Warning! Wait until the engine has cooled down before starting the procedure. Do not allow antifreeze to come into contact with skin or painted parts of the car body. Immediately wash off any spilled antifreeze with plenty of water.
1. To check the concentration you will need a hydrometer, which can be purchased at most auto parts stores.
2. When the engine has completely cooled down, unscrew the cap of the expansion tank of the cooling system. Following the instructions for using the hydrometer, check the density of the antifreeze. If the antifreeze is changed regularly, such problems should not arise, but if the density of the antifreeze is insufficient, it may be necessary to bring it to the appropriate level or change the coolant (see paragraph 32).
3. After completing the inspection, check the coolant level and tighten the expansion tank cap securely.
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