Engine cooling VAZ 2104, 2105, 2107
Engine cooling VAZ 2104, 2105, 2107: 1. Fluid drain pipe from the heater radiator to the coolant pump; 2. Coolant drain hose from the inlet pipe; 3. Coolant drain hose from the heater radiator; 4. Liquid supply hose to the heater radiator; 5. Thermostat bypass hose; 6. Cooling jacket outlet pipe; 7. Radiator inlet hose; 8. Expansion tank; 9. Tank cap; 10. Hose from the radiator to the expansion tank; 11. Radiator cap; 12. Plug outlet valve; 13. Inlet valve; 14. Upper radiator tank; 15. Radiator filler neck; 16. Radiator pipe; 17. Radiator cooling fins; 18. Fan casing; 19. Electric fan; 20. Coolant pump drive pulley; 21. Rubber support; 22. Window on the side of the cylinder block for supplying coolant; 23. Oil seal cage; 24. Coolant pump roller bearing; 25. Pump cover; 26. Pump drive pulley hub; 27. Pump roller; 28. Locking screw; 29. Oil seal cuff; 30. Pump housing; 31. Pump impeller; 32. Pump inlet pipe; 33. Lower radiator tank; 34. Radiator outlet hose; 35. Coolant pump drive belt; 36. Coolant pump; 37. Coolant supply hose to the pump; 38. Thermostat; 39. Rubber insert; 40. Inlet pipe (from the radiator); 41. Main valve; 42. Bypass valve; 43. Thermostat housing; 44. Overflow hose connection; 45. Hose connection for supplying coolant to the pump; 46. Thermostat cover; 47. Piston of the working element; 48. I. Thermostat operation diagram; 49. II. Liquid temperature less than 80 C; 50.III. Liquid temperature 80 - 94 C; 51.IV. Liquid temperature is more than 94 C. The engine cooling system is liquid, closed type, with forced circulation of liquid. System capacity is 9.85 liters, including the interior heating system. The cooling system consists of the following elements: coolant pump 36, radiator, expansion tank 8, pipelines and hoses, electric fan 19, block cooling jackets and cylinder head.
When the engine is running, liquid heated in the cooling jackets flows through the outlet pipe 6 through hoses 5 and 7 into the radiator or thermostat, depending on the position of the thermostat valves. Next, the coolant is sucked in by pump 36 and supplied again to the cooling jackets. The engine cooling system is liquid, closed type, with forced circulation of liquid. System capacity is 9.85 liters, including the interior heating system. The cooling system consists of the following elements: coolant pump 36, radiator, expansion tank 8, pipelines and hoses, fan 19, block cooling jackets and cylinder head.
When the engine is running, liquid heated in the cooling jackets flows through the outlet pipe 6 through hoses 5 and 7 into the radiator or thermostat, depending on the position of the thermostat valves. Next, the coolant is sucked in by pump 36 and supplied again to the cooling jackets. Checking the coolant level is carried out on a cold engine (at a temperature of plus 15-20 C) by checking the liquid level in the expansion tank 8, which should be 3-4 mm above the “MIN” mark. To monitor the coolant temperature, there is a sensor installed in the cylinder head and a pointer on the instrument panel.
Under normal temperature conditions of engine operation, the indicator arrow stands at the beginning of the red field of the scale within 80-100 C. The transition of the arrow to the red zone indicates an increased thermal condition of the engine, which can be caused by problems in the cooling system (loose pump drive belt, insufficient amount of coolant fluid, malfunctioning thermostat or electric fan), as well as difficult road conditions.
The fluid is drained from the system through drain holes closed by plugs: one in the left corner of the lower radiator tank 33, the other in the cylinder block on the left in the direction of travel of the car. The car's interior heater is connected to the cooling system. The heated liquid from the cylinder head flows through hose 4 through the tap into the heater radiator, and is sucked off through hose 3 and tube 1 by pump 36.
The coolant pump is a centrifugal type, driven from the crankshaft pulley by a generator drive V-belt. The pump is attached to the cylinder block on the right side through a gasket. The pump housing 30 and cover 25 are cast from aluminum alloy. A roller 27 is installed in the bearing cover 24, which is locked with a screw 28. Bearing 24 is double-row, non-separable, without an inner race. The bearing is filled with grease during assembly and is not subsequently lubricated. The impeller 31 is pressed onto the roller 27 on one side, and the hub 26 of the pump drive pulley on the other.
The end of the impeller in contact with the sealing ring is hardened with high frequency currents to a depth of 3 mm. The sealing ring is pressed against the impeller by a spring through a rubber cuff 29. The seal is non-separable and consists of an outer brass ring 23, a rubber cuff and a spring. It is pressed into the pump cover 25. The pump housing has an inlet pipe 32 and a window 22 towards the cylinder block for supplying coolant to the pump. With normal tension of the pump drive belt, its deflection under a force of 10 kgf should be within 10-15 mm.
