Audi 80/Avant (B4)

Since 1991-1995 of release

Repair and car operation



Audi 80/Avant
+ The description
+ Engines
+ System of release of the fulfilled gases
- Cooling system
   Check of level of a cooling liquid
   Frost resistance check
   Check of system of cooling on tightness
   Radiator
   Carving cover of a broad tank
   The thermostat
   The list of malfunctions
   The water pump
   Klinovoj belt of the water pump
   The fan of system of cooling
   Malfunctions of the fan of system of cooling
   The list of malfunctions
+ Fuel tank and the fuel pump
+ The air filter and воздухозаборные channels
+ Injection system
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Antiblocking system of brakes
+ Wheels and tyres
+ Kuzovnaja electrosystem
+ Ignition system
+ Illumination
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ Body elements
+ Search of malfunctions
+ Specifications



The list of malfunctions

The thermostat

Malfunction sign
The reason/consequence
A.Indikator of temperature rises slowly, the working temperature is reached later, insufficient heating effect The plate of the valve of the thermostat is blocked in position "openly" («offen»), for example because of adjournment; the stream to a radiator remains constantly opened. The engine too long remains in a mode of operation of cold start. During short time there should be, however, no damages. Despite it, it is necessary to replace the thermostat as soon as possible.
V.Strelka of the temperature indicator has completely deviated to the right, despite correct level of a liquid, the indicator of a cooling liquid blinks. The radiator and the bottom tube to a radiator remain cold. The plate of the valve of the thermostat is blocked in position "is closed" («zu») (for example because of a faulty or not tight sleeve of the thermostat). It is not necessary to continue in no event movement, otherwise the engine can receive the most serious damages because of an overheat! Immediately to replace the thermostat.  

 The help: if the engine begins to boil on road because of the faulty thermostat can help or эвакуатор, or thermostat removal on a place. If you have dared to remove the thermostat it is necessary to wait until the temperature of cooling means will not go down. At this time you can get capacities for plum of a cooling liquid.

Thermostat removal

At the 6-cylinder engine the case of the thermostat (marksman) is located to the right of the block of cylinders.

Removal of the jammed thermostat on the journey – problematic enough employment. It is located deeply enough below so it is necessary to merge almost all охладающую a liquid. Besides at the hot engine it is necessary to wait long before it is possible to start to work, without being afraid to scald itself a hand. At installation of the new thermostat it is necessary to replace also a sealing lining on the case of the thermostat or the water pump.

 PERFORMANCE ORDER

  1. Completely to merge cooling liquid.
  2. Models with 4-cylinder engines: to remove the bottom protection of a motor compartment (the head body Elements).
  3. To remove a hose below on the case of the water pump (it has already been made for plum of a cooling liquid).
  4. To turn off two bolts on a cover in the bottom part of the case of the thermostat.
  5. To uncover and the thermostat.
  6. Models with 5-cylinder engines: to turn off two bolts on a cover of the case of the thermostat.
  7. To press on a cover aside and to remove the thermostat.
  8. Models with 6-cylinder engines: to remove клиновой a belt, to take out the tension device (Generator).
  9. To remove a protective casing of a gear belt (the head Engines). The gear belt remains established.
  10. To remove a hose of system of cooling, the leader to a radiator and located below on a branch pipe of the case of the thermostat.
  11. To turn off two bolts on a cover of the case of the thermostat.
  12. Cautiously to lift a gear belt through a partition on the thermostat case, to remove the thermostat case.
  13. To take out the thermostat.
  14. All models: at installation of the new thermostat its smaller condensing plate should show towards the engine.
  15. Only models with the 6-cylinder engine: the air valve on an external ring of the thermostat should show upwards.
  16. To replace a lining.
  17. To tighten bolts on the case of the thermostat or the water pump the moment 10 Н•м.

Thermostat check

With the thermometer for jam making you can define, whether the regulator of a cooling liquid opens at the ordered temperature.

 The opening beginning
Opening end
Lifting height
Approximately 87°С
Approximately 102°С
7—8 mm

 PERFORMANCE ORDER

  1. To remove the thermostat.
  2. To hang up the thermostat in a pan with water and to warm up water.
  3. To check, whether the valve plate rises at 87°С from a saddle.
  4. Opening end at this experience cannot be reached completely (in an open pan water boils, as it is known, at 100°С), but at least it is possible to see, whether the thermostat opens further.
  5. The full height of lifting is almost reached by that. That it is possible to see, the conclusion is enough to draw on serviceability or malfunction of the thermostat.