The coolant level must be checked before every long distance trip.
For refilling, it is necessary to use a low-temperature concentrate G12 A8D or a concentrate with specification TL-VW 774 D (pay attention to the inscription on the container) and clean water with a low lime content.
Safety instructions
When opening the expansion tank cap on a hot engine, care must be taken, as escaping vapors can cause severe burns. To do this, close the cap of the expansion tank with a thick layer of cloth and slowly unscrew the cap until a hissing sound is heard. After the hiss stops, slowly unscrew and remove the cap from the expansion tank. Remove the cap from the expansion tank only at temperatures below +90°C.
Coolant level on a cold engine (coolant temperature approx. 20°C) must be between the MIN and MAX marks on the expansion tank (see fig. 1.10). On a hot engine, the coolant level should be near the MAX mark.
Large amounts of cold coolant should only be topped up when the engine is cold to prevent damage to the engine.
Unscrew the cap of the expansion tank, for which first relieve the residual pressure in the cooling system, then completely unscrew the cap.
If the coolant level drops significantly in a short period of time, determine and repair the cause of the fluid leak.
Coolant Density Check
Before the winter season, check the density of the low temperature concentrate, especially if distilled water was added to the cooling system during the warm season.
To check the density, a HAZET 4810 hydrometer or equivalent must be used.
Warm up the engine briefly until the upper radiator hose is slightly warm. When measuring density, the coolant temperature must be 20°C.
Unscrew the cap of the expansion tank, for which first relieve the residual pressure in the cooling system, then completely unscrew the cap.
Type the coolant into the hydrometer and use the scale on the float to determine its density (see fig. 1.11).
According to the table, determine the freezing point of the coolant depending on its density. The freezing point should be between -25°C and -35°C.
Adding coolant
If G12 A8D low temperature concentrate is temporarily unavailable, no other concentrate should be added to the system. In this case, only distilled water can be added; at the first opportunity, it is necessary to restore the required composition of the coolant by adding the recommended low-temperature concentrate.
With frost protection down to -25°C, the proportion of concentrate in the coolant should be 40%. To protect against frost down to -35°C, water and concentrate must be mixed in a ratio of 1:1.
Attention. The proportion of antifreeze should not exceed 60% (which corresponds to protection up to -40°С), as otherwise the protective and cooling properties of the coolant will decrease.
It is not recommended to use the previously used mixture of antifreeze and anti-corrosion agent G11, which is green. Do not mix anti-corrosion agent G11 and G12 A8D (Red), as this can cause severe engine damage.
Instruction. If coolant not recommended by the manufacturer was poured into the cooling system, drain it from the cooling system. Fill the cooling system with clean water and run the engine at idle speed for 2 minutes. Drain the water from the cooling system and blow out the engine cooling system with compressed air through the expansion tank. Fill with fresh coolant recommended by the manufacturer.
The table indicates how much G12 A8D low temperature concentrate must be topped up to obtain the required concentration (density) coolant. The table shows only control figures, since the volumes of coolant differ for each specific engine.
Example. Density measurement showed that the freezing point of the coolant is -10°C for a 4-cylinder gasoline engine. In this case, 2 liters of coolant must be removed from the cooling system and 2 liters of pure concentrate G12 A8D should be added instead. In this case, the freezing point of the coolant will be -25°C.
Install the cap on the expansion tank. Take a test drive and re-measure the density of the coolant.
Visitor comments