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Cooling System, Checking Freeze Protection And Coolant Level: Notes

NOTE:

The water used for mixing greatly influences the effectiveness of the coolant. Do to the different water contents which can vary due to country or region, the water quality used is defined. Distilled water fulfills all the requirements. For this reason mix coolant with distilled water when supplementing and refilling the cooling system.

Use only coolant additives according to the parts information. Using other coolant additives can impair the corrosion protection. Loss of coolant can cause considerable damage to the engine.

Coolant in the correct mixing ratio prevents freezing and corrosion damage as well as scaling. The boiling temperature is also increased. For these reasons the cooling system must have coolant additive the whole year.

Especially in countries with tropical climates or when vehicle is driven under heavy engine load, the coolant improves the engine reliability by its increased boiling point.

The Refractometer :T10007A  MUST be used to determine the actual freeze protection value.

GWWN01-11006Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

The freeze protection must be set to minimum -25 °C (-13 °F), for countries with an arctic climate, it must be set to approximately -36 °C (-32.8 °F). The freeze protection can be increased only when a stronger freeze protection is required due to climatic conditions. But only down to -48 °C (-54 °F), otherwise the cooling effect of the coolant will be impaired.

The coolant concentration must not be reduced by adding water, even during the warmer season or in warm countries. The freeze protection must be a minimum of -25 °C (-13 °F).

Read off the freeze protection value on the scale for each respective refilled coolant additive.

The temperature on the Refractometer :T10007A  corresponds to the >>crystallization point<<. At this temperature, the first flakes of ice begin to form in the coolant.

Do not reuse used coolant.

Only use water/coolant additive as lubricant for the coolant hoses.