Cooling System, Draining and Filling
Cooling system, draining and filling
Special tools and equipment required
^ Adapter for cooling system tester V.A.G. 1274/8
^ Drip tray V.A.G. 1306
^ Hose clamp pliers V.A.G. 1921
^ Cooling system charge unit VAS 6096 with VAS 6096/1
^ Refractometer T10007
Draining
Note:
Collect drained coolant in a clean container for re-use or disposal.
CAUTION
Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
- Open filler cap on expansion tank.
- Remove fasteners -1... 3- and remove center sound insulation.
- Place drip tray V.A.G. 1306 under engine.
- Turn drain plug (arrow) on radiator counter-clockwise and, if necessary, fit a drain hose to connection.
- In addition, remove lower coolant hose at After-run coolant pump -V51- (arrow) and drain remaining coolant.
Filling
Note:
^ The cooling system must be filled year round with a mixture of water and frost and corrosion protection additives.
^ Only use coolant additive Plus G 012 A8F A1 (also designated as "G12+") meeting specification TL VW 774 F. Other coolant additives could seriously impair in particular the anticorrosion properties. The resulting damage could lead to loss of coolant and consequently to serious engine damage.
^ Coolant additive "G12+" may be mixed with additives "G11" and "G12".
^ "G12+" and coolant additives marked with "Meets specification TL VW 774 F" prevent frost and corrosion damage as well as stop scale from forming. They also raise the boiling point. Therefore, cooling system must be filled year round with the correct antifreeze and corrosion protection additives.
^ A higher boiling point improves engine reliability under heavy load particularly in countries with tropical climates.
^ Frost protection must be ensured to about -25 degrees C (about -35 degrees C in countries with arctic climates).
^ The coolant concentration must not be reduced by adding water even in warmer seasons and in warmer countries. The coolant additive portion must be at least 40%.
^ If greater frost protection is required in very cold climates, the amount of "G12+" can be increased, but only up to 60% (this gives frost protection to about -40 degrees C). If the antifreeze percentage exceeds 60%, frost protection decreases again and cooling efficiency is also impaired.
^ Only use clean drinking water for mixing coolant.
^ If the radiator, heat exchanger, cylinder head, cylinder head gasket or cylinder block have been replaced, do not re-use the old coolant.
^ Contaminated or dirty coolant must not be used again.
^ To check frost protection level of coolant additive "G12+" use refractometer T10007.
- Close drain plug (arrow).
- Connect coolant hose to After-run coolant pump -V51- (arrow).
- Fill reservoir VAS 6096/1 with at least 8 liters of premixed coolant (based on recommended ratio):
^ "G12+" (40%) and water (60%) for frost protection to 25 degrees C
^ "G12+" (50%) and water (50%) for frost protection to 35 degrees C
^ "G12+" (60%) and water (40%) for frost protection to 40 degrees C
- Screw adapter for cooling system tester V.A.G. 1274/8 onto coolant expansion tank.
- Mount cooling system charge unit VAS 6096 onto adapter V.A.G. 1274/8.
- Feed vent hose -1- into a small container -2-. (The vented air draws along a small amount of coolant, which should be collected.)
- Close both valves -A- and -B- (turn lever perpendicular to direction of flow).
- Connect hose -3- to compressed air.
^ Pressure: 6... 10 bar
- Open valve -B- (turn lever in direction of flow).
The suction jet pump generates a vacuum in the cooling system.
^ Needle on gauge must move into green zone
- Also briefly open valve -A- (turn lever in direction of flow) so that hose on coolant expansion tank, VAS 6096/1, can fill with coolant.
- Close valve -A- again.
- Leave valve -B- open for another 2 minutes.
^ Suction jet pump will continue generating a vacuum in the cooling system.
^ Needle on gauge must remain in green zone.
- Close valve -B-.
^ Needle on gauge must stop in green zone. Vacuum level in cooling system is then sufficient for subsequent filling.
If the needle does not reach the green area, repeat the process.
If the vacuum level drops, there is a leak in the cooling system.
- Disconnect compressed air hose.
- Open valve -A-.
The vacuum in the cooling system causes the coolant to be drawn out of the cooling system charge unit VAS 6096/1; the cooling system is then filled.
- Check coolant level and top up coolant as far as MAX mark.
- Start engine, run for maximum of 2 minutes at approx. 1500 RPM and fill coolant up to overflow hole on expansion tank.
- Close expansion tank.
- Run engine until coolant fan starts.
WARNING!
Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
- 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 coolant level must be between MIN and MAX marks.
- Switch engine off.