General provisions
Engine cooling system - liquid, closed (sealed), with forced circulation of coolant.
The system is filled with all-weather coolant TOSOL A-40, which has anti-corrosion and anti-foaming additives. The liquid thickening start temperature is not higher than -40°С.
The amount of coolant in the cooling system is (approx. 9.6 l), so that after the engine has warmed up to a temperature of 80-90°C and after it has cooled down, the coolant level in the expansion tank is set at least 3 cm above the MIN·mark (minimum). The plant has set the period for replacing the coolant after two years of operation or after 60,000 km of the car's run. During this period, the coolant retains all the necessary properties to ensure the normal operation of the cooling system.
In case of unexpected loss of antifreeze (for example, due to a leak or when working on the engine associated with the separation of elements of the cooling system, etc.) the plant recommends adding TOSOL A-40 to the cooling system so that with the onset of the cold season there is no doubt about the freezing temperature of the coolant filled into the system.
The thermal regime of the engine is considered normal in the case in which the temperature of the coolant in the engine is in the range from +80 to +100°C (the arrow of the temperature indicator is at the beginning of the red field of the scale). The transition of the arrow to the red zone of the scale indicates an increased temperature regime of the engine. Under normal driving conditions, this can be caused by a problem with the cooling system (insufficient coolant, thermostat malfunction, loose fan belt). With a working cooling system, the temperature regime rises due to difficult driving conditions (climbing steep hills, driving on sand, towing, etc.).
The transition of the arrow to the right side of the red field of the scale indicates excessive overheating of the engine. In this case, you must immediately stop driving without stopping the engine (it should run at idle). If overheating persists, turn off the engine after finding out the cause of overheating and eliminate it.
To drain the antifreeze in the cooling system, drain plugs are installed: one in the left corner of the lower radiator tank, the other in the cylinder block, to the left in the direction of the car.
Elements of the cooling system
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1. Heater radiator. 2. Pipe for supplying liquid to the heater radiator. 3. Hose for draining liquid from the carburetor mixing chamber heating system. 4. Hose for supplying fluid to the carburetor mixing chamber heating system. 5. Fluid supply hose to thermostat bypass valve. 6. Subsea radiator hose. 7. Expansion tank. 8. Expansion tank tube. 9. Expansion tank plug. 10. Pipe for draining fluid into the expansion tank. 11. Radiator cap. 12. Inlet vent valve plug. 13. Outlet valve plug. 14. Radiator mounting bracket. 15. Upper radiator block. 16. Radiator cooling tube. 17. Radiator cooling plate. 18. Fan. 19. Fan drive belt. 20. Fan shroud. 21. Radiator cushion. 22. Lower radiator tank. 23. Radiator outlet hose. 24. Water pump. 25. Generator. 26. Underwater hose of the water pump. 27. Thermostat. 28. Branch pipe for draining fluid from the heater radiator. 29. Hose for supplying fluid to the heater radiator. 30. Hose for draining fluid from the heater radiator. 31. Heater tap. 32. Bracket for fastening the expansion tank. 33. Internal and external collars of fastening of a broad tank. 34. Details of fastening of a broad tank.
The radiator is a vertical tubular-plate radiator with two rows of brass tubes 16 and tinned steel plates 17. The upper 15 and lower 22 tanks and their bottoms are made of brass and are connected by soldering to each other, as well as to tubes and plates. Plates and brackets 14 for fastening the radiator and casing 20, fan 18 are steel and are connected to the flanges of the radiator bottoms by contact welding. The radiator is mounted on body brackets on two rubber cushions 21 and fastened with two bolts through steel spacers and rubber bushings.
Radiator plug 11 has outlet 13 and inlet (ventilation) 12 valves. When heated, the coolant, expanding, flows through the vent valve and outlet pipe 10 into the expansion tank 7. The liquid level in it rises. When the temperature drops, the reverse process occurs.
When the coolant boils, the capacity of the ventilation valve openings is not enough and, under the influence of an increased pressure drop on the valve plate, it closes, separating the cooling system from the expansion tank. The pressure in the system increases, providing a higher temperature of the coolant and, therefore, more heat transfer through the radiator.
With an increase in pressure in the system above 0.5 kgf / cm2 The exhaust valve opens and the coolant is discharged into the expansion tank. In this case, excess steam can escape into the atmosphere through a slot in the rubber gasket of plug 9 of the expansion tank.
Expansion tank 7 - plastic, translucent, attached to the bracket 32 of the body with two clamps 33, one of which (outer) spring loaded.
The expansion tank serves to compensate for changes in the volume of the coolant that occur when its temperature changes during engine operation, to control the amount of coolant in the system, and also contains some reserve of liquid for its natural loss and possible losses during operation.
The expansion tank is connected to the radiator with a plastic tube 10, which is put on in a heated state on the pipes of the tank and the radiator filler neck and fastened with band clamps.