Electric fan. The fan is four-blade, made of plastic. The fan blades have a variable radius installation angle and, to reduce noise, a variable pitch along the hub. The fan is installed on the motor shaft and pressed with a nut. For better operating efficiency, the fan is located in a casing 18, which is bolted to the radiator brackets. The electric motor and fan assembly is mounted on three rubber bushings and secured with nuts to the studs of the fan casing 18. The electric fan 19 is turned on and off automatically depending on the fluid temperature using a TM-108 type sensor installed in the lower radiator tank on the left side. The sensor contact closing temperature should be within 89-95 C, and opening temperature within 84-90 C.
Radiator. A radiator with upper and lower tanks, with two rows of brass vertical tubes and tinned cooling plates is attached with four bolts to the front of the body and rests on rubber supports 21. The filler neck 15 of the radiator is closed with plug I and connected by a hose 10 to a translucent plastic expansion tank 8. Radiator plug has an inlet valve 13 and an outlet valve 12, through which the radiator is connected by a hose to the expansion tank.
The intake valve is not pressed against the gasket (gap 0.5-1.1 mm) and allows coolant to enter and exit into the expansion tank when the engine is heating and cooling. Since 1988, radiators with an aluminum core and plastic tanks have been installed on cars. Thermostat and cooling system operation. The cooling system thermostat accelerates engine warm-up and maintains the required thermal operating conditions of the engine. At optimal thermal conditions, the coolant temperature should be 85 - 95 C. Thermostat 38 consists of a body 43 and a cover 46, which are rolled together with the main valve seat 41.
The thermostat has an inlet pipe 40 for inlet of cooled liquid from the radiator, a pipe 44 of a bypass hose 5 for transferring liquid from the cylinder head to the thermostat, and a pipe 45 for supplying coolant to the pump 36. The main valve is installed in the thermoelement cup, in which a rubber insert 39 is rolled. The rubber insert contains a polished steel piston 47, mounted on a fixed holder. A heat-sensitive solid filler is placed between the walls and the rubber insert. The main valve 41 is pressed against the seat by a spring. Two posts are attached to the valve, on which a bypass valve 42 is installed, pressed by a spring.
The operation of the internal combustion engine of any car is associated with high temperatures. The internal combustion engine heats up during the combustion of the fuel-air mixture in the cylinders and as a result of friction of its elements. The cooling system helps to avoid overheating of the power unit.
General characteristics of the VAZ 2107 cooling system
The VAZ 2107 engine of all models has a sealed liquid cooling system with forced circulation of coolant (coolant).
Purpose of the cooling system
The cooling system is designed to maintain the optimal temperature of the power unit during its operation and timely, controlled removal of excess heat from heating components. Individual elements of the system are used to heat the interior during the cold season.
Cooling system parameters
The cooling system of the VAZ 2107 has a number of parameters that affect the operation and performance of the power unit, the main of which are:
- amount of coolant - regardless of the fuel supply method (carburetor or injection) and engine size, all VAZ 2107 use the same cooling system. According to the manufacturer's requirements, its operation (including interior heating) requires 9.85 liters of refrigerant. Therefore, when replacing antifreeze, you should immediately purchase a ten-liter container;
- engine operating temperature - The operating temperature of the engine depends on its type and volume, the type of fuel used, the number of crankshaft revolutions, etc. For the VAZ 2107 it is usually 80–95 0 C. The engine is heated to operating condition depending on the ambient temperature for 4–7 minutes. If there is a deviation from these values, it is recommended to immediately diagnose the cooling system;
- coolant operating pressure - Since the cooling system of the VAZ 2107 is sealed, and antifreeze expands when heated, a pressure exceeding atmospheric pressure is created inside the system. This is necessary to increase the boiling point of the coolant. So, if under normal conditions water boils at 100 0 C, then when the pressure increases to 2 atm, the boiling point rises to 120 0 C. In the VAZ 2107 engine, the working pressure is 1.2–1.5 atm. Thus, if the boiling point of modern coolants at atmospheric pressure is 120–130 0 C, then under operating conditions it will increase to 140–145 0 C.
The design of the VAZ 2107 cooling system
The main components of the VAZ 2107 cooling system include:
- water pump (pump);
- main radiator;
- main radiator fan;
- interior heater (stove) radiator;
- stove tap;
- thermostat (thermostat);
- expansion tank;
- coolant temperature sensor;
- coolant temperature sensor indicator;
- control temperature sensor (only in injection engines);
- fan switch sensor (only in carburetor engines);
- connecting pipes.
This should also include the engine cooling jacket - a system of special channels in the cylinder block and cylinder head through which coolant circulates.
Video: design and operation of the engine cooling system
Water pump (pump)
The pump is designed to ensure continuous forced circulation of coolant through the engine cooling jacket during operation. It is a conventional centrifugal pump that pumps antifreeze into the cooling system using an impeller. The pump is located on the front of the cylinder block and is driven by the crankshaft pulley through a V-belt.
Pump design
The pump consists of:
Pump operating principle
The operating principle of a water pump is quite simple. When the crankshaft rotates, the belt drives the pump pulley, transmitting torque to the impeller. The latter, rotating, creates a certain coolant pressure inside the housing, forcing it to circulate inside the system. The bearing is designed to rotate the shaft evenly and reduce friction, and the oil seal ensures the tightness of the device.
