Cooling system of a four-cylinder engine
- 1 - Automatic transmission oil cooling heat exchanger;
- 2 - clamp;
- 3 - radiator supply hose;
- 4 - cover sealing ring
- thermostat;
- 5 - thermostat cover;
- 6 - thermostat;
- 7 - water pump housing;
- 8 - gasket;
- 9 - water pump cover;
- 10 - water pump roller;
- 11 - water pump pulley;
- 12 - fan casing;
- 13 - radiator casing;
- 14 - bracket;
- 15 - rubber bushing;
- 16 - fan switch sensor;
- 17 - sensor sealing ring;
- 18 - Electric fan;
- 19 - radiator outlet hose;
- 20 - radiator;
- 21 - Upper rubber bushing;
- 22 - Upper radiator shroud;
- 23 - steam outlet hose;
- 24 - expansion tank cap;
- 25 - expansion tank;
- 26 - hose from the tank to the radiator;
- 27 - water pump sealing ring;
- 28 - Automatic damper thermal switch;
- 29 - cooling jacket branch pipe;
- 30 - coolant temperature sensor;
- 31 - fan switch sensor;
- 32 - gasket;
- 33 - heater fluid intake pipe;
- 34 - heater fluid drain pipe;
- 35 - heat exchanger outlet hose;
- 36 - heat exchanger supply hose
Cooling system of a five-cylinder engine
- 1 - fan casing;
- 2 - electric fan;
- 3 - expansion tank;
- 4 - tank cap;
- 5 - clamp;
- 6 - hose from the tank to the radiator;
- 7 - radiator;
- 8 - lower radiator casing;
- 9 - Upper radiator shroud;
- 10 - steam outlet hose;
- 11 - water pump;
- 12 - sealing ring;
- 13 - radiator outlet hose;
- 14 - branch pipe;
- 15 - gasket;
- 16 - thermostat cover;
- 17 - thermostat;
- 18 - thermostat sealing ring;
- 19 - Electric fan switch sensor;
- 20 - thermostat supply hose;
- 21 - pipe for supplying liquid to the heater;
- 22 - heater supply hose;
- 23 - heater outlet hose
The cooling system is completely sealed and consists of a radiator, water pump, thermostat, expansion tank, connecting hoses, and an electric fan. The radiator is installed in front of the engine on cars with four-cylinder engines or on the side. with five-cylinder engines. The system works as follows. While the engine is cold, the thermostat is closed and the liquid circulates in a small circle, bypassing the radiator. When the liquid temperature reaches approximately 87°C, the thermostat begins to open, and the liquid. circulates in a large circle through the radiator. The electric fan is controlled by a fan switch located at the bottom of the radiator. The fan turns on when the coolant temperature is 93–98°C, and turns off at 88–93°C.
Cooling system capacity (with heater) is:
| Four-cylinder engines |
7.0 l
|
| Five-cylinder petrol engines, except MS |
8.1 l
|
| MS engines |
8.5 l
|
| Naturally aspirated diesels |
8.0 l
|
| Turbocharged diesels |
9.4 l
|
It is recommended to change the coolant approximately every 2 years, as well as when replacing the radiator, engine, cylinder head, etc.
(Content source: the specified website: «AUDImanual»)