Hydraulic unit, brake servo/brake master cylinder - assembly overview (Bosch 8.0 / 8.2) — VW

VW
Fox
2004
Fox
2010
Fox
2014
SpaceFox
2011
Running gear
Brake systems
Edition
05.2014
Hydraulic unit, brake servo/brake master cylinder - assembly overview (Bosch 8.0 / 8.2)
The brake master cylinder and the brake servo may be independently replaced.
WARNING
Always replace self-locking nuts and bolts subject to angular torque
ABS control unit
J104
Remove and install
ABS hydraulic unit
N55
along with
ABS control unit
J104
Chapter
.
ABS hydraulic unit
N55
ABS reflux pump
V39
and the coupled valves may not be separated.
When replacing
ABS hydraulic unit
N55
, seal the old part with the plugs from the repair set number ET 1H0 698 311 A
Remove and install
ABS hydraulic unit
N55
along with
ABS control unit
J104
Chapter
.
Brake pipe connection
Hydraulic unit for right front brake caliper.
Identification in the hydraulic unit
VR
.
Brake pipe connection
for the left rear brake caliper.
Identification in the hydraulic unit
HL
.
Brake pipe connection
for the right rear brake caliper.
Identification in the hydraulic unit
HR
.
Brake pipe connection
Hydraulic unit for left front brake caliper.
Identification in the hydraulic unit
VL
.
Brake master cylinder connection
Brake master cylinder/floating plunger circuit for the hydraulic unit.
Identification in the hydraulic unit
HZ1
.
Brake master cylinder connection
Brake master cylinder/floating plunger circuit for the hydraulic unit.
Identification in the hydraulic unit
HZ2
.
Sealing
to brake servo.
Brake servo
On petrol engines, the vacuum required is removed from the intake manifold.
On diesel engines, a vacuum pump is installed to create vacuum.
Operation checking:
Press the brake pedal several times until the end with the engine stopped (This eliminates any remaining vacuum inside the device).
Now, keep the brake pedal pressed in the braking position with medium force and start the engine. When the brake servo is working properly, this can be felt with a foot on the brake pedal (the amplification is active).
In case of faults, replace completely.
Non-return valve (in the flexible vacuum line)
Chapter
.
separate from the brake pedal
Chapter
.
Self-locking hex head nut
Replace whenever removed
28 Nm.
Sealing ring
Replace whenever removed
Self-locking hex head nut
Replace whenever removed
20 Nm.
Brake master cylinder
cannot be repaired. Where faults occur, replace completely.
remove and install
Chapter
.
Retaining pin for the brake fluid reservoir
insert through the brake master cylinder.
Sealing plug
moisten with brake fluid and press into the brake master cylinder.
Sealing plug
connection to flexible vacuum line.
Brake fluid reservoir
Plug
Bolts
8 Nm.
Self-locking hex head nut
Replace whenever removed
20 Nm.
Support
Stud
Stud welded to the body.
Self-locking hex head nut
Replace whenever removed
20 Nm.
Stud
Stud welded to the body.
Support