Testing Values and Process Specifications Table:
| Service: | Specified Coolant Level: |
|---|---|
| Delivery service | Coolant level must be at least up to the MAX mark. |
| Inspection | Coolant level at the MAX mark. |
A leak test for the coolant system is a repair procedure and should be charged separately.
Requirements:
- Freeze protection must be guaranteed down to -25 °C (-13 °F), and in cold climate countries down to -36 °C (-33 °F). Observe the target value specification in the maintenance table.
- The amount of coolant additive must not exceed 55 % (freeze protection value to -48 °C (-55 °F)), since the freeze protection will decrease and the cooling effect will worsen.
- The vehicle must be stopped and in a level position.
Step 1 - Coolant Level, Checking:
-- When the engine is cold, check the coolant level in the coolant expansion tank based on the container markings -image-.
-- If the coolant level is too low, fill the missing amount in the required mixture ratio. Refer to COOLANT, FILLING .
-- If there is a loss of fluid not due to normal use, first determine the cause with a leak test. Refer to COOLING SYSTEM, CHECKING FOR LEAKS - 2.0 or COOLING SYSTEM, CHECKING FOR LEAKS 2.9, 3.0 .
Step 2 - Freeze Protection, Checking:
-- Use the pipette to apply a drop of coolant to the glass on the Refractometer:T10007 A . The cut-off line can now be clearly recognized through to the refractometer.
-- Use the corresponding scale to determine the coolant freeze protection. Read the value on the cut-off line to do so.
-- If the freeze protection value does not match the specification in the Maintenance Table, perform the following actions:
| Freeze Protection Value: | Evaluation / Action: |
|---|---|
| Greater than the specified value guideline | Depending on the variance, remove a small amount of coolant and replace with distilled water. Repeat the procedure until the correct coolant mixture is obtained. |
| Less than the specified value guideline | Depending on the deviation, remove a small amount of coolant and replace with coolant additive. Repeat the procedure until the correct coolant mixture is obtained. |
-- Check the concentration of the coolant additive again after the road test.
The Refractometer:T10007A must be used to determine the actual freeze protection density.
The scale -1- on the refractometer refers to the G12++ and G12evo coolant additives.
The scale -2- only applies to coolant additive G13.
If more than one type of coolant additive has been used, use the scale for G13 to determine the frost protection.
The temperature on the Analog Refractometer:T10007B corresponds to the >>crystallization point<<. At this temperature, ice crystals may begin to form in the coolant.
The coolant system should always be filled with freeze protection the entire year. A proper mixture ratio of coolant additive will prevent the build-up of calcium, freezing and corrosion damage and will also raise the boiling temperature.
In countries with tropical climates, the coolant improves the engine reliability due to the increased boiling point when the vehicle is driven under heavy load.