Coolant circulation is controlled by a thermostat. While the engine is not warmed up, the coolant circulates only in the cylinder head, in the cylinder block and in the heater core.
As the temperature rises, the liquid cooling system thermostat opens and directs coolant flow to the radiator. The coolant is supplied by a water pump.
The coolant flows through the radiator from top to bottom and is cooled by oncoming air passing through the cooling fins.
For additional cooling of the liquid, an electric radiator fan is installed.
As soon as the temperature of the coolant goes beyond certain limits, the relay turns on the said electric fan.
As the coolant temperature drops, the electric fan switches off.
The expansion tank in cars with petrol engines up to 5/99 is located in the engine compartment on the right side, when viewed in the direction of travel, directly at the radiator.
In cars with petrol engines from 6/99, as well as in cars with diesel engines, the expansion tank is located on the right stiffener and is connected to the radiator with two hoses.
It performs the function of a coolant reservoir and accumulates the coolant that increases in volume when heated, giving it back to the circulation circuit after the engine has cooled.
Replenishment of the coolant in the system is carried out through the expansion tank.
Attention! When working on the cooling system, be sure to remember that it is not allowed to get coolant on the ribbed belt. Ethylene glycol contained in the coolant can damage the fabric of the belt so much that it breaks after a certain period of operation, which in turn will cause serious engine damage.
Attention! Before starting work in the engine compartment, especially near the radiator fan, be sure to remove the fuse or disconnect the electric fan power plug. The electric fan, under the influence of heat accumulated in the engine compartment, and the ignition is not turned off, can automatically turn on. Risk of injury or injury!