AUDI A4 1999 B5 / 1.G Double Piston Front Caliper Workshop Manual

47-8


Double piston front brake
calipers, servicing Note:
CAUTION!
Install only the complete repair kit when
performing servicing work.
New brake calipers are filled with brake fluid
and pre-bled.
Apply a thin coating of assembly paste to brake
cylinders, pistons and seals.
1 -
Dust cap
Install on bleeder valve
2 -
Bleeder valve Apply a thin coating of assembly paste to
threads before installing
3 -
Brake caliper housing

Do not separate caliper housing halves
(internally serrated bolts).
If the protective boot for the guide pins is
damaged, replace brake caliper.
Pa
ge 1 of 5 Double
piston front brake cali
pers, servicin
g
11/20/2002 htt
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pair&id=AUDI.B5.SU03.47.3

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4 -
Seals
Use 3409 wedge to remove Fig. 2Install carefully by hand
5 -
Piston Piston diameter: 42.8 mm (1.69 in.)Use compressed air to remove from caliper
housing Fig. 1

Apply a thin coating of assembly paste
before installing Installing Fig. 3
, 4
and 5
6 -
Protective seal
Do not damage when installing pistonInstall outer sealing lip onto piston Fig. 3Install inner sealing lip into groove on brake
caliper housing Fig. 4

Pa
ge 2 of 5 Double
piston front brake cali
pers, servicin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.3

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Double piston brake caliper pistons,
removing and installing


Special tools and equipment

3409 wedge
Piston resetting tool

WARNING!
Note: Fig. 1 Pressing pistons individually out of brake caliper housing
using compressed air
Risk of accident! Apply pressure gradually. Guard against the
sudden release of the piston. Always wear safety glasses when carrying out this step.Insert brake pad -b- into piston. Place wooden block -a- into the space
so the pistons are not damaged. Only one piston can be pressed out at a time: hold the other piston
tight using the piston resetting tool in the brake caliper housing during
this step.
Pa
ge 3 of 5 Double
piston front brake cali
pers, servicin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.3

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Fig. 2 Removing seals using 3409 wedge

Fig. 3 Installing the outer sealing lip of the protective seal onto
the piston
Pa
ge 4 of 5 Double
piston front brake cali
pers, servicin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.3

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Note:
Hold the piston in front of the caliper housing for this procedure. Fig. 4 Installing inner sealing lip of protective seal using 3409
wedge

Note: Fig. 5 Pressing piston into brake caliper housing using piston
resetting tool
Install piston into the bore by hand and then install the brake pad -a-
on the piston before pressing piston into the brake caliper housing. The outer sealing lip of the protective seal will then locate in the piston
groove during this step.
Pa
ge 5 of 5 Double
piston front brake cali
pers, servicin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.3