Table of contents: Checking for leaks in the cooling… ↓ Checking the coolant level ↓ Checking the density of antifreeze ↓ Checking the tension of the water… ↓ Replacing the coolant ↓
Perform the following procedures at the intervals given in Section "Maintenance" at the beginning of the Guide.
Checking for leaks in the cooling system
1. Inspect the condition of all coolant hoses, including heater hoses. Also check that the clamps are securely fastened.
Checking the coolant level
2. The coolant level can be checked through the transparent expansion tank. There is no need to remove the filler cap.
3. There is usually only one level mark on the side of the expansion tank, just below the seam, with a "minimum" mark and an arrow pointing to the "maximum" mark.
4. When the engine is cold, the coolant should be at the level mark, but when the engine is warm, the coolant should be slightly above the mark.
5. If necessary, remove the filler cap, add antifreeze mixture to the required level (photo). Note that if the engine is hot, cover the filler cap with a cloth, turn it one turn counterclockwise and release the pressure in the system. If a lot of coolant is required for topping up, allow the engine to cool completely before adding, otherwise there is a risk of damaging the cylinder head.
6. After refueling, install and tighten the filler cap.
7. If frequent topping up is required, but there is no visible leak in the system, it is recommended to check the pressure using a cooling system tester. Your Audi dealer has the necessary equipment to determine internal leaks in the engine.
Checking the density of antifreeze
8. It is important to maintain the correct density of antifreeze throughout the year. In addition to protecting the coolant from freezing, antifreeze also raises the boiling point. The recommended antifreeze mixture also includes a corrosion inhibitor, which prevents rust and scale from forming in the internal water passages of the engine.
9. The density of antifreeze can be checked using a special hydrometer, which can be purchased at motor parts stores.
Checking the tension of the water pump drive belt (4-cylinder engine)
10. See. Section 12 when checking and adjusting the generator drive belt.
Replacing the coolant
11. Audi does not specify a coolant change interval if the company's recommended G11 fluid is used. If any other antifreeze is used, see Chapters 3, 4 and 5, and replace it with the frequency given in "Technical maintenance" at the beginning of the guide.
(The original version of the article is posted on the website AudiManual)