Coolant: Service and Repair
Cooling System, Draining and Filling
Special tools, testers and auxiliary items required
• Adapter (V.A.G 1274/8)
• Drip Tray (VAS 6208)
• Hose Clip Pliers (V.A.G 1921)
• Cooling System Charge Unit (VAS 6096)
• Refractometer (T10007)
Draining
Risk of scalding due to hot steam and hot coolant.
• When the engine is warm the cooling system is under pressure.
• To reduce pressure, cover coolant reservoir cap with cloth and carefully open.
- Open coolant reservoir cap.
- Remove noise insulation.
Cabriolet
- Remove the noise insulation bracket.
All
- Remove the air guide pipe - 1 and 2 -.
• Drained coolant must be stored in a clean container for disposal or reuse.
- Place (VAS 6208) under engine.
- Remove the lower coolant hose - 1 - from the radiator and let the coolant drain.
• Ignore - 2 -.
- Remove lower coolant hose to after-run coolant pump (V51) - arrow - and allow coolant to drain.
Filling
• The cooling system is filled year year-round with a mixture of water and coolant additive. Mixture ratio.
• Only use one of the frost and corrosion additives approved for this vehicle. Other coolant additives may above all reduce the corrosion protection effect significantly. The damage resulting from this may lead to loss of coolant and consequently to severe engine damage.
• Coolant with the correct mixture ratio prevents freezing and corrosion damage and calcium deposits. They also raise the boiling point. The cooling system must be filled with coolant additive year-round.
• Because of its high boiling point, the coolant improves engine reliability under heavy loads, particularly in countries with tropical climates.
• Protection against frost must be assured to about -25 °C (-13 °F) (in arctic climatic countries to about -35 °C (-31 °F)).
• The coolant concentration must not be reduced by adding water even in warmer seasons and in warmer countries. Coolant additive portion must be at least 40%.
• If more freeze protection is needed due to the climate, increase the amount of coolant additive, but only up to 60% (freeze protection down to -40 °C (-40 °F)). Otherwise the freeze protection and cooling effectiveness will be reduced.
• Only use clean drinking water for mixing coolant.
• If radiator, heat exchanger, cylinder head or head seal or cylinder block were replaced, do not reuse used coolant.
• Dirty coolant may not be used again.
• Use the (T10007) to determine the level of freeze protection in the coolant system.
• Secure all hose connections with hose clamps appropriate for the model.
Coolant mixture ratio
• Coolant (40%) and water (60%) for freeze protection down to -25 °C (-13 °F)
• Coolant (50%) and water (50%) for freeze protection down to -35 °C (-31 °F)
• Coolant (60%) and water (40%) for freeze protection down to -40 °C (-40 °F)
• Coolant
- Connect the lower coolant hose - 1 - to the radiator.
- Connect coolant hose to after-run coolant pump (V51) - arrow -.
All:
- Fill the coolant reservoir on the (VAS 6096) with at least 10 liters of premixed coolant with the proper mixture ratio.
- Attach (V.A.G 1274/8) to coolant reservoir.
- Install (VAS 6096) on (V.A.G 1274/8).
- Place air outlet - 1 - in a small container - 2 -.
• A small amount of coolant which should be collected is drawn off with the discharged air.
- Close valves - A - and - B - by turning lever at a right angle to direction of flow.
- Connect hose - 3 - to compressed air.
• 6 to 10 bar positive pressure.
- Open valve - B - by turning level in direction of flow.
• The suction jet pump generates pressure in the coolant system; indicator on display instrument must move into green area.
- Briefly open valve - A - by turning lever in direction of flow so that hose on (VAS 6096) coolant reservoir fills with coolant.
- Close valve - A - again.
- Leave valve - B - open another 2 minutes.
• More pressure is generated in the coolant system by the suction jet pump; indicator on display instrument must stay in green area.
- Close valve - B -.
• Needle in the display instrument must remain in the green region, then the sufficient vacuum in the cooling system is obtained for the upcoming filling.
• If needle stands below the green area, repeat procedure.
• If pressure falls, check coolant system for leaks.
- Remove pressurized air hose.
- Open valve - A -.
• Coolant is extracted from the (VAS 6096) coolant reservoir by pressure in the coolant system and the system is filled.
- Check coolant level.
- Fill coolant up to "max" marking.
- Start engine and run at approximately 1500 RPM for a maximum of 2 minutes.
- With engine running, fill coolant up to overflow hole on coolant expansion tank.
- Close the cap on the coolant reservoir.
- Start the engine and let it run at approximately 3000 RPM until the coolant fan starts running.
Risk of scalding due to hot steam and hot coolant.
• When the engine is warm the cooling system is under pressure.
• To reduce pressure, cover coolant reservoir cap with cloth and carefully open.
- Check coolant level.
• With warm engine, coolant level must be at "max" marking, with cold engine, between "min" and "max" marking.
- If necessary, top off with coolant again.
- Shut off engine.