open the hood and "cool down".

May cause trouble over time thermostat,if he stops letting fluid through a large circle of circulation. Determining if a thermostat is working is not difficult. The radiator should not heat up (determined by hand) until the arrow of the coolant temperature gauge reaches the middle position (thermostat closed). Later, the hot liquid will begin to flow into the radiator, quickly heating it, which indicates the timely opening of the thermostat valve. If the radiator continues to be cold, then there are two ways. Knock on the thermostat body, maybe it will open after all, or immediately, morally and financially, prepare for its replacement.

Immediately "surrender" to the mechanic if oil dipstick you will see droplets of fluid from the cooling system into the lubrication system. It means that damaged cylinder head gasketand coolant seeps into the oil pan. If you continue to operate the engine with oil half consisting of Tosol, then the wear of engine parts becomes catastrophic.

Water pump bearingdoes not break "suddenly". First, there will be a specific whistling sound from under the hood, and if the driver “thinks about the future”, he will promptly replace the bearing. Otherwise, it will still have to be changed, but with the consequence of being late to the airport or to a business meeting, because of a "suddenly" broken down car.

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

If the engine of your car is overheated and "boiled", then, of course, you need to stop and open the hood of the car, but you cannot open the radiator cap or expansion tank... To speed up the engine cooling process, this will practically do nothing, and you can get severe burns.

Everyone knows what an awkwardly opened bottle of champagne turns into for smartly dressed guests. In a car, everything is much more serious. If you quickly and thoughtlessly open the plug of a hot radiator, then a fountain will fly out, but not wine, but boiling Tosol! In this case, not only the driver may be injured, but also pedestrians who are nearby. Therefore, if you ever have to open the cap of a radiator or expansion tank, then you should first take precautions and do it slowly.

Any car uses an internal combustion engine. Liquid cooling systems are widespread - only the old Zaporozhets and the new Tata use air blowing. It should be noted that the circulation pattern on all machines is practically similar - the same elements are present in the design, they perform identical functions.

Small cooling circle

There are two circuits in the cooling system of an internal combustion engine - small and large. It is somewhat similar to human anatomy - the movement of blood in the body. The liquid moves in a small circle when it is necessary to produce quick warm-up to operating temperature. The problem is that the motor can function normally in a narrow temperature range - about 90 degrees.

It is impossible to increase or decrease it, as this will lead to violations - the ignition timing will change, fuel mixture will burn out out of time. A radiator for the interior heater is included in the circuit - after all, it is necessary that the inside of the car was warm as early as possible. The hot antifreeze supply is shut off with a tap. The place of its installation depends on the specific car - on the partition between the passenger compartment and engine compartment, in the area of \u200b\u200bthe glove compartment, etc.

Large cooling circuit

In this case, the main radiator is also included. It is installed in the front of the car and is designed to urgently reduce the temperature of the fluid in the engine. If the car has an air conditioner, then the radiator is installed next to it. On Volga and Gazelle cars, an oil cooler is used, which is also installed in the front of the car. The radiator usually has a fan that is driven by an electric motor, belt or clutch.

Liquid pump in the system

This device is included in the coolant circulation circuit of the Gazelle and any other vehicle. The drive can be carried out as follows:

1. From the timing belt.
2. From the alternator belt.
3. From a separate strap.

The design consists of the following elements:

1. Metal or plastic impeller. The efficiency of the pump depends on the number of blades.
2. Body - usually made of aluminum and its alloys. The fact is that this particular metal works well in aggressive conditions; corrosion practically does not affect it.
3. The pulley for installing the drive belt is toothed or wedge-shaped.
4. The shaft is a steel rotor, at one end of which there is an impeller (inside), and on the outside there is a pulley for installing a drive pulley.
5. Bronze bushing or bearing - these elements are lubricated using special additives that are present in antifreeze.
6. The oil seal avoids fluid leakage from the cooling system.

Thermostat and its features

It is difficult to say which element provides the most efficient liquid circulation in the cooling system. On the one hand, the pump creates pressure and antifreeze moves through the pipes with its help.

But on the other hand, if there was no thermostat, the movement would occur exclusively in a small circle. The design contains the following elements:

1. Aluminum body.
2. Outlets for connection with branch pipes.
3. The plate is bimetallic.
4. Spring return mechanical valve.

The principle of operation is that at temperatures below 85 degrees, the liquid moves only along a small circuit. In this case, the valve inside the thermostat is in such a position that antifreeze does not enter the large circuit.

As soon as the temperature reaches 85 degrees, it will begin to deform. It acts on the mechanical valve and opens access to the antifreeze to the main radiator. As soon as the temperature drops, the thermostat valve will return to its original position by the return spring.

Expansion tank

The cooling system of the internal combustion engine has an expansion tank. The fact is that any liquid, including antifreeze, increases its volume when heated. And when it cools, the volume decreases. Therefore, some kind of buffer is needed in which a small amount of liquid will be stored so that the system always has enough of it. It is with this task that the expansion tank copes - the surplus spills out there during heating.

Expansion tank cap

Another irreplaceable component of the system is the cork. There are two types of construction - sealed and non-sealed. In the event that the latter is used on the car, the expansion tank plug has only a drain hole through which the pressure in the system is balanced.

But if a sealed system is used, then there are two valves in the plug - an intake valve (it takes air from the atmosphere inside, operates at a pressure below 0.2 bar) and an exhaust valve (operates at a pressure above 1.2 bar). It throws excess air out of the system.

It turns out that the pressure in the system is always greater than in the atmosphere. This allows you to slightly increase the boiling point of the antifreeze, which has a beneficial effect on engine operation. This is especially good for traffic jams in urban environments. An example of a sealed system is VAZ-2108 cars and similar. Leaky - models of the classic VAZ series.

Radiator and fan

The coolant circulates through the main radiator, which is installed at the front of the vehicle. This place was not chosen by chance - when driving with high speed the radiator honeycomb is blown by the oncoming air flow, which reduces the engine temperature. A fan is installed on the radiator. Most of such devices have On Gazelles, for example, couplings similar to those installed on air conditioner compressors are often used.

Inclusion electric fan occurs using a sensor installed at the bottom of the radiator. The signal from the temperature sensor, which is located on the thermostat housing or in the engine block, can be used on injection machines. The most simple circuit inclusion contains only one thermal switch - its contacts are normally open. As soon as the temperature reaches 92 degrees at the bottom of the radiator, the contacts inside the switch will close and voltage will be supplied to the fan motor.

Interior heater

This is the most important part when viewed from the perspective of the driver and passengers. The efficiency of the stove depends on the comfort when driving in winter time of the year. The heater is included in the coolant circulation circuit and consists of the following components:

1. Electric motor with impeller. It turns on according to a special scheme, in which there is a constant resistor - it allows you to change the speed of the impeller.
2. A radiator is an element through which hot antifreeze flows.
3. Tap - designed to open and close the supply of antifreeze to the inside of the radiator.
4. The duct system allows hot air to be directed in the desired direction.

The scheme of circulation of the coolant through the system is such that when just one entrance to the radiator is closed, hot antifreeze will not get into it in any way. There are cars in which there is no stove tap - there is always hot antifreeze inside the radiator. And in summer time the air ducts are simply closed and heat is not supplied to the passenger compartment.