Brake
rotor,
removing
and
installing
Brake
rotors
shouldalways
be
replaced
in
pairs
.
Fig
.
9
.
Brake
rotor
mounting
screw
(arrow)
.
3
.
Inspect
rotor
for
excessive
grooving,
cracks,
and
warp-
ing
.
Check
rotor
thickness
.
See
Table
b
.
4
.
Installation
is
reverse
of
removal
.
"
Clean
rotor
with
brakecleaner
before
installing
.
"
If
brake
fluid
hose
veas
removed
or
loosened,
brake
systemmustbe
bled
as
described
aboveunder
Bleeding
Brakes
.
BRAKES
340-
7
5
.
Once
brake
assembly
is
instalind,
depress
brakepedal
several
times
to
adjust
caliper
and
pads
.
"
Pedal
should
feel
firm
and
be
at
proper
height
.
"
Check
fluid
leve¡
.
Top
up
if
necessary
.
NOTE-
M3
models
use
directional
brake
rotors
and
mustbe
in-
NOTE-
stalled
on
the
proper
side
.
Part
numbes
are
cast
finto
When
installing
new
rear
brake
rotors,
the
parking
therotors
.
A
part
that
ends
in
an
odd
number
is
a
left
brakeshouldbe
adjusted
.
See
Parking
Brake
.
rotor
.
One
that
ends
in
an
even
number
is
a
right
rotor
.
1.
Remove
caliper
as
described-above
and
hang
from
Tightening
Torques
chassis
using
stiff
wire
.
"
Brake
rotor
to
wheel
hub
..........
16
Nm
(12
ft-Ib)
"
Front
brake
caliper
to
steering
arm
...
110
Nm
(81
ft-Ib)
NOTE-
"
Rear
brake
caliper
to
traíling
arm
....
67
Nm
(50
ft-Ib)
Do
notloosen
caliper
brake
hose
.
"
Road
wheel
to
hub
...
..
.
100
±
10
Nm
(74
t
7
ft-Ib)
2
.
Remove
mountingscrew
holding
rotor
to
wheel
hub
.
,
See
Fig
.
9
.
Table
b
.
Brake
Rotor
Reconditioning
Specificati*M`
Front
Rear
Vented
rotor
wear
limit
(min
.
thickness)
20
.4
mm
(0
.803
in.)
Solid
rotor
wear
limit
(min
.
thickness)
8
.4
mm
(0.331
in
.)
M3
models
wear
limit
(min
.
thickness)
26
.4mm
(0
.977
in
.)
18
.4
mm
(0
.723
in
.)
Axial
runout
(max
.)
rotor
removed
0
.05
mm
(0
.002
in
.)
0
.05
mm
(0
.002
in
.)
rotor
installed
0
.20
mm
(0
.008
in
.)
0
.20
mm
(0
.008
in
.)
CAUTION-
M3
brake
rotors
must
not
be
machined
.
MASTER
CYLINDER
The
brake
master
cylinder
is
mounted
to
the
front
of
the
vac-
uum
booster
on
the
driver
side
bulkhead
.
Master
cylinder,
removing
and
installing
1
.
Using
a
clean
syringe,
empty
brake
fluid
reservoir
.
WARNING
-
Brake
fluid
is
highly
corrosive
and
dangerous
to
the
environment
.
Dispose
of
it
properly
.
NOTE-
On
original
equipment
rotors,
the
mínimum
allowable
2
.
Disconnect
brake
fluid
leve¡
sender
connector
from
fluid
thickness
is
stamped
on
the
rotor
hub
.
Measure
the
rotor
reservoi
r
cap
.
brakingsurface
with
a
micrometer
at
eight
to
ten
different
points
and
use
the
smallest
measurement
recorded
.
3
.
Disconnect
brake
fluid
lines
frommaster
cylinder
.
See
Fig
.
10
.
Disconnect
hydraulic
clutch
system
supply
line
.
4
.
Unscrew
mounting
nuts
and
remove
master
cylinder
from
brake
booster
.
5
.
Make
sure
all
nuts,
fluid
couplings,
thread
bores,
and
mating
surfaces
are
clean
.
MASTER
CYLINDER
6
.
Disconnect
ABS
electrical
connectors
.
Label
and
then
disconnect
brake
lines
from
hydraulic
brake
unit
.
Plug
openíngs
.
See
Fig
.
12
.
~
~
A
1/
B
'1v
C
~
F
lu
11
-ri
J
.
0013244
A
.
Right
front
F
Front
from
master
cylinder
B
.
Leftfront
R
.
Rear
from
master
cylinder
C
.
Rear
Fig
.
12
.
Brake
fluid
linesat
ABS
hydraulic
unit
.
WARNING
-
"
On
cars
with
All
Season
Traction
(AST),
special
BMW
service
equipment
is
required
to
properly
bleed
the
Antilock
Brake
System
(ABS)
.
Removal
of
the
ABS
hydraulic
unit
is
not
recommended
un-
less
this
equipment
is
available
.
For
safetyrea-
sons,
the
brake
system
on
cars
with
ABS
must
not
be
bled
using
the
procedures
described
inthis
repair
group
.
"
Do
not
mix
up
the
fluid
fines
at
the
ABS
hydraulic
unit
Label
all
connections
before
disconnecting
.
7
.
Remove
ABS
hydraulic
unit
from
engine
compartment
.
8
.
Working
inside
car,
remove
panel(s)
frombeneath
steering
column
to
access
pedal
assembly
.
See513
In-
terior
Trim
.
12
.
Make
sure
al¡
nuts,
fluid
couplings,
thread
bores
and
mating
surfaces
are
clean
.
BRAKES
340-
9
0011261
Fig
.
13
.
Brake
pedal
clevispin
and
retaining
clip
(A)
.
Brake
booster
mounting
nuts
shown
at
arrows
.
13
.
If
necessary,
mount
master
cylinder
to
vacuum
booster
using
a
new
O-ríng
and
newself-locking
nuts
.
CAUTION-
Do
not
over-torque
the
master
cylinder
mounting
bolts
.
This
could
damage
the
brake
booster
and
prevent
proper
vacuum
build-up
.
14
.
Installation
is
reverse
of
Rmoval
.
"
Bleed
brakes
as
described
earlier
.
"
Check
and,
if
necessary,
adjust
brake
light
switch
above
brake
pedal
.
Tightening
Torques
"
Brakemaster
cylinder
to
brake
booster
...........
.
..
..
...
26
Nm
(18
ft-Ib)
"
Brake
booster
to
bulkhead
.
.
..
..
...
22
Nm
(16
ft-Ib)
"
Brake
fluidline
to
master
cylinder
or
ABS
hydraulic
unit
.......
.
..
17-19
Nm
(13-14
ft-lb)
9
.
Remove
clip
and
clevis
pin
from
brake
booster
pushrod
and
disconnect
it
from
brakepedal
.
Remove
brake
booster
mounting
nuts
.
See
Fig
.
13
.
NOTE-
10
.
Working
in
engine
compartment,
remove
brake
booster
When
replacing
the
brake
booster
one-way
valve
or
together
with
master
cylinder
.
vacuum
hose,
install
the
valve
so
that
the
molded
arrow
is
pointing
toward
the
intake
manifold
.
Use
new
hose
11
.
If
booster
or
master
cylinder
O-ring
is
being
replaced,
clamps
.
disconnect
master
cylinder
from
brake
booster
.
BRAKE
BOOSTER