FN3 Brake Caliper, Servicing
FN3 brake caliper, servicing
Special tools and workshop equipment required
^ VAG1331 Torque wrench (or equivalent)
^ VAG 1410 Torque wrench (or equivalent)
^ VAG 1869/2 Brake pedal depressor
Notes:
^ Install complete repair kit.
^ After replacing brake pads and with vehicle stationary depress brake pedal firmly several times so that the brake pads are properly seated in their normal operating position.
^ To draw off brake fluid from the reservoir, use a bleeder bottle, which is used only for brake fluid. Brake fluid is poisonous, NEVER siphon brake fluid with your mouth!
^ Wheel bolt tightening torque
1 - Brake hose
^ Do not disconnect brake hose when changing brake pads
2 - Protective cap
^ Remove
3 - Guide pins, 25 Nm
4 - Brake line, 15 Nm
^ Screw into brake caliper housing
^ Screw into brake hose, counter hold on brake hose hex.
^ Make sure that lugs are properly seated in retainer grooves.
5 - Brake caliper
^ Do not disconnect brake hose when changing brake pads
6 - Ribbed combi bolt, 120 Nm
^ Clean ribs if reusing
7 - Brake carrier
^ Bolt to wheel bearing housing
8 - Brake pads
^ Without wear indicator
^ Thickness 14 mm
^ Checking thickness
^ When worn always replace both sides
^ Wear limit: 7 mm including backing plate
^ The arrow on the inner pad (with spring) must point in the direction of brake disc rotation when moving forward. May create noises IT incorrectly installed.
^ There is an adhesive foil on the backplates of the outer brake pads. The protective foil must be pulled off before inserting.
9 - Retaining spring
^ Insert in both holes of brake caliper housing
Note: The retaining spring must be pressed under the brake carrier after inserting into both holes. Faulty installation will not allow compensation of outer pad wear. This will cause pedal travel to increase.
10 - Brake disc
^ Vented brake disc to vehicle identity No. 3B X 124 107: diameter 282.5 mm
^ Vented brake disc from vehicle identity No. 3B X 124 108: 282.5 mm
^ Brake disc thickness: 25 mm
^ Wear limit: 23 mm
^ When worn always replace both sides
^ Remove brake caliper prior to removing
11 - Retainer
^ Bolt to brake caliper housing
12 - Hex bolt, 10 Nm
13 - Brake pads
^ With wear indicator
- Warning lamp lights up on instrument panel when wear limit is reached (limit: 2 to 3 mm)
^ Thickness 14 mm
^ Checking thickness
^ Always replace both sides
^ Wear limit: 7 mm including backing plate
14 - Connector
^ For pad replacement remove from bracket -item 15
15 - Bracket
Brake pads removing and installing
Special tools and workshop equipment required
^ VAG 1331 Torque wrench (or equivalent)
^ Piston resetting tool
Removing
Note: When reusing brake pads mark location and install in same position, otherwise uneven braking will occur!
^ Remove protective caps -arrows-.
^ For vehicles with brake wear indicator disconnect the connector -1-.
^ Lift locking tab slightly on connector lower part -2- and then turn 90°
^ Pull connector lower part out of bracket.
^ Using a screwdriver pry off brake pad retaining spring from brake caliper housing and remove.
^ Remove both guide pins from brake caliper.
^ Remove brake caliper housing and lay to one side so that the weight of the brake caliper does not stress or damage the brake hose.
^ Remove brake pads out of brake caliper housing or from brake carrier.
Use only appropriate solvent for cleaning the brake caliper housing.
Installing
Note: Press piston back into the cylinder with resetting. Before inserting new brake pads, draw off brake fluid from the reservoir with a bleeder bottle. Before pressing the piston back, make sure reservoir has not been topped off, otherwise brake fluid will overflow and cause damage.
^ Press piston back into brake caliper.
^ Insert brake pad with retaining spring in brake caliper housing (piston).
Note: The inner pad (with spring) has an arrow. The arrow must point in the direction of the forward rotation of the disc brake. May create noises if incorrectly installed.
^ Remove protective foil on backing plate of outer brake pad.
^ Install outer brake pad to brake carrier.
^ Tighten brake caliper housing bolt to brake carrier with both guide pins.
^ Install both protective caps.
^ Install retaining spring into brake caliper housing.
^ Insert brake wear indicator connector into bracket on brake caliper.
The wiring for the brake wear indicator must be routed between the brake carrier and brake line.
Notes:
^ When inserting the outer brake pad, make sure that it does not stick to the brake caliper housing before achieving correct installation position.
^ Do not damage adhesive surface.
^ After replacing brake pads and with vehicle stationary, firmly depress brake pedal several times so that the brake pads are properly seated in their normal operating position.
^ Check brake fluid level after changing brake pads.