Cooling system, draining and filling: Filling

NOTE:

Use only coolant additive G 12 - meeting specification VW 774 D. Identification: colored red.
G 12 must not be mixed with any other coolant additives.
If the fluid in the expansion tank is brown, this is an indication that G 12 has been mixed with another type of coolant. In this case the coolant must be changed.
G 12 and coolant additives comply with specification VW 774D prevent frost and corrosion damage, scaling and also raise the boiling point of the coolant. For this reason the system must be filled all year round with the core additive for frost and corrosion protection.
Particularly in countries with tropical climates, the higher boiling point of the coolant improves engine reliability when working under heavy load.
The system must be protected against frost to about -35° C).
Use special tool T10007 to test coolant antifreeze protection.

Fig 1: Identifying Special Service Tool T10007
Courtesy of AUDI OF AMERICA, INC.
The coolant concentration should not be reduced by adding plain water, even in warmer seasons and in warmer countries. The concentration must be at least 40%.
If extra antifreeze protection is required in cold climates, the concentration of G 12 can be increased, but only up to a maximum of 60% (frost protection to about -40° C); if this concentration is exceeded, the antifreeze protection will be reduced again and cooling effectiveness will also be reduced.
Do not reuse the old coolant if the radiator, heat e changer, cylinder head or cylinder head gasket have been replaced.

Recommended mixture ratios:

COOLANT MIXTURE RATIOS SPECIFICATIONS

Frost protection to

Antifreeze concentration

G 12⁽¹⁾

Water⁽¹⁾

-25°C

40%

2.5 ltr.

3.5 ltr.

-35°C

50%

3.0ltr.

3.0 ltr.

⁽¹⁾	The capacity of the cooling system can vary depending on the equipment installed to the vehicle.

Replace O-ring on coolant drain screw and screw drain screw back into engine
Tightening torque: 20 Nm.
Install bottom coolant hose and secure.
Close coolant drain tap on radiator.
Screw adapter VAG 1274/8 onto expansion tank and insert extension VAG 1274/10 into the adapter.

Fig 2: Installing Extension To Adapter
Courtesy of AUDI OF AMERICA, INC.
Loosen coolant hose on heat exchanger and pull back hose far enough so that bleeder hole in hose -arrow- is no longer covered by the connection.

Fig 3: Locating Coolant Hose On Heat Exchanger (Heater Core)
Courtesy of AUDI OF AMERICA, INC.
Fill up coolant until it comes out at bleeder hole in coolant hose.
Push coolant hose onto connection and tighten.
Loosen bleeder screw on rear coolant line -arrow- below expansion tank.

Fig 4: Locating Bleeder Screw On Rear Coolant Line Below Expansion Tank
Courtesy of AUDI OF AMERICA, INC.
Fill up coolant until it comes out at bleeder screw.
Screw in bleeder screw (20 Nm).
Loosen bleeder screw on front coolant line -arrow- between power steering pump and left cylinder head.

Fig 5: Locating Bleeder Screw On Front Coolant Line
Courtesy of AUDI OF AMERICA, INC.
Fill up coolant until it comes out at bleeder screw.
Screw in bleeder screw (20 Nm).
Fill coolant up to max. mark.
Close filler cap on expansion tank.
Set heater controls to maximum heat setting.
Start engine and let it idle for about 10 minutes.
Maintain an engine speed of about 2000 RPM for about 5 minutes.
Allow engine to run at idling speed until bottom hose on radiator becomes hot.
Check coolant level and top off if necessary. When engine is at normal operating temperature coolant level must be on max. mark, and between min. and max. marks when engine is cold.

NOTE: When the engine is hot the cooling system is under pressure. Carefully open filler cap on expansion tank to release pressure before starting repair work.

WARNING: Hot steam can escape from the expansion tank when the filler cap is opened. Cover the filler cap with a cloth and remove it carefully.