To avoid malfunctions, it is recommended to check the concentration of antifreeze in the coolant before the onset of the winter period of vehicle operation. This is especially important if distilled water was added to replenish the coolant volume.
5. Warm up the engine until the upper radiator hose is slightly warm.
6. Remove the cover of the expansion tank.
7. Take the coolant from the expansion tank with a hydrometer and determine its density by the position of the hydrometer float (see illustration). In our climatic conditions, the coolant should not freeze at air temperatures down to -25°C, and in extreme cases - at -45°C.
8.7 Take the coolant from the expansion tank with a hydrometer
Increasing the density of the coolant
Attention! The radiator and heater are made of aluminium. For this reason, only antifreeze suitable for use on such units should be poured into the system.
Example: When measuring the density of the coolant in a car with a 1.6 liter petrol engine, it was found that the filled coolant provides frost protection only at an air temperature of -10°C. To ensure frost protection down to -35°C, drain 2.2 liters of coolant from the system and fill the system with 2.2 liters of pure antifreeze.
The calculations in the table below are based on a coolant temperature of +20°C.
8. Close the expansion tank cap and check the coolant level after a test drive.