1. The correct filling of the cooling system is checked by the level of liquid in the expansion tank, which, on a cold engine (at 15–20°C) should be 3-4 cm above the mark «MIN», printed on the expansion tank.
2. If necessary, check the density of the coolant with a hydrometer, which should be 1.078–1.085 g/cm3 for liquid Tosol A-40.
3. If the liquid level in the tank is below normal, and the density is above normal, then add distilled water. If the density is normal, add fluid of the same brand as the one in the cooling system.
4. If the density of the liquid in the cooling system is below normal, add Tosol-A liquid.