2000 AUDI A4 brake fluid

47-29


Brake master cylinder with
23.81 mm (0.937 in.) piston
diameter and brake servo,
component summary Note:

Brake master cylinders and brake servos can
be replaced separately.
Brake master cylinders can no longer be
disassembled, i.e. there is no provision for
servicing.
Use only fresh brake fluid. Pay attention to
information on the brake fluid reservoir.
Brake line connections to master cylinder,
Bosch 5.0 ABS system ( page 45
-6 ), Bosch
5.3 system ( page 45
-18
).
1 -
T45 Torx
25 Nm (18 ft lb)
2 -
Self-locking nut 49 Nm (36 ft lb)
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ylinder with 23.81 mm
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) piston diameter and brake servo, com
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47-32


8 -
Gasket
9 -
Vacuum hose
Insert into brake servo
10 -
Brake fluid reservoir
11 -
Fluid reservoir cap
12 -
Sealing plugs
13 -
Supply hose Where applicableFrom brake fluid reservoir to clutch master
cylinder
14 -
Bulkhead
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ge 4 of 15 Brake master c
ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
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pair&id=AUDI.B5.SU03.47.6

47-34

Brake master cylinder with 23.81 mm
(0.937 in.) diameter piston, removing
and installing


Special tools and equipment
Sealing plugs from repair kit, Part No. 1H0 698
311A

CAUTION!

Part numbers are listed here for reference
only. Always check with your Parts
department for the latest information.

Removing

- Attach bleeder hose and bleeder bottle to left-
front brake caliper bleeder screw and open
bleeder screw.

- Operate brake pedal to pump out as much brake
fluid as possible.

- Close left-front bleeder screw.

- Cover engine compartment to catch any spilled
brake fluid.

CAUTION!
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ge 6 of 15 Brake master c
ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
ponent summar
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11/20/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.6

Brake fluid must not be allowed to come into
contact with paintwork because of its caustic
effect.
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ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
ponent summar
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.6

47-35


- On vehicles with manual transmission, disconnect clutch master
cylinder supply hose -1- and seal with plug.
- Disconnect harness connector from brake fluid level warning switch -2-.

- Disconnect brake lines -1- on brake master cylinder and seal brake
lines and threaded holes using plugs from repair kit.
- Remove brake master cylinder mounting nuts -2-.
- Carefully remove brake master cylinder from brake servo.
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ge 8 of 15 Brake master c
ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
ponent summar
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play?action=Goto&t
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pair&id=AUDI.B5.SU03.47.6

47-36

Installing
When installing, note the following points:

- When installing brake master cylinder onto
brake servo, make sure push rod is correctly
located in brake master cylinder.

- Apply slight pressure to brake pedal to move
push rod toward brake master cylinder; this
makes it easier to guide brake master cylinder
onto push rod.

Bleeding clutch hydraulics

- Connect US1116 brake bleeder but do not
switch on yet.

- Open bleeder screw on clutch slave cylinder.

- Attach collector bottle hose.

- Switch on bleeder unit and allow approx. 100 cc
(6 oz.) of brake fluid to flow out of clutch slave
cylinder.

- Close bleeder screw.

Pa
ge 9 of 15 Brake master c
ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
ponent summar
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.6

- Attach bleeder hose and bleeder bottle to left-
front brake caliper bleeder screw and open
bleeder screw.

- Operate brake pedal to pump out as much brake
fluid as possible.

- Close left-front bleeder screw.
Pa
ge 12 of 15 Brake master c
ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
ponent summar
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.6

47-38

- Cover engine compartment to catch any spilled
brake fluid.

CAUTION!

Brake fluid must not be allowed to come into
contact with paintwork because of its caustic
effect.

- On vehicles with manual transmissions, disconnect clutch master
cylinder supply hose -1- and seal with plug.
- Disconnect harness connector from brake fluid level warning switch -2-.

- Disconnect brake lines -1- on brake master cylinder and seal brake
lines and threaded holes using plugs from repair kit.
-
Remove T45 Torx bolts -2- from brake servo.- Disconnect vacuum hose from brake servo.
Pa
ge 13 of 15 Brake master c
ylinder with 23.81 mm
(0.937 in.
) piston diameter and brake servo, com
ponent summar
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU03.47.6