Refueling
The cooling system is filled with a coolant solution and coolant additives for the entire year. Other additives can significantly reduce the anti-corrosion effect. The resulting damage can lead to coolant leakage and, as a result, to serious engine damage. Coolants with the correct ratio of mixture components prevent the formation of corrosion and limescale. In addition, they increase the boiling point. Therefore, a concentrate must be present in the cooling system throughout the year. Especially in countries with a tropical climate, with high engine loads, a coolant with a high boiling point reliably protects the engine during operation. The freezing point of the coolant must be at least -25°C (in countries with an arctic climate, "at least" 35°C). It is also prohibited to reduce the proportion of concentrate in the coolant in the warm season or when operating in countries with a warm climate by adding water to the cooling system. The proportion of concentrate must be at least 40%. If it is necessary to reduce the freezing point of the coolant due to climatic conditions, the additive content can be increased, but not more than to 60% (the freezing point in this case will be about -40°C). If this limit is exceeded, the freezing point of the coolant will increase again, and, in addition, the efficiency of the cooling system will decrease. Use only clean drinking water to mix the coolant. When replacing the radiator, heater heat exchanger, cylinder head, cylinder head gasket or cylinder block, reusing the drained coolant is prohibited. Contaminated coolant cannot be used further. To check the concentrate in the cooling system, use the T10007 refractometer. The ratio of components in the coolant: Additive (40%) and coolant (60%) to ensure a freezing point of -25°C. Additive (50%) and coolant (50%) to ensure a freezing point of -35°C. Additive (60%) and coolant (40%) to ensure freezing temperature of -40°C. Close the drain plug. Pour 8 liters of coolant, pre-mixed with the additive in the correct proportion, into the coolant reservoir: Screw on the adapter of the cooling system tester "V.A.G 1274/8" to the expansion tank. Install the device for filling the cooling system on the adapter "V.A.G 1274/8". Place the outlet hose "1" in a small container "2". The air being discharged will capture a small amount of coolant, which must be collected.
Close valves "A" and "B" by turning them perpendicular to the flow direction. Connect hose "3" to the compressed air line. Excess pressure: 6...10 bar. Open valve "B" by turning it in the direction of the flow. A vacuum is created in the cooling system using an ejector pump; the indicator arrow should be in the green field. Open tap "A" briefly, for which turn it parallel to the flow direction so that the hose of the tank of the device for filling the cooling system is filled with coolant. Close tap "A" again.
Open valve "B" for 2 minutes. The ejector pump continues to create a vacuum in the cooling system; the indicator arrow should be in the green field. Close valve "B". The indicator arrow should remain in the green field, in which case the vacuum in the cooling system is sufficient for its subsequent filling. If the arrow is below the green field, then the previous operations should be repeated. If the vacuum decreases, check the cooling system for leaks. Remove the compressed air hose. Open valve "A". Due to the vacuum, the coolant coming out of the tank of the device for filling the cooling system fills the system. Remove the device for filling the cooling system from the adapter "V.A.G 1274/8" on the expansion tank. Put the tube on "V.A.G 1274/10" on the adapter "V.A.G 1274/8".
Remove seal "3". Release fastening clamps "1" from fasteners and remove water drainage box cover "2".
Unscrew the coolant hose to the heater heat exchanger and pull it back so that the vent hole in the coolant hose "arrow" is not closed by the connecting nipple. Fill with coolant so that it begins to flow out of the vent hole in the coolant hose. Put the coolant hose on the connecting nipple and secure it.
On vehicles with independent heating, switch on the heater for approx. 30 seconds. Close the expansion tank cap. Start the engine. Set the temperature to "HI" in all zones. Switch off the compressor by pressing the |econ| button. The engine should run at 2000 rpm for 3 minutes. Let the engine idle until the 2 large coolant hoses on the radiator are hot. The engine should run at 2000 rpm for 1 minute. Switch off and let the engine cool down. Install the front noise insulation shield. Check the coolant level. When the engine is cold, the coolant temperature should be at the MAX mark. When the engine is warm, the coolant level should be above the MAX mark.
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