Pump malfunctions
The pump life for the VAZ 2107 regulated by the manufacturer is 50–60 thousand km. However, this resource may decrease in the following situations:
- use of low-quality coolant or water;
- entry of dirt, impurities, and foreign objects into the cooling system;
- excessive tension on the drive belt.
The result of the influence of these factors are:
- impeller wear;
- wear or damage to the oil seal;
- misalignment of the pump shaft with subsequent wear of the bearing and possible jamming of the device.
When such malfunctions are detected.
Main radiator
The radiator is designed to cool the coolant entering it due to heat exchange with the environment. This is achieved thanks to the features of its design. The radiator is installed in the front part of the engine compartment on two rubber cushions and is attached to the body with two studs and nuts.
Radiator design
The radiator consists of two vertically located tanks and tubes connecting them. On the tubes there are thin plates (lamellas) that accelerate the heat transfer process. One of the tanks is equipped with a filler neck that is closed with a sealed cap. The neck has a valve and is connected to the expansion tank with a thin rubber hose. In carburetor VAZ 2107 engines, the radiator is provided with a mounting socket for the sensor for turning on the cooling system fan. Models with injection engines do not have such a socket.
The principle of operation of the radiator
Cooling can be carried out either naturally or forcefully. In the first case, the coolant temperature is reduced by blowing the radiator with a counter flow of air while driving. In the second case, the air flow is created by a fan attached directly to the radiator.
Radiator malfunctions
Radiator failure is most often associated with loss of tightness as a result of mechanical damage or corrosion of the tubes. In addition, the tubes may become clogged with dirt, deposits and impurities in the antifreeze, and coolant circulation will be disrupted.
If a leak is detected, you can try to solder the damaged area with a powerful soldering iron using special flux and solder. Clogged tubes can be eliminated by flushing with chemically active substances. Solutions of orthophosphoric or citric acid, as well as some household cleaning products for sewerage, are used as such substances.
Cooling fan
The fan is designed for forced airflow of the radiator. It turns on automatically when the coolant temperature rises to a certain value. In VAZ 2107 carburetor engines, a special sensor installed in the main radiator is responsible for turning on the fan. In injection power units, its operation is controlled by an electronic controller based on the readings of the temperature sensor. The fan is fixed to the body of the main radiator using a special bracket.
Fan design
The fan is a regular DC electric motor with a plastic impeller mounted on the rotor. It is the impeller that creates the air flow and directs it to the radiator lamellas.
The voltage to power the fan is supplied from the generator through a relay and fuse.
Fan faults
The main fan malfunctions include:
- broken wiring;
- relay failure;
- break or short circuit in the stator windings;
- commutator brush wear.
To check operation, the fan is connected directly to the battery.
Radiator and heater tap
The heater radiator is designed to heat the air entering the cabin. In addition, the interior heating system includes a stove fan and dampers that regulate the direction and intensity of the air flow.
Stove radiator design
The stove radiator has the same design as the main heat exchanger. It consists of two tanks and connecting tubes through which the coolant moves. To speed up heat transfer, the tubes have thin lamellas.
To stop the supply of warm air to the cabin in the summer, the heater radiator is equipped with a special tap that shuts off the circulation of coolant in the heating system. The faucet is operated by a cable and a lever located on the front panel.
The principle of operation of the stove radiator
When the heater tap is open, hot coolant enters the radiator and heats the tubes with lamellas. The air flows passing through the heater radiator also heat up and enter the cabin through the air duct system. When the tap is closed, no coolant flows into the radiator.
Radiator and heater valve malfunctions
The most common failures of the radiator and heater tap are:
- leakage caused by mechanical damage or corrosion;
- clogged radiator tubes;
- souring of the faucet locking mechanism.
The stove radiator can be repaired using the same methods as the main heat exchanger. If the tap malfunctions, it is replaced with a new one.
Thermostat
The thermostat maintains the required thermal operating conditions of the engine and reduces its warm-up time when starting. It is located to the left of the pump and is connected to it using a short pipe.
Thermostat design
The thermostat consists of:
The thermoelement is a sealed metal cylinder filled with special paraffin. Inside this cylinder there is a rod that actuates the main thermostat valve. The body of the device has three fittings to which the underwater hose from the pump, the bypass and outlet pipes are connected.
Thermostat operating principle
When the coolant temperature is below 80 0 C, the main thermostat valve is closed and the bypass valve is open. In this case, the coolant moves in a small circle, bypassing the main radiator. Antifreeze flows from the engine cooling jacket through the thermostat to the pump, and then returns to the engine. This is necessary so that the engine warms up faster.
When the coolant heats up to 80–82 0 C, the main thermostat valve begins to open. When the antifreeze heats up to 94 0 C, this valve opens completely, and the bypass valve, on the contrary, closes. In this case, the coolant moves from the engine to the cooling radiator, then to the pump and back to the cooling jacket.
