Device Features
Closed-type cooling system, with forced circulation of the coolant, with expansion tank (pic. 9-28).
Pic. 9-28. Cooling system:
1 - steam outlet pipe of the expansion tank; 2 - plug of the expansion tank; 3 - steam outlet hose of the engine; 4 - radiator inlet hose; 5 - expansion tank; 6 - steam outlet pipe of the radiator; 7 - radiator; 8 - upper radiator mounting cushion; 9 - electric fan; 10 - bottom cushion; 11 - radiator outlet hose; 12 - filling hose; 13 - thermostat.
The centrifugal type coolant pump is driven by a V-belt from the crankshaft pulley.
The cooling system also has a radiator 7 with an expansion tank 5, a thermostat 13, a coolant temperature sensor, a cooling jacket and connecting hoses.
When the engine is running, the liquid heated in the cooling jacket through the outlet pipe enters the radiator or thermostat, depending on the position of the thermostat valves. Next, the coolant is sucked in by the pump and re-supplied to the engine cooling jacket.
The cooling system has a built-in double-acting thermostat, the valve opening start temperature is 83°C.
Checking the level and density of liquid in the cooling system
The correct filling of the cooling system is checked by the level of liquid in the expansion tank, which, on a cold engine (at 15-20°С) should be 25-30 mm above the mark «MIN», printed on the expansion tank.
Warning: It is recommended to check the fluid level on a cold engine, since when heated, its volume increases and in a warm engine, the fluid level can rise significantly.
If necessary, check the density of the coolant with a hydrometer, which should be 1.078-1.085 g/cm3 for liquid Antifreeze A-40.
If the liquid level in the tank is below normal, and the density is above normal, then pour distilled water. At normal density, add liquid of the brand that is in the cooling system.
Engine Coolant Replacement
When changing the fluid, do the following:
- set the heater control to position «Warm»;
- drain the coolant through the two drain holes by unscrewing the plugs from the lower tank of the radiator and the cylinder block, removing the plug from the expansion tank. Remove the rest of the liquid from the expansion tank by disconnecting the tank and lifting it above the radiator;
- to flush the cooling system, fill the system with clean water, start the engine and let it run until the lower radiator tank warms up. With the engine running at idle, drain the water through the drain holes, stop the engine and cool it down;
- repeat washing according to the above method;
- after flushing, wrap the plugs and fill the system with fresh coolant 25-30 mm above the mark «MIN» on the expansion tank.
Fill the liquid through the filler neck of the expansion tank. Put the plug, start the engine and let it idle for 1.5-2 minutes. Stop the engine and add fluid to the expansion tank if necessary.