The screw is a part of hydraulic brakes. The function of the element is to pump the hydraulics through the brake bleeder (pressure is restored) and air out (remove air bubbles).

1. IBIZA IV SC (6J1, 6P5)
2. IBIZA Mk IV SC (6J1, 6P5)
3. 80 (89, 89Q, 8A, B3)
4. 80 Saloon (89, 89Q, 8A, B3)
5. 4000 (89, 89Q, 8A, B3)
6. 100 (44, 44Q, C3)
7. 100 / 5000 (44, 44Q, C3)
8. 500 (44, 44Q, C3)
9. 100 (4A2, C4)
10. 100 Saloon (4A2, C4)
11. 500 (4A2, C4)
12. 80 (8C2, B4)
13. 80 Saloon (8C2, B4)
14. 90 (8C2, B4)
15. 80 Avant (8C5, B4)
16. 100 Avant (4A5, C4)
17. POLO (86C, 80)
18. GOLF II (19E, 1G1)
19. GOLF Mk II (19E, 1G1)
20. TRANSPORTER V Bus (7HB, 7HJ, 7EB, 7EJ, 7EF, 7EG, 7HF, 7EC)
21. See more in applications

The design of brake caliper screw

If we are talking about this part, it is also important to say a word about main malfunctions:

1. if the screw is damaged, if the plug is worn out, the part rusts and leaks;
2. if the caliper body is deformed as a result of an impact or a sharp collision with an obstacle;
3. screws for the brake system often break during non-professional (“garage”) pumping.

The part must be checked regularly for leaks and for obvious signs of rust. To pump and bleed hydraulic brakes, it is better to contact a car service.

Structurally, the TOPRAN brand Breather Screw/Valve, brake caliper is located in the upper part of the caliper chamber filled with brake fluid. When pumping with a pedal, the air in the system, in search of an outlet, rises to the top of the chamber. The mechanic unscrews the screw a little, allowing the air from the line to suffer a little. The procedure is carried out until the liquid completely displaces the gas.