Thermostat malfunctions
If the thermostat fails, the engine may either overheat or be slower to reach operating temperature. This is the result of stuck valves. It is easy to check the functionality of the thermostat. To do this, you need to start a cold engine, let it run for two or three minutes and touch the pipe going from the thermostat to the radiator with your hand. It should be cold. If the pipe is warm, then the main valve is constantly in the open position, which, in turn, will lead to slow warming up of the engine. Conversely, when the main valve blocks the flow of coolant to the radiator, the lower hose will be hot and the upper hose will be cold. As a result, the engine will overheat and the antifreeze will boil.
You can more accurately diagnose a thermostat malfunction by removing it from the engine and checking the behavior of the valves in hot water. To do this, place it in any heat-resistant container filled with water and heat it, measuring the temperature with a thermometer. If the main valve began to open at 80–82 0 C, and fully opened at 94 0 C, then the thermostat is working. Otherwise, the thermostat has failed and needs to be replaced.
Expansion tank
Since antifreeze increases in volume when heated, the design of the VAZ 2107 cooling system provides a special reservoir for accumulating excess coolant - an expansion tank (RB). It is located on the right side of the engine in the engine compartment and has a plastic translucent housing.
Tank design
RB is a plastic sealed container with a lid. To maintain close to atmospheric pressure in the tank, a rubber valve is installed in the lid. At the bottom of the RB there is a fitting to which a hose is connected from the neck of the main radiator.
On one of the walls of the tank there is a special scale for assessing the level of coolant in the system.
Operating principle of the tank
When the coolant heats up and expands, excess pressure is created in the radiator. When it rises by 0.5 atm, the neck valve opens and excess antifreeze begins to flow into the tank. There the pressure is stabilized using a rubber valve in the lid.
Tank malfunctions
All RB malfunctions are associated with mechanical damage and subsequent depressurization or failure of the lid valve. In the first case, the entire tank is replaced, and in the second, you can get by by replacing the lid.
Temperature sensor and fan switch sensor
In carburetor VAZ 2107 models, the cooling system includes a liquid temperature indicator sensor and a fan activation sensor. The first is installed in the cylinder block and is designed to control the temperature and transmit the received information to the dashboard. The fan switch sensor is located at the bottom of the radiator and serves to supply power to the fan motor when the antifreeze reaches a temperature of 92 0 C.
The cooling system of injection engines also has two sensors. The functions of the first are similar to those of the temperature sensor of carburetor power units. The second sensor transmits data to the electronic control unit, which controls the process of turning the radiator fan on and off.
Sensor malfunctions and methods for diagnosing them
Most often, cooling system sensors stop working normally due to problems with the wiring or due to the failure of their working (sensitive) element. You can check their serviceability using a multimeter.
The operation of the fan switch sensor is based on the properties of bimetal. When heated, the thermoelement changes its shape and closes the electrical circuit. Cooling down, it returns to its normal position and stops the flow of electric current. To check, the sensor is placed in a container with water, having previously connected the probes of a multimeter turned on in tester mode to its terminals. Next, the container is heated, controlling the temperature. At 92 0 C the circuit should close, which the device should report. When the temperature drops to 87 0 C, a working sensor will break the circuit.
The temperature sensor has a slightly different operating principle, based on the dependence of the resistance on the temperature of the environment in which the sensitive element is placed. Testing the sensor involves measuring resistance at varying temperatures. A working sensor should have different resistance at different temperatures:
- 20 0 C - 3.5 kOhm;
- 40 0 C - 1.5 kOhm;
- 60 0 C - 0.67 kOhm;
- 90 0 C - 0.25 kOhm.
To check, the temperature sensor is placed in a container of water, which is gradually heated, and its resistance is measured with a multimeter in ohmmeter mode.
Antifreeze temperature indicator
The coolant temperature gauge is installed in the lower left part of the instrument panel. It is a colored arc divided into three sectors: white, green and red. If the engine is cold, the arrow is in the white sector. When the engine warms up to operating temperature and then operates normally, the needle moves to the green sector. If the needle enters the red sector, the engine is overheated. It is highly undesirable to continue moving in this case.
Connecting pipes
The pipes are used to connect individual elements of the cooling system and are ordinary rubber hoses with reinforced walls. Four pipes are used to cool the engine:
In addition, the cooling system includes the following connecting hoses:
- supply and removal of refrigerant from the heater radiator;
- drainage of liquid from the inlet pipeline;
- connections between the radiator neck and the expansion tank.
The pipes and hoses are secured using clamps (spiral or worm). To remove or install them, just loosen or tighten the clamp mechanism with a screwdriver or pliers.
Coolant
The manufacturer recommends using exclusively antifreeze as a coolant for the VAZ 2107. For the uninitiated car enthusiast, antifreeze and antifreeze are one and the same thing. Antifreeze is usually called all coolants without exception, regardless of where and when they were produced. Antifreeze is a type of antifreeze produced in the USSR. The name is an abbreviation for “separate laboratory organic synthesis technology.” Without exception, all coolants contain ethylene glycol and water. The differences are only in the type and quantity of anti-corrosion, anti-cavitation and anti-foam additives added. Therefore, for the VAZ 2107 the name of the coolant is not of great importance.
