Freeze Protection, Checking: Notes
Warning information for the high voltage system:
Procedures for which the ignition needs to be switched off. Refer to PROCEDURES FOR WHICH THE IGNITION NEEDS TO BE SWITCHED OFF .
Special tools and workshop equipment required
- Refractometer T10007 A
Coolant reservoir is under pressure. Open only when the engine is cold.
Freeze protection must be guaranteed down to approximately -25 °C (-13°F)), and in cold climate countries down to approximately -36°C (-33°F).
The amount of coolant additive must not exceed 55 % (freeze protection to -55°F (-48 °C), otherwise the freeze protection will decrease and the cooling effect will worsen.
The coolant system should remain filled with freeze protection the entire year. A proper mixture ratio of coolant additive will prevent a build-up of calcium, freezing and corrosion damage and will raise the boiling point.
In countries with tropical climates or when vehicle is driven under heavy load, the coolant improves the engine reliability by its increased boiling point.
Refractometer T10007 A must be used to determine the actual freeze protection.
Perform the following:
-- Use the pipette to apply a drop of coolant to the refractometer glass.
A light-dark line is clearly visible on the "WATERLINE" scale.
-- Use the corresponding Refractometer T10007 A scale to determine the coolant freeze protection. To do this, read the value on the light-dark line.
The refractometer scale -1- is designed for coolant additives G11, G12, G12+ and G12++.
The scale -2- is designed only for coolant additive G13.
If it cannot be guaranteed that the coolant additive will be filled unmixed: always use the G13 scale to determine the freeze protection.
The temperature on the Refractometer T10007 A corresponds to the >>crystalization point<<. At this temperature, the first flakes of ice begin to form.
-- Modify the composition of the coolant, if necessary, refer to IF THE FREEZE PROTECTION IS INSUFFICIENT: .
-- Check the freeze protection after the road test.