Cooling system: 1 - hose for draining coolant from the heater radiator; 2 - hose for supplying coolant to the heater radiator; 3 - hose for draining fluid from the engine radiator; 4 - expansion tank hose; 5 - expansion tank; 6 - steam outlet hose of the engine radiator; 7 - thermostat; 8 - hose for supplying fluid to the engine radiator; 9 - radiator electric fan; 10 - engine radiator; 11 - radiator drain plug; 12 - coolant pump; 13 - inlet pipe of the coolant pump.
The engine cooling system is liquid, closed type with forced circulation of the coolant and an expansion tank.
The engine cooling system uses special liquids based on a mixture of water and ethylene glycol. They have a low freezing point and a high boiling point. In addition, thanks to the complex of added additives, the coolant prevents corrosion of the channel walls, does not foam, and prolongs the life of the coolant pump seal.
The circulation of liquid in the system is provided by a centrifugal pump installed in the cylinder block. The pump drive is dried by a toothed timing belt.
The cooling system consists of two so-called circulation circles. The small circle does not include the engine radiator, and the liquid washes only the cylinder block and cylinder head, and also flows through the heater radiator. The heater radiator is built into the engine cooling system and is designed to heat the passenger compartment by circulating hot coolant through it. When driving in a large circle, the coolant passes through the engine radiator, where it is cooled by the oncoming air flow. The thermostat controls the direction of fluid flow in the engine cooling system.
If the air flow is insufficiently intense, the radiator is cooled by an electric fan. It is installed behind the engine radiator and is activated by a signal from the electronic engine control unit. An additional resistor is built into the power supply circuit of the fan motor.
To compensate for the thermal expansion of the liquid, an expansion tank is installed in the cooling system. Inlet and outlet safety valves are placed in the tank plug, which allows maintaining the optimal pressure in the system when the liquid overheats, and also compensates for the vacuum when it cools.