The danger comes from cheap, low-quality coolants or outright counterfeits, which have recently become widespread and are often found on sale. The result of using such liquids can be not only a radiator leak, but also failure of the entire engine. Therefore, to cool the engine, you should buy coolant from proven and well-established manufacturers.
Find out how to change the coolant yourself:
Possibility of tuning the VAZ 2107 cooling system
You can increase the efficiency of the VAZ 2107 cooling system in various ways. Someone installs a fan from a Kalina or Priora on the radiator, someone tries to better heat the interior by adding an electric pump from a Gazelle to the system, and someone installs silicone pipes, believing that with them the engine will warm up faster and cool down. However, the feasibility of such tuning is highly questionable. The cooling system of the VAZ 2107 itself is quite well thought out. If all its elements are in good working order, the engine will never overheat in the summer, and in winter the cabin will be warm even without turning on the heater fan. To do this, you only need to periodically pay attention to system maintenance, namely:
- fill only high-quality coolant into the engine;
- change the coolant every 50 thousand km with a complete drain and flushing of the system;
- monitor the coolant level and add it if necessary;
- When topping up, never mix antifreeze with antifreeze;
- When replacing faulty elements, use only high-quality certified parts.
Thus, the cooling system of the VAZ 2107 is quite reliable and simple. However, it also needs periodic maintenance, which even an inexperienced car enthusiast can perform.
The cooling system (CO) of the engines of VAZ 2105, 2107 cars is designed to maintain their required operating temperature. The image above shows its diagram.
Main elements of the engine cooling system of VAZ 2105, 2107 cars
— Engine cooling jacket
Cavities around the engine cylinders, in the cylinder head and in the intake manifold through which coolant circulates, removing excess heat from them.
— Pump (water pump)
Designed to ensure forced circulation of liquid through the cooling system. It is a shaft with an impeller rotating on a bearing in an aluminum housing. Driven by a belt drive from the generator pulley and crankshaft. It is recommended to periodically check the belt tension, since if it slips, the pump cannot ensure effective coolant circulation and the engine will fail. The belt deflection under a force of 10 kgf should be within 10-15 mm.
— Radiator
Designed to cool the liquid while the car is moving. Consists of two tanks and two rows of tubes connecting the tanks. It has a plug with inlet and outlet valves on the filler neck. The exhaust valve opens when the liquid becomes very hot and the pressure in the system increases. In this case, part of the liquid is released through it into the expansion tank.
- Expansion tank
Designed to remove highly heated and pressurized coolant from the main system. Has a plug on the filler neck. There is a valve in the plug that opens when the pressure in the system exceeds.
— Thermostat
The thermostat is designed to maintain normal engine temperature conditions by connecting or disconnecting the small and large circles of the cooling system. On a cold engine, the coolant circulates in a small circle (pump, cylinder head, cylinder block, heater, upper part of the thermostat). Her temperature is rising quickly. After warming up the coolant to 80 degrees. The thermostat thermocouple is triggered, opening its bypass valve. The liquid begins to flow through the lower part of the thermostat into the radiator (large circle), where it cools somewhat. The normal and efficient operation of the engine cooling system as a whole depends on the serviceability of the thermostat.
— Cooling fan
With a four-blade impeller combined with an electric motor. Installed on the radiator. Designed for forced cooling of liquid passing through the radiator. It turns on when the temperature sensor (TM-108) installed in the lower radiator tank, on the left, is triggered. It closes its contacts at a coolant temperature above 89-95 degrees, and opens at 84-90 degrees.
— Heater (interior heater radiator)
Designed to heat the car interior. It is part of the small circle of the cooling system, so it warms up first. It has a tap that shuts off the liquid circulating through it. The crane is controlled by a lever from inside the car.
— Pipes and hoses
Designed to ensure coolant circulation throughout the system.
To allow the driver to monitor the temperature state of the engine, there is a dial gauge for the coolant temperature on the instrument panel, connected to a temperature sensor screwed into the engine cylinder head.
Notes and additions
— The operating temperature of the engine, maintained by its cooling system, is in the range of 80-94 degrees.
— When the engine is cold, you should always check the coolant level. The temperature of the engine and, accordingly, the correctness of its operation directly depend on its volume. At an air temperature of 18-20 degrees. The coolant level should be 4 cm above the MIN mark in the expansion tank.
— The frequency of replacing coolant on the engines of VAZ 2105, 2107 cars is 30,000 km.
The cooling system is designedto maintain normal engine thermal conditions.When the engine is running, the temperature in its cylinders rises above 2000 degrees, and the average is 800 - 900oC! If you do not remove heat from the “body” of the engine, then within a few tens of seconds after starting, it will no longer become cold, but hopelessly hot. The next time you can start your cold engine only after it has been overhauled.
The cooling system is needed to remove heat from the mechanisms and parts of the engine, but this is only half of its purpose, although it is the larger half. To ensure a normal working process, it is also important to speed up the warm-up of a cold engine. And this is the second part of the cooling system.
As a rule, a liquid cooling system is used, a closed type, with forced circulation of liquid and an expansion tank (Fig. 25).
