6. Engine cooling system
Position of valves of the thermostat at various temperature of cooling liquid
I – from a head of the block of cylinders;
1 – main valve,
The engine cooling system – liquid, the closed type with compulsory circulation. On the cold engine liquid circulates on "a small circle". Shirts of cooling of the block and a head of cylinders of the engine, the pump of cooling liquid, the thermostat, and also a heater radiator when its crane is open enter it. At achievement of temperature of liquid 80-85 ° two valves of the thermostat come into action, blocking a small circle and discovering liquids a way through a radiator of the engine which is intensively blown by a counter flow of air at the movement, and also by means of the electric fan.
The radiator consists of two horizontal tanks connected among themselves by tubes. For the best heat sink of a plate napressovana on them. Liquid moves in a radiator through the top branch pipe, and is taken away through lower.
Passing through a radiator, liquid is cooled then again comes to the engine. Change of volume of cooling liquid at its heating or cooling compensates a broad tank. For visual control of level of cooling liquid the tank is made of translucent polyethylene.
Tightness of system is provided inlet and final with valves of a stopper of a jellied mouth of a radiator. On the hot engine the final valve supports elevated pressure in system. At the expense of it liquid boiling temperature increases. At its cooling the inlet valve opens, passing a part of liquid from a broad tank in a radiator and by that compensating reduction of volume of liquid.
In a stopper of a broad tank there is an opening therefore in his internal cavity pressure always atmospheric.
Pump of cooling liquid of centrifugal type. The pump housing – aluminum, folding, consists of two parts. The roller of the pump rotates in the two-row bearing of the closed type which is not demanding service. On the forward end of a shaft напрессован a pump drive pulley flange – a maple belt from a pulley of a bent shaft of the engine.
Recently cars are completed with radiators with plastic tanks and an aluminum core.
It is not recommended to fill in water in the engine cooling system. It leads to scaling on walls of system, corrosion of details, to deterioration in heat exchange and reduction of a resource of consolidation of the pump.