The flange is an element of the vehicle cooling system. Its main task is to retain the coolant (antifreeze), preventing it from flowing out. For correct operation, the part must fit snugly against the engine. The element also prevents air from entering the system, ensuring a tight seal.

The 3RG brand Coolant Flange is located directly next to the engine, tightly fitting to it. The part is fixed with hardware.

1. 80 (8C2, B4)
2. 80 Saloon (8C2, B4)
3. 90 (8C2, B4)
4. A6 (4A2, C4)
5. A6 Saloon (4A2, C4)
6. A6 / S6 (4A2, C4)
7. A6 Avant (4A5, C4)
8. A6 / S6 Avant (4A5, C4)
9. 100 Avant (4A5, C4)
10. A4 (8D2, B5)
11. A4 Saloon (8D2, B5)
12. A4 / S4 (8D2, B5)
13. 80 Avant (8C5, B4)
14. A4 Avant (8D5, B5)
15. PASSAT (3B2)
16. PASSAT Saloon (3B2)
17. PASSAT Variant (3B5)
18. PASSAT Wagon (3B5)
19. PASSAT Estate (3B5)
20. A6 (4B2, C5)
21. See more in applications

The functionality of the coolant flange

Structurally, the flange is a part with an O-ring and a quick-release coupling. It connects the engine to hoses and pipes through which coolant circulates. Most parts are equipped with a rubber gasket. The flanges themselves are made of plastic or aluminum.

The flange is a simple element. However, it is he who is responsible for the tightness of the cooling system, and therefore for its efficient operation. As long as the flange fits snugly against the plane of the engine block, the system is functioning normally. As soon as the tee, which is deformed from overheating, and this will happen eventually, it will begin to leak and air the entire system.