The cooling system consists of:
- cooling jackets of the block and cylinder head,
- centrifugal pump,
- thermostat,
- radiator with expansion tank,
- fan,
- connecting pipes and hoses.
To monitor the operation of the system, there is a coolant temperature indicator on the instrument panel. The normal coolant temperature when the engine is running should be between 80-90°C (see Fig. 63).
I risk receiving condemning words addressed to me, but let's imagine that a running engine is still a living organism. The temperature of any living organism is a constant value, and any change in it leads to unpleasant consequences. The same thing happens with the engine; it will not be able to work normally if its thermal conditions do not correspond to the norm.
Engine cooling jacketconsists of many channels in the block and cylinder head through which coolant circulates.
Centrifugal pumpcauses 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 regulated by the deflection of the generator housing (see Fig. 59a) or the tension roller of the engine camshaft drive (see Fig. 11b).
Thermostatdesigned to maintain constant optimal thermal conditions of the engine. When starting a cold engine, the thermostat is closed, and all the liquid circulates only in a small circle (Fig. 25) to warm it up as quickly as possible. When the temperature in the cooling system rises above 80 - 85O, the thermostat automatically opens and part of the liquid enters the radiator for cooling. At high temperatures, the thermostat opens completely and all the hot liquid is directed in a large circle for its active cooling.
Radiatorserves to cool the liquid passing through it due to the air flow that is created when the car moves or using a fan. The radiator has many tubes and "membranes" that create a large cooling surface area.
Well, everyone knows the everyday example of a car radiator. Everyone in the house has radiators (batteries) for central or local heating. They also have a special configuration, and the larger the total area of the complex surface of the radiator, the warmer it is in your house. And at this time, the water in the heating system is actively cooled, that is, it gives off heat.
Expansion tanknecessary to compensate for changes in the volume and pressure of the coolant during heating and cooling.
Fandesigned to forcefully increase the air flow passing through the radiator of a moving car, as well as to create air flow when the car is stationary with the engine running.
Two types of fans are used: a constantly on fan, driven by a belt from the crankshaft pulley, and an electric fan, which turns on automatically when the coolant temperature reaches approximately 100 degrees.
Pipes and hosesserve to connect the engine cooling jacket to the thermostat, pump, radiator and expansion tank.
The engine cooling system also includesinterior heater.Hot coolant passes throughheater radiatorand heats the air supplied to the car interior. The air temperature in the cabin is regulated by a special tap, with which the driver increases or decreases the flow of liquid passing through the heater radiator.
Main malfunctions of the cooling system.
Coolant leakage may appear due to damage to the radiator, hoses, gaskets and seals.
To eliminate the malfunction, it is necessary to tighten the clamps securing the hoses and tubes, and replace the damaged parts with new ones. If the radiator tubes are damaged, you can try to “patch” holes and cracks, but, as a rule, everything ends with replacing the radiator.
Engine overheating may occur due to insufficient coolant level, weak fan belt tension, clogged radiator tubes, or a malfunctioning thermostat.
To eliminate the malfunction, you should restore the fluid level in the cooling system, adjust the fan belt tension, flush the radiator, and replace the thermostat.
Often, engine overheating occurs even when the elements of the cooling system are in working order, when the car moves at low speed and heavy loads on the engine. This happens when driving in difficult road conditions, such as country roads and boring city traffic jams. In these cases, it’s worth thinking about your car’s engine, and about yourself too, by taking periodic, at least short-term, “breaks.”
Be careful while driving and do not allow the engine to run in emergency mode!
Remember that even a one-time overheating of the engine disrupts the structure of the metal, and the life expectancy of the “heart” of the car is significantly reduced.
Operation of the cooling system.
When operating your vehicle, you should periodically look under the hood. Even if you are a philologist by training and have not hammered a single nail in this life, you will still be able to see something and take timely measures to extend the life of your car.
If coolant level in the expansion tank has dropped or there is no liquid at all, then first you need to top it up, and then figure out (on your own or with the help of a specialist) where it went.
During engine operation, the liquid heats up to a temperature close to the boiling point, which means that the water included in its composition will gradually evaporate. If over six months of daily use of the car the level in the tank has dropped slightly, then this is normal. But if yesterday the tank was full, and today there is only the bottom in it, then you need to look for a coolant leak.
Leakage of fluid from the system can be easily identified by dark spots on the asphalt or snow after a more or less long period of parking. Once you open the hood, you can easily find the location of the leak by comparing wet marks on the asphalt with the location of the cooling system elements under the hood.
It is necessary to monitor the fluid level in the tank at least once a week and if there are leaks, then it is necessary to top up, find and eliminate the reason for the decrease in level. In other words, you need to put your engine cooling system in order. Otherwise, he may become seriously “ill” and require “hospitalization.”
Almost all domestic cars use a special low-freezing liquid called TOCOL A-40 as a coolant. The number (minus 40°) shows the temperature at which the liquid begins to freeze (crystallize). In the far north it is used TOSOL A-65, and accordingly it will begin to freeze at a temperature of minus 65o.
