2. A tubular-plate radiator is installed in the front part of the car. It consists of upper and lower tanks connected by a core (tubes with heat-exchange surfaces in the form of ribs). Models with a variator or automatic transmission are equipped with an oil cooler for cooling the working fluid of the variator or automatic transmission (ATF), which is located in the lower tank of the radiator.
3. Excess coolant (the result of the increase in the volume of liquid when it is heated in the cooling system) enters the expansion tank. The liquid from the expansion tank returns to the radiator when (the temperature in the system drops, as a result of which the radiator is always filled with liquid and its loss is excluded.
4. The radiator cap has two safety valves - steam and vacuum. The steam valve opens to release steam through the outlet pipe (hose) when the pressure inside the cooling system exceeds the maximum permissible value (coolant temperature 110 - 120°C, pressure 74 - 103 kPa). The air (vacuum) valve opens to reduce the vacuum that occurs in the cooling system after the engine has stopped and the temperature has dropped (pressure - 5 kPa or less). Opening the valve allows the coolant to return to the system from the expansion tank.
5. The pump is of a centrifugal type, installed in the front part of the cylinder block and driven by a timing belt.
6. The thermostat is installed in the engine intake manifold. The solid filler inside the thermostat expands when heated (opening the valve) and contracts when cooled (closing the valve). The thermostat valve begins to open at the target temperature (above 82°C). At a temperature of about 95°C, the valve is fully open.
[The material was borrowed from the website mitsubishiman]