Audi Workshop Service and Repair Manuals

Removing and installing piston for front brake caliper - FN-3 brakes Special tools and workshop equipment required t  Assembly paste -G 052 150 A2-

t  Removal wedge -3409-

t  Piston resetting appliance -T10145- Removing

–  Force piston out of brake caliper housing using compressed air.   Note Place a piece of wood in the recess to prevent damaging the piston.

–  Take out seal. –  To do so, use removal wedge -3409-.   Note When removing ensure that the bore of the cylinder is not damaged. Installing

–  Insert inner seal into groove -arrow- in brake caliper.

–  Push protective cap onto brake caliper housing and press it in so that it makes contact all round. –  At this stage it should not be possible to remove the protective cap from the brake caliper housing by hand. –  Apply a thin coat of assembly paste -G 052 150 A2- to piston and seal before inserting. –  Press brake piston lightly against protective cap. Keep the piston straight to avoid damaging the seal. –  Inflate protective cap with compressed air (maximum 3 bar). The protective cap will then locate around the brake piston.

–  Press brake piston into caliper using piston resetting appliance -T10145-. Keep the piston straight to avoid damaging the seal.   Note The inner sealing lip on the protective cap will then locate in the piston groove.