TOSOL A-40 is a mixture of water with ethylene glycol and additives. This solution combines a lot of advantages. In addition to the fact that it begins to freeze only after the driver himself has already frozen (just kidding), TOSOL also has anti-corrosion, anti-foaming properties and practically does not produce deposits in the form of ordinary scale, since it contains pure distilled water. That's why Only distilled water can be added to the cooling system.
When operating a vehicle, it is necessary control not only the tension, but also the condition of the water pump drive belt, since its breakdown on the road is always unpleasant. It is recommended that you carry a spare belt with you. If not you yourself, then one of the “gentlemen” on the road will help you change it.
The coolant may boil and cause engine damage if it fails. fan electric drive sensor. Since the electric fan has not received a command to turn on, the liquid continues to heat up, approaching the boiling point, without any cooling assistance. But the driver has before his eyes a device with an arrow and a red sector! Moreover, almost always when the fan is turned on, some vibration and a little additional noise are felt. There would be a desire to control, but there will always be ways.
It is especially unpleasant when the engine “boils” while driving off-road at low speed in the hot summer. Therefore, there is practical advice for those who like to explore the outback of their native land and also know how to hold a screwdriver in their hands.
If you add another toggle switch in the car interior (or use a free one), with which you can manually turn on the electric fan of the cooling system, then a failed sensor will not interrupt your trip. By monitoring the coolant temperature on the device, you can decide when to turn the fan on and off.
If on the road (or more often in a traffic jam) you notice that the coolant temperature is approaching critical 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 - the interior heater radiator. Fully open the heater tap, turn on the heater fan at full speed, lower the door windows and “sweat” home or to the nearest car service center. But continue to closely monitor the engine temperature gauge needle. If it enters the red zone, stop immediately, open the hood and “cool down”.
Can cause trouble over time thermostat, if it stops releasing liquid through a large circulation circle. It is not difficult to determine whether the thermostat is working. The radiator should not heat up (determined by hand) until the coolant temperature gauge needle reaches the middle position (thermostat closed). Later, hot liquid will begin to flow into the radiator, quickly heating it, which indicates the timely opening of the thermostat valve. But if the radiator continues to remain cold, then there are two ways. Tap on the thermostat housing, maybe it will open after all, or immediately, mentally and financially, prepare to replace it.
Immediately “surrender” to a mechanic if you see droplets of liquid on the oil dipstick that have entered the lubrication system from the cooling system. This means it is damaged cylinder head gasket and the coolant enters the engine oil pan. If you continue to operate the engine with oil half consisting of antifreeze, the wear of engine parts will become catastrophic. And this, in turn, is already associated with very expensive repairs.
Water pump bearing does not break “suddenly”. First, a specific whistling sound will appear from under the hood, and if the driver “thinks about the future,” he will replace the bearing in a timely manner. Otherwise, it will still have to be changed, but after being late for the airport or for a business meeting, due to a “suddenly” broken down car.
Each driver must know and remember that When the engine is hot, the cooling system is under high pressure! If your car’s engine overheats and “boils,” then, of course, you need to stop and open the hood of the car, but I do not recommend opening the radiator cap. This will do practically nothing to speed up the engine cooling process, but you can get severe burns.
Everyone knows what a clumsily opened bottle of Champagne means for smartly dressed guests. In a car everything is much more serious. If you quickly and thoughtlessly open the cap of a hot radiator, a fountain will fly out, but not of wine, but of boiling antifreeze! In this case, not only the driver, but also nearby pedestrians may suffer. Therefore, if you ever have to open the radiator cap or expansion tank, you should first take precautions and do it slowly.
From this we can conclude that the driver of that foreign car not only had little driving experience, but he also had not read this book! However, this is his problem; this should not happen to our reader!
All cars of the “Classic” family from AvtoVAZ were equipped with an interior ventilation and heating system. In many ways, they were similar in design and simple, since they did not use modern air conditioners. And although it is impossible to wait for coolness in the “Classics” cabin in the summer, the heating system will not allow you to freeze in winter.
The heating system of the VAZ 2104, like the other models of the family, was derived from the liquid cooling system of the power plant. To make it clear, this system includes two radiators, which remove heat from the coolant passing through them.
But one of the radiators is the main one; it regulates the temperature of the liquid, so heat is removed from it into the environment so that heat exchange is carried out efficiently. It is installed in front of the car, under the radiator grille.
The second radiator provides interior heating. It also carries out heat exchange with heat being released to the air, but this air is supplied to the cabin, and this ensures its heating.
But this radiator is small in size, so to effectively heat the interior, an entire system is used to ensure forced air supply to the radiator, removal of already heated air to a certain area of the cabin, while it is possible to shut off the supply of heated liquid to the radiator of the VAZ-2104 stove. After shutting down, the system can continue to operate, providing cold air into the cabin - which is provided by the cabin ventilation system in the summer.
Heating and ventilation system design
For clarity, a diagram of the VAZ-2104 stove is provided
So, under the position 1 there is a resistor for changing the fan speed. The base of the stove consists of a fan housing 2 and blower fan guide 3 . They are connected to the upper part of the body with brackets 4 . The upper part of the case is the radiator shroud 5 . An air intake hatch is installed on top of it 6 .