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1. O-ring seal. 2. Stuffing box. 3. Bearing outer ring. 4. Water pump cover. 5. Fan hub. 6. Water pump roller. 7. Locking screw. 8. Gland seal. 9. Water pump housing. 10. Water pump impeller. 11. Water pump inlet. 12. Thermostat bypass. 13. Upper thermostat housing. 14. Diverter (to the pump) thermostat tube. 15. Lower thermostat housing. 16. Thermostat piston. 17. Foster (from the radiator) thermostat tube. 18. Main valve seat. 19. Sealant. 20. Main valve. 21. Rubber insert. 22. Main valve spring. 23. A glass of a thermosensitive element. 24. Solid filler. 25. Rack bypass (bypass) valve. 26. Bypass valve. 27. Bypass valve spring.
Water pump - centrifugal type with a cast iron impeller 10. The end of the impeller, in contact with the sealing ring 1 of the stuffing box, is subjected to HDTV hardening.
Housing 9 and cover 4 of the pump are cast from aluminum alloy. The body is cast integrally with the inlet pipe 11 and the flange for connecting the pipe that drains liquid from the heater radiator.
The pump stuffing box is non-separable, it consists of a body 2, a rubber cuff 8, put on two telescopic brass clips, and an o-ring 1 made of graphite composition, pressed against the end of the impeller by a cylindrical spring through the side walls of the cuff. The seal is pressed into the water pump cover.
The pump bearing is ball double-row, non-separable. The role of the inner race of the bearing is performed by roller 6, on which the impeller is pressed on one side, and on the other, the hub 5 of the fan drive pulley and the water pump. The bearing is installed in the pump cover and fixed in it with a locking screw 7. The bearing is filled with grease during assembly and no further lubrication is required.
Fan - plastic, four-bladed. Wing profile blades unevenly spaced along the hub. The fan is attached to the hub together with the drive pulley with three bolts. To increase the efficiency of the fan is equipped with a steel casing, which is attached to the radiator and has a cutout in the lower part for mounting and assembly.
The fan and water pump are driven by a V-belt from the crankshaft pulley.
The belt tension is carried out by turning the generator and is controlled by the amount of deflection. The deflection should be within 10-15 mm with a force of approximately 10 kgf.
Thermostat and cooling system operation
The required thermal regime of the engine is provided by a thermostat. The non-separable design thermostat has two inlets: one (bottom 17) connected to the lower radiator tank, and the other (top 12) - with a pipe that drains coolant from the block head to the radiator inlet. The outlet pipe 14 of the thermostat is connected to the inlet to the pump.
The thermosensitive element of the thermostat consists of a glass 23 with a rubber insert 21 rolled into it, while a solid filler 24 is placed between the walls of the glass and the insert, and inside the insert there is a polished steel piston 16 fixed in the seat post 18 of the main valve 20. The main valve is put on the glass thermoelement and is pressed along with it to the seat by a conical spring 22. Two posts 25 of the bypass valve 26 are fixed on the main valve, which is supported on them in the uppermost position by the spring 27, which abuts against the bottom of the thermosensitive element cup. The seat of the main valve assembly with a temperature-sensitive element, springs 22, 27 and valves 20, 26 is rolled through a rubber seal 19 in two housings: upper 13 and lower 15.
When the coolant temperature is below 80 C, the main valve closes the fluid outlet from the radiator. At the same time, the bypass valve is open and the coolant circulates in a small circle, bypassing the radiator, which ensures that the engine warms up quickly.
At temperatures above 80°C, the solid filler, expanding, compresses the rubber insert, forces it to come off the piston and, overcoming the resistance of the main valve spring, moves the thermoelement cup up together with the main valve. The bypass valve also moves up and is pressed against the end of the inlet pipe by a spring. In this case, the direct passage of fluid from the head of the block to the pump (in a small circle) closes and the liquid begins to circulate through the radiator, cooling intensively.
At temperatures above 94°C, the main valve is fully open, the bypass valve is closed and all liquid passes through the radiator; at intermediate temperatures (80-94°С) the coolant circulates through both the main and bypass valves, the degree of opening of which ensures the gradual mixing of the cooled liquid in the radiator to the hotter liquid leaving the engine. This achieves the best operating conditions for the engine in terms of temperature.
The engine cooling system includes a body heater 1 and a carburetor throttle body heating system, the liquid into which is supplied through hose 4 from the inlet pipe heating jacket and is discharged to the pump through hose 3 and the outlet pipe 31 of the heater.
The liquid enters the heater from the head of the block through pipe 2 and tap 31, and is discharged to the pump through hose 30 and steel pipe 28.
Cooling system with electric fan
On VAZ-2103 vehicles, instead of a fan located on the water pump roller and driven by a V-belt from the engine crankshaft pulley, a fan driven by an individual electric motor is installed in the engine cooling system.
The electric motor assembly with the fan is installed on three rubber bushings with spacers in a casing of a special design. The casing is attached at three points directly to the radiator, which, unlike the conventional type radiator, has modified brackets for attaching to the body.
The electric fan is turned off automatically using a sensor installed in the lower radiator tank and a relay. The calibration of the sensor is selected in such a way that it turns on (when checking on a special stand) at a temperature of 92°C, and turns off at 84±2°C.
It should be remembered that the coolant temperature indicator sensor is installed in the cylinder head and its temperature conditions during engine operation are different. Therefore, it is impossible to check the response temperature of the electric fan switch-on sensor using a car instrument. Verification must be carried out (if necessary) at service stations using special equipment and instruments.