The cooling system is closed liquid, includes a water pump driven by an auxiliary belt from the crankshaft, an electrically driven radiator fan, a radiator, an expansion tank, a thermostat, a heater radiator, hoses and switches.
The vane type water pump is mounted on the front of the cylinder block.
The thermostat, depending on the temperature of the coolant, automatically turns on or off the radiator of the cooling system, passing liquid through the radiator or bypassing it.
When starting a cold engine, no coolant enters the radiator because the main thermostat valve is closed and the bypass valve is open. The coolant circulates through the jacket of the block and the cylinder head, then again enters the pump. This ensures a quick warm-up of a cold engine.
When the coolant reaches the thermostat opening temperature, the solid wax thermostat filler expands, compresses the rubber insert and pushes the piston out. In this case, the main valve will open completely, and the bypass valve will completely close. Hot coolant passes through a hose to the radiator and is cooled by oncoming air.
The radiator fan is switched on by a thermal switch depending on the temperature of the coolant.
The cooling radiator is closed with a sealed cover. The cap creates increased pressure in the cooling system, which raises the boiling point of the coolant, and a higher boiling point of the coolant increases the efficiency of the radiator. If the pressure in the system exceeds the set value, the safety valve in the cap opens and releases the coolant through the hose into the expansion tank. When cooled, the coolant flows from the reservoir back into the radiator.
The expansion tank has two functions: it serves as a container for collecting heated coolant and for replenishing the cooling system.
The air supplied by the ventilation system to the passenger compartment can be heated or cooled, depending on the comfort conditions chosen by the driver and passengers. The heating and air conditioning systems are separate, but their units and assemblies are located in the passenger compartment in a common housing under the instrument panel. The entire flow of air supplied to the passenger compartment is directed for heating or cooling through the same air ducts. The temperature and air flow rate are controlled by the same controls.
The heat generated during engine operation is transferred by the coolant to the heater radiator located in the passenger compartment. The air flow from the passenger compartment fan passes through the radiator and is heated by the heat of the coolant.
If the air coming out of the ventilation grilles does not heat up, the following reasons are possible:
- the thermostat is constantly open, as a result of which the coolant does not heat up to the required temperature and does not transfer sufficient heat to the heater core. In this case, replace the thermostat;
- clogged coolant supply hoses to the heater core. Check the temperature of the hoses near the bulkhead of the engine compartment, they should be hot. If one of the hoses is cold, then there is a blockage in the hoses or the heater core. Disconnect the hoses from the fittings on the partition of the engine compartment and, in turn, supplying water under pressure to the fittings, flush the hoses and the heater radiator;
- If flushing the heater core does not give positive results, replace the heater core.
Coolant
Attention! Do not allow coolant to come into contact with clothing or body paintwork. Otherwise, rinse the surface with plenty of water.
Attention! Collect and dispose of the drained coolant.
The cooling system must be filled with coolant all year round. The coolant is a 50:50 mixture of ethylene glycol antifreeze and distilled water. In cold climates, the antifreeze content of the coolant may be increased according to the fluid manufacturer's recommendations, but should not exceed 70%.
The optimal concentration of antifreeze eliminates freezing of the liquid in the engine block, the formation of corrosion and lime deposits, and also increases the boiling point of the coolant.
Replacing the coolant with flushing the cooling system must be done once every two years. Before filling the cooling system, check the condition of the hoses and their fittings. During the operation of the car, the coolant level should not change. A rapid drop in the coolant level indicates a leak and needs to be repaired. Check the condition of the radiator, water pump, hoses, connections and drain plugs for signs of leakage. If no leaks are found, have a service station check the opening pressure of the valve in the radiator cap.
The coolant must also be replaced after any work has been carried out on the elements of the cooling system with the coolant drained. If the cylinder head, head gasket, radiator or oil heat exchanger was replaced during the repair, fill the cooling system with fresh coolant. This is due to the fact that the anti-corrosion additive in the coolant is deposited during engine operation and creates anti-corrosion protection. In used coolant, anti-corrosion additives are not active enough to form a protective layer on newly installed parts.