There is a radiator inside the top part 8 , and to ensure a tight fit, a foam pad is used 7 . This radiator is connected to the cooling system via metal pipes 9 . A valve 10 for supplying liquid to the radiator is installed on the incoming pipe.
The stove fan consists of an impeller 11 and electric motor 12 . The fan is secured to the housing using a bracket 13 , and to prevent its vibration, it is pressed with a pillow 14 .
On the lower part of the body there are dampers for supplying warm air to the front doors 15 , as well as a cover for air supply to the foot area 16 .
But this is only the design of the stove; in order for the VAZ 2104 interior to be heated properly, additional mechanisms are attached to it.
The following pictures show the remaining elements of the system
Design of the heating system VAZ 2104
Heating system side view
Under the designations 1 And 2 showing left and right air ducts with left 4 and right 5 nozzles. Position 3 indicates the windshield air duct. Control Panel - 6 , with crane control handles 9 , control of the inflow cover 10 and control of the heating of the side and windshields 11 . Under position 12 The air distribution cover lever is located.
Next come the elements of the stove itself: 13 – fan housing with impeller 14 and electric motor 15 , windshield flap 16 , fan speed control resistor 17 , fan housing guide 21 , liquid supply control valve 22 , radiator housing 23 , radiator 25 with gasket 24 , air supply cover fastening elements 26 .
Position 18 – control rod for the side heating flap, 19 – heated side window flap, 27 – heater draft, 28 – air intake grille, 29 – car hood, 30 – air supply box, 31 - windshield.
Heating scheme
Air flow diagram of the VAZ-2104 heating system
Cold air is supplied into the heating system through the air intake grille 28 installed near the windshield from outside the car. Further heating of the VAZ-2104 can be carried out in three directions, which are selected by the control system:
1 – heated windshield, this direction is indicated in red. With this scheme, air enters through the hatch 7 into the air supply box 30 for cleaning from dust and water droplets. Then it moves through the radiator 25 , where heat is removed from the coolant, as well as the fan housing 13 , from where it enters the windshield heating duct 3 .
2 – heated side windows at the front, this direction is indicated in blue. Here the air also enters through the hatch into the box, then into the radiator casing 23 , and then enters the left and right air ducts 1 And 2 .
3 – heating of feet, this direction has a green designation. Air enters the cabin, as in other directions, but after the radiator casing it enters the internal ventilation duct 8 .
System management
In the VAZ-2104, the interior heating is controlled by the control panel handles, each of which ensures the closing and opening of one or another element.
Yes, the top handle 9 ensures opening and closing of the radiator valve 22 . It regulates the amount of liquid that will enter the radiator.
Middle handle 10 The air supply hatch 7 is opened and closed, which regulates the amount of fresh air supplied from outside the car.
Lower handle 11 regulates the position of the damper 16, which distributes the air flow through the air ducts.
There is one feature of air flow distribution control. When the damper position 16 In order to blow the windshield, the heated flaps of the side windows are completely closed. Conversely, when the air flow is blocked by the flap on the windshield, the air is directed only to the side windows.
This phenomenon is due to the fact that the windshield damper lever is connected to the side air duct damper lever. Therefore, to simultaneously heat the windshield and side windows, the damper control handle must be placed in the middle position.
Heating of the VAZ-2104 is carried out in 4 ways:
- Heated windshield (Middle and lower control panel handles are moved to the right all the way);
- Heated side windows (the middle handle is moved to the right, and the bottom handle is moved to the left all the way);
- Heating of feet (upper handle – to the right all the way, air distribution cover of the heater housing is lowered down);
- Supply of hot air from outside through lowered windows (sounds like a joke, but this is indicated in the technical documentation for the car);
This car is also equipped with exhaust ventilation to remove air from the passenger compartment. Unfortunately, there is no diagram of this ventilation specifically for the VAZ-2104, but it is identical to the VAZ-2105 model, which is presented below:
So, 1 - this is a car heating system, 2 – decorative grille with a rubber valve hidden underneath it 3 , through which air can escape when the windows are closed. The same valve prevents dust and moisture from entering the interior.
Correct control of the heating and ventilation system of the VAZ-2104
Correct control depends on the weather outside. In summer, when it is hot and there is no need to supply hot liquid to the radiator:
- The lower handle of the system control panel is moved to the right all the way to open the air supply cover and supply fresh air to the cabin;
- Air flow distribution is carried out by the middle handle;
- To ensure a greater flow of fresh air, you can turn on the fan;
When it's cold outside:
- Move the top handle all the way to the right to ensure the supply of hot liquid to the heater radiator;
- Turn the nozzles of the side air ducts so that warm air flows onto the side windows in the area where the side mirrors are located;
- To warm your feet, you need to lower the heater housing cover down;
If the windshield is covered with frost and needs to be defrosted quickly:
- Move the top handle to the right all the way for maximum fluid supply to the heater radiator;
- Middle handle - all the way to the left to shut off the air supply from outside the car;
- The lower handle - to the right all the way to ensure the supply of warm air only to the windshield;
Video - stove VAZ 2104
