VW Passat repair


+ 1. Ekspluatatsiiya of the car
+ 2. Maintenance
+ 3. Engines
- 4. Cooling system
   4.1. General information
   4.2. Check of tightness of hoses of system of cooling
   4.3. Check of level of cooling liquid
   4.4. Replacement of cooling liquid
   4.5. Washing of system of cooling
   4.6. General control of system of cooling
   - 4.7. Removal and installation of elements of system of cooling
      4.7.1. Radiator
      4.7.2. Thermostat
      4.7.3. Pump of system of cooling
      4.7.4. Fan of system of cooling
      4.7.5. Sensor of turning on of the electrofan
      4.7.6. The sensor of temperature of cooling liquid
      4.7.7. Thermorelay of system of injection of fuel
      4.7.8. Replacement of technological caps
      4.7.9. Heater
      4.7.10. Control unit heater
+ 5. Power supply system
+ 6. Ignition system
+ 7. Coupling
+ 8. Transmission
+ 9. Drive of forward wheels
+ 10. Suspension brackets
+ 11. Steering
+ 12. Brake system
+ 13. Wheels and tires
+ 14. Systems of heating, ventilation and conditioning
+ 15. Electric equipment
+ 16. Body
+ 17. Electric circuits


Repair B3-B4/Passat B3-B4 Volkswagen Passat>> Cooling system>> Removal and installation of elements of system of cooling>> Thermostat
Removal of the thermostat carry out in the following order:

Fig. 4.1. System of cooling of the SOHC engine: 1–radiator; 2–thermostat; 3–connecting branch pipe; 4–broad tank; 5–top cover;    6–air inlet; 7–fan (EZ) arm; 8–fan arm (RV, RP); 9–arm of fans; 10-additional fan; 11-driving belt; 12-electric fan


Fig. 4.2. System of cooling of the DOHC engine: 1–radiator; 2–pump; 3–thermostat; 4–broad tank; 5–oil heat exchanger; 6–back cover; 7–fan arm; 8–arm of fans; 9–electric fan; 10-additional fan; 11-driving belt; 12-top cover; 13-air inlet


– the thermostat 2 (see  fig. 4.1 ) and 3 (see  fig. 4.2 ) is located in the basis of the case of the water pump;
– merge cooling liquid from cooling system;
– unscrew two bolts of fastening and uncover the thermostat;
– remove a sealing ring;
– get the thermostat from the case in the basis of the water pump.

       PREVENTION
Before removal of the thermostat note its situation in the case.

Check of the thermostat carry out in the following order:

Fig. 4.5. Working positions of the thermostat: a–the thermostat is closed; – the thermostat is open


– if the thermostat is in open situation (fig. 4.5) at room temperature, it is subject to replacement;

Fig. 4.6. Thermostat check


– for check of the thermostat lower it on a twine in the container with water (fig. 4.6) . Gradually heating up water, measure temperature at which the thermostat starts to open and completely will open. Take the thermostat from water and check, that it was completely closed after cooling. Replace the thermostat if its parameters differ from technical requirements.
Installation of the thermostat carry out in the following order:
– clear the case of the thermostat and interfaced surfaces;
– establish the thermostat in the case in situation in which the thermostat was before removal;
– establish a new sealing ring of round section;
– establish a cover and tighten bolts of fastening the demanded moment;
– establish hoses of system of cooling, an arm of the pump of the amplifier of a steering;
– establish a driving belt of the pump;
– fill system of cooling with liquid.