Brake Caliper Piston, Removing And Installing, Single-Piston Brake: Installing

Install the entire repair kit.
Only use mineral spirits to clean the brakes.
When a brake caliper piston or a piston cylinder are damaged, the brake caliper must be replaced.

-- Clean the surface of the brake caliper piston only with mineral spirits and let it dry.

-- Insert the seal into the brake caliper.

-- Insert the protective cap -A- into the Piston Resetting Tool - Cap /2:T10146/2 -item 1-.

Fig 1: Identifying Protective Cap And Assembly Tool T 10146/6

Courtesy of AUDI

-- Use the resetting tool and the Piston Resetting Tool:T10145 -item 2- to push the protective cap onto the brake caliper so that it contacts the brake caliper all the way around.

Fig 2: Identifying Protective Cap & Piston Resetting Tool T10145

Courtesy of AUDI

-- Check the protective cap seat:

Fig 3: Checking Seating Of Protective Caps

Courtesy of AUDI

The protective cap must no longer be able to be pulled out of the brake caliper by hand.

-- Lightly push the brake caliper piston at the protective cap and lock it in this position using the Trim Removal Wedge:3409 -item 2-, for example.

Fig 4: Blowing Compressed Air Into Protective Cap

Courtesy of AUDI

-- Blow compressed air on the protective cap (maximum 3 bar (43.51 psi)) -1-. The protective cap jumps onto the brake caliper piston while doing so.

Do not tilt the brake caliper piston so as not to damage the sealing boot.

-- Use the Piston Resetting Tool:T10145 -item 1- to push the brake caliper piston into the brake caliper.

Fig 5: Identifying Piston Pressed Into Brake Caliper Using Piston Resetting Tool

Courtesy of AUDI

Outer sealing lip of protective cap will then engage in the brake caliper piston groove.