Procedures
Cooling System, Draining and Filling
Special tools, testers and auxiliary items required
• Adapter (V.A.G 1274/8)
• Cooling System Charge Unit (VAS 6096)
• Drip Tray for Workshop Crane (VAS 6208)
• Hose Clamp Pliers (VAS 6362)
• Refractometer (T10007)
Procedure
• Collect escaping coolant in a clean container for disposal or reuse.
CAUTION!
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.
Drain the coolant in the engine.
- Remove the front noise insulation - 2 -.
- Place Drip Tray for Workshop Crane (VAS 6208) under engine.
- Remove the drain plug - 2 - on the coolant thermostat housing and drain the coolant.
- Remove the coolant hose - 1 - and let the coolant drain.
Drain the coolant completely.
If the coolant will be drained completely, the following procedures must be performed:
- Remove the front vehicle underbody cover - 1 -.
- Place the Drip Tray for Workshop Crane (VAS 6208) under the radiator.
- Remove the coolant hose - arrow - from the radiator and let the coolant drain.
Filling
• Tightening specifications. Refer to => [ Coolant Pump and Coolant Thermostat Assembly Overview ] Coolant Pump and Coolant Thermostat Assembly Overview.
• Ignition switched off.
• The cooling system is filled all year round with a mixture of frost and corrosion protection additives and water.
• 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.
• Frost and corrosion protection additives prevent freezing and corrosion damage and scaling. They also raise the boiling point. For this reason the system must be filled all year round with frost and corrosion protection additives.
• 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 (in arctic climatic countries to about -35 °C).
• 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 increased freeze protection is needed because of the climate, the amount of G12+ can be increased, but only up to 60% to provide freeze protection to about -40 °C. Otherwise the freeze protection and cooling effectiveness will be reduced.
• Only use clean drinking water for mixing coolant.
• Do not use drained coolant in the following situations:
• If the radiator, oil cooler, heat exchanger, cylinder head, cylinder head seal or cylinder block were replaced.
• If the coolant is contaminated.
• Replace the drain plug O-ring on the coolant thermostat housing.
• Secure all hose connections with hose clamps appropriate for the model.
• Use the Refractometer (T10007) to determine the level of freeze protection in the coolant system.
- Install the drain plug - 2 - with a new O-ring on the coolant thermostat housing.
- Connect the coolant hose - 1 -.
- Connect the coolant hose on the bottom of the radiator - arrow -.
- Install the front noise insulation and the front vehicle underbody cover.
- Fill coolant reservoir with at least 25 liters of premixed coolant with the proper mixture ratio:
• Coolant freeze and corrosion protection additive (40%) and water (60%) for freeze protection down to -25 °C
• Coolant freeze and corrosion protection additive (50%) and water (50%) for freeze protection down to -35 °C
• Coolant freeze and corrosion protection additive (60%) and water (40%) for freeze protection down to -40 °C
• Coolant freeze and corrosion protection additive.
- Attach Adapter (V.A.G 1274/8) to coolant reservoir.
- Install Cooling System Charge Unit (VAS 6096) on Adapter (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.
• Pressure: 6 to 10 bar 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 Cooling System Charge Unit (VAS 6096) 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 display must remain in green region, then vacuum in cooling system is sufficient for subsequent 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 Cooling System Charge Unit (VAS 6096) coolant reservoir by pressure in the coolant system and the system is filled.
- Remove Cooling System Charge Unit (VAS 6096) form Adapter (V.A.G 1274/8) on coolant reservoir.
- Loosen quick release couplings - 1 - and - 3 -.
- Press the bumper trim - 2 - toward the luggage compartment tray - arrow A -. This frees up the retaining tabs - arrows -.
- Then remove the bumper cover from the luggage compartment tray retaining groove - arrow -.
- Open the bleeder screw - arrow - until coolant comes out at the bleeder hole.
- Close the bleeder screw.
- Fill the coolant.
CAUTION!
The vehicle could overheat if the cap is installed incorrectly.
• The cap must engage noticeably when sealing.
- Tighten the cap on the coolant reservoir.
- Start engine.
- Adjust for full heat by turning the temperature selector to the " Warm" position.
- Switch the A/C compressor off by pressing the AC button.
• The LED in the button must not come on.
- Run engine at 2000 RPM for 3 minutes.
- Let the engine run at idle until both large coolant hoses to the coolant pipes in the center of the vehicle are warm.
- Run engine at 2000 RPM for 1 minute.
- Turn off engine and allow it to cool off.
- Check coolant level.
• Coolant level must be at "MAX" marking with engine cold.
• Coolant level may be above "MAX" marking with engine at operating temperature.