Cooling system: Check freeze protection, add coolant, if necessary

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NOTE:

All new engines are filled with coolant additive G 12 Plus according to TL VW 774 F (purple color). G 12 Plus can be mixed with the previous coolant additives G 11 and G 12 (red). Ensure that the system is replenished only with G12 Plus (due to its positive properties).
G 12 Plus is suitable as a filled-for-life filling for cast iron and all-aluminum engines and gives optimum protection against freezing, corrosion damage, scaling and over-heating.
G 12 Plus increases the boiling point to 2.5F (135C) and ensures for a better heat dissipation.
The coolant portion of the mixture must amount to at least 40% (freeze protection to -13F [-25C]) and should not exceed 60% (freeze protection to -40F [-40C]). Otherwise the freeze protection will be reduced and the cooling efficiency will be worsened.
The freeze protection must be ensured to approximately -13F (-25 C).

Checking freeze protection and adding coolant additive if necessary

Special tools, testers and auxiliary items required

Fig 1: Identifying Refractometer T10007

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Refractometer T10007

NOTE:

Read the bright/dark boundary to obtain an accurate reading for the following tests. Place a drop of water on the glass to improve the readability of the bright/dark boundary. The bright/dark boundary can be clearly recognized on the "WATERLINE".
Check the concentration of the coolant additive using refractometer T10007 (operating instructions).

Fig 2: Identifying Refractometer Scales

Courtesy of VOLKSWAGEN UNITED STATES, INC.

The scale - 1 - of the refractometer is designed for coolant additives G 12; G12 Plus and G11.

Scale - 2 - refers only to coolant additive G 13. (previously L80)

NOTE:

The freeze protection must be ensured to approximately -13F [-25C].
If for climatic reasons greater freeze protection is required, the amount of G 12 Plus can be increased, but only up to 60% (freeze protection to about -40F [-40C]), otherwise freeze protection and cooling effectiveness will be reduced.
If freeze protection is insufficient, drain off required quantity shown in freeze protection table and add coolant additive G 12 Plus.

NOTE:

Observe waste disposal regulations!
Check coolant additive concentration after test drive again.

Checking coolant level and adding coolant if necessary

Check coolant level in expansion tank with engine cold.

Fig 3: Checking Coolant Level

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Delivery inspection: Coolant level above the "MIN marking" - arrow -.
Inspection service: Coolant level above the "MIN marking" - arrow -.

If coolant is too low, add required amount according to mixture ratio.

NOTE:

Determine cause of fluid loss which cannot be attributed to normal use and rectify (repair measure).

Mixture ratio:

NOTE:

Coolant additive G 12 Plus conforming to TL VW 774 F prevents freeze and corrosion damage, scaling, and raises the boiling point. For these reasons, the cooling system must be filled with radiator freeze and corrosion protection fluid all year round.
Especially in countries with tropical climates or when vehicle is driven under heavy load, the coolant improves the engine reliability by its increased boiling point.
The coolant concentration must not be reduced by adding water, even during the warmer season. The coolant additive ratio must be at least 40%.