Master Brake Cylinder

Master Brake Cylinder

Removing

Special tools, testers and auxiliary items required

• Torque Wrench 5-50 Nm (V.A.G 1331)

• Adapter (VAS 5234/1)

• Brake Charger/Bleeder Unit (VAS 5234)

• Sealing Plugs Repair Kit, Part no. (1H0 698 311 A)

Removing

- Remove the plenum chamber cover.

- Remove the engine cover.

- Remove the tower brace.

- Remove the plenum chamber.

- To protect against escaping brake fluid, place enough lint-free cloths in the area below the master brake cylinder.

- Extract as much brake fluid as possible from the brake fluid reservoir with the (VAS 5234).

• Brake fluid must never come into contact with fluids containing mineral oils (oil, gas, cleaning solutions). Mineral oil damages the sealing plugs and boots of the brake system.

• Brake fluid is poisonous. NEVER siphon brake fluid with your mouth! Also due to its corrosive effect, brake fluid must not come into contact with paintwork.

• Observe disposal regulations.

- Remove the brake fluid reservoir, refer to => [ Brake Fluid Reservoir ] Brake Fluid Reservoir.

- Disconnect brake lines - 2 - at brake master cylinder and seal brake lines with sealing plugs from repair kit.






- Remove brake master cylinder nuts - 3 -.

- Remove brake master cylinder from brake booster.

- Remove the brake master cylinder from the vehicle.

Do not let any brake fluid run into the brake booster.

Installing

Install in reverse order of removal.

Do not let any brake fluid run into the brake booster.

Use new nuts.

- Replace sealing ring between brake master cylinder and brake booster.

- When replacing brake master cylinder, ensure pressure rod in brake booster is seated correctly.

- Press brake pedal down slightly. This makes it easier to guide the push rod into the brake master cylinder.

- Install new nuts - 3 - and tighten. Note torque.






- Install brake lines - 2 - on brake master cylinder. Note torque.

- Install the brake fluid reservoir, refer to => [ Brake Fluid Reservoir ] Brake Fluid Reservoir.

- With manual transmissions, insert the clutch hydraulic line - 5 - into the brake fluid reservoir.






- Fill the brake fluid up to the marking.

- Bleed the brake system, refer to => [ Brake System, Bleeding ] Service and Repair.

- With manual transmissions, bleed the clutch.

- Install the plenum chamber bulkhead.

- Install the tower brace.

- Install the engine cover.

- Install plenum chamber cover.

- Perform ESP driving and system test.