engine coolant AUDI TT 1995 8N / 1.G AEB ATW Engines Cooling System Components Workshop Manual
Page 1 of 34
19-1
 
     
Cooling system components, 
removing and installing 
     
WARNING! 
     
The cooling system is pressurized when the 
engine is warm. When opening the expansion 
tank, wear gloves and other appropriate 
protection, cover the cap using a cloth, and 
open carefully to relieve system pressure 
slowly. 
     
Note:  
     
Cooling system is under pressure when engine 
is warm. If necessary reduce pressure before 
repair. 
     Secure all hose connections using production-
type clamps   parts catalog. 
     
VAG1921 pliers are recommended for installing 
spring clips. 
     Always replace gaskets, seals and O-rings.
     Arrows on coolant lines and hoses must 
align. 
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Page 4 of 34
19-4
      
Cooling system, draining and filling
 
     
Special tools and equipment  
     
VAG1306 drip tray
     VAG1274/10 with VAG1274/1 adapter or 
VAG1274/8 
     T40007 refractometer
     
Draining  
     
Note:  
     Drain coolant into a clean container for recycling 
or reuse. 
     
WARNING! 
     
The cooling system is pressurized when the 
engine is warm. When opening the expansion 
tank, wear gloves and other appropriate 
protection, cover the cap using a cloth, and 
open carefully to relieve system pressure 
slowly. 
     
-  Open coolant expansion tank cap.
    
-  Remove noise insulation panel (arrows).
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Page 5 of 34
19-5
      
-  Place VAG1306 drip tray underneath engine.
     
CAUTION! 
     
Observe disposal regulations for coolant! 
    
Note:   -  Remove retaining clip (arrow) from lower coolant hose and remove 
coolant hose from radiator. 
    
With bumper removed, coolant can be drained through radiator drain plug 
(arrow). 
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Page 6 of 34
19-6
 
    
Filling  
Note: 
CAUTION!  -  Remove drain plug from coolant pump (arrow).
The cooling system is filled year-round with frost and corrosion 
protection additives. Until 6/96, G 011 A8 C coolant (green color) was used.From 7/96 on, only G 012 A8 D coolant (red color) is used.Coolants G 011 A8 C and G 012 A8 D CANNOT be mixed. Mixing 
them will cause severe engine damage. Part numbers are for reference only. Always check with your Parts 
department for the latest information. If the fluid in the expansion tank is brown, G012 A8 D has been mixed 
with other coolant. In this case, flush cooling system and change 
coolant. To flush, fill cooling system with clear water and run engine 
for approx. 2 minutes. Flushing the system should remove most of the 
coolant residue. 
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Page 7 of 34
19-7
      
Note (continued from page   Page 19
-6 ):  
     
G 011 A8 C or G 012 A8 D and coolant 
additives marked with "according to TL VW 
774C" or "according to TL VW 774 D", prevent 
frost and corrosion damage as well as calcium 
deposits. They also raise the boiling point. 
Therefore, cooling system must be filled year-
round with frost and corrosion protection 
additives. 
     A higher boiling point improves engine reliability 
under heavy load, particularly in countries with 
tropical climates. 
     Frost protection additives must protect against 
frost to about -25 C (-13 F) and to about -35
C (-31 F) in arctic climates. 
     
The coolant concentration must not be reduced 
by adding water even in warmer seasons and in 
warmer countries. The anti-freeze ratio must be 
at least 40%. 
     If for climatic reasons greater frost protection is 
required, the amount of G 011 A8 C or G 012 
A8 D can be increased, but only up to 60% to 
obtain frost protection to about -40 C (-40 F). 
Otherwise frost protection and cooling 
effectiveness will be reduced. 
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Page 8 of 34
     
If the radiator, heater core, cylinder head or 
cylinder head gasket is replaced, completely 
replace the engine coolant. 
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Page 11 of 34
19-10
      
-  Start engine and maintain an engine speed of 
about 2000 RPM for approx. 3 minutes. 
     
-  Allow engine to idle until the lower radiator hose 
is hot.Check coolant level and top up if 
necessary. When engine is at normal operating 
temperature, coolant level must be at max. 
mark; when engine is cold, between min. and 
max. marks. 
     
WARNING! 
     
The cooling system is pressurized when the 
engine is warm. When opening the expansion 
tank, wear gloves and other appropriate 
protection, cover the cap using a cloth, and 
open carefully to relieve system pressure 
slowly. 
     
-  Switch engine off.
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Page 14 of 34
19-13
      
Coolant pump, removing and installing
 
     
Note:  
     Coolant pump is bolted to bracket for generator, 
power steering pump and viscous fan. 
     
Lock carrier in service position   Page 13
-1 
     
Removing  
     
CAUTION! 
     
Before disconnecting the battery: 
     
Stop the engine.
     Determine the correct coding for the anti-
theft radio. 
     Switch the ignition off (also applies when 
connecting the battery). Failure to do so may 
damage the Engine Control Module (ECM). 
    
-  Switch ignition off and disconnect battery Ground (GND) strap.
-  Remove ribbed belt   Page 13
-15
 .
-  Remove viscous fan (with belt pulley)   Page 13
-14
 , Fig.   1
 .
- Remove V-belt   Page 13
-18
 .
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Page 19 of 34
19-17
      
Note:  
     When installing ribbed belt, check for correct 
seating on belt pulley. 
     
- Install V-belt   Page 13
-18
 .
     
-  Fill up with coolant   Page 19
-6 .
     
WARNING! 
     
The cooling system is pressurized when the 
engine is warm. When opening the expansion 
tank, wear gloves and other appropriate 
protection, cover the cap using a cloth, and 
open carefully to relieve system pressure 
slowly. 
     
CAUTION! 
     
Be sure the ignition is switched OFF. Failure 
to do so may damage the Engine Control 
Module (ECM). 
     
-  Switch ignition off and reconnect battery Ground 
(GND) strap. 
     
-  After connecting battery, enter anti-theft code for 
radio. 
     
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Page 24 of 34
19-20
      
Coolant thermostat, removing, installing 
and checking
 
     
Removing  
     
- Drain coolant   Page 19
-4 .
    
Installing  
WARNING! 
The cooling system is pressurized when the engine is warm. When 
opening the expansion tank, wear gloves and other appropriate 
protection, cover the cap using a cloth, and open carefully to relieve 
system pressure slowly. 
Tightening torque   -  Remove bolts -4-, remove connector -3-, O-ring -2- and coolant 
thermostat -1-. 
-  Clean and/or smooth O-ring sealing surface.
-  Install coolant thermostat. 
-  Fill up with coolant   Page 19
-6 .
Component  
Tightening torque  
Connector to pump housing   10 Nm (7 ft lb)  
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