Pic. 9. Connecting the radiator of the cooling system: 1 — stopper of a broad tank; 2, 3, 12, 14 and 16 hoses; 4 - left tank of the radiator; 5 - electric fan impeller; 6 radiator shroud; 7 radiator core; 8 - sensor for turning on the electric fan; 9 - drain plug; 10 - electric motor; 11 - outlet pipe of the cylinder head; 13 - inlet pipe of the heater; 15 thermostat; 17 - expansion tank.
Hot liquid is discharged from the cylinder head to the radiator or, bypassing it (depending on the position of the thermostat valves), enters the pump, from which it is sent to the cooling jackets of the block and cylinder head.
The engine cooling system includes a body interior heater, into which liquid enters from the cylinder head through the inlet pipe 13 (see fig. 9) and discharged to the pump through the outlet pipe 1 (see fig. 8) suction pipe 2, as well as heating the inlet pipe, from which it is discharged through hose 3 to the pump. The pump is driven by a toothed belt 6 from the toothed pulley of the crankshaft.
To compensate for changes in the volume and pressure of the coolant, there is an expansion tank, which is connected by hoses to a thermostat in the fluid inlet area from the radiator and to the radiator.
Coolant pump
Centrifugal type, driven by engine toothed belt, mounted on cylinder block 3 (pic. 10). The roller 5 is placed in the housing 2 on a double-row ball bearing 8, which is locked with a screw 1. A toothed pulley 9 and an impeller 4 are pressed onto the roller, which is sealed with an oil seal 7 and an o-ring 6 made of graphite composition.
The coolant pump is interchangeable with the pump of the VAZ-2108 car.
Electric fan
Interchangeable with the electric fan of the VAZ-2103 engine. The fan is turned on and off depending on the coolant temperature by a sensor screwed into the right radiator tank.
Radiator
Prefabricated, aluminum, with plastic tanks. Radiator core - with two rows of horizontal tubes. The radiator is mounted on rubber pads. The left radiator tank is connected by a hose to the expansion tank. The expansion tank is closed with a stopper with valves. The plug is interchangeable with the plug from the expansion tank of the VAZ-2108 engine. The pressure of the beginning of the opening of the exhaust valve is not less than 0.12 MPa, the intake valve - 0.003-0.013 MPa.
Thermostat
Non-separable, with a solid temperature-sensitive element, with the main 4 (pic. eleven) and bypass valves 1 operating in the coolant temperature range of 87–102°C.
Pic. 11. Thermostat: 1 - bypass valve; 2 - outlet pipe (to the pump); 3 - main valve spring; 4 - main valve; 5 - branch pipe (from expansion tank); 6 - piston; 7 - inlet pipe (from the radiator); 8 - rubber insert; 9 - solid thermosensitive filler; 10 - bypass valve spring: 11 - inlet pipe (from the engine).
The thermostat is interchangeable with the VAZ-2108 engine thermostat.