shifting BMW 325i 1994 E36 Workshop Manual

GENERAL
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210-1



CLUTCH
MECHANICAL
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210-3

CLUTCH
HYDRAULICS
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210-1



Clutch,
removing
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210-4

Clutch,inspecting
and
installing
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.210-5Clutch
hydraulic
system,



Transmission
pilot
bearing,replacing
.
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.
...
210-6
bleeding
and
flushing
.
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.
.......
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.....
210-2

Clutch
master
cylinder,
replacing
..
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.
...
210-2



Table

Clutch
slave
cylinder,
replacing
...
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210-3



a
.
Clutch
Disc
Diameter
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210-3

GENERAL



CLUTCH
HYDRAULICS

This
repair
group
covers
replacement
of
the
clutch
mechan-



The
Clutch
is
hydraulically
actuated
by
the
master
and
slave
¡cal
and
hydraulic
components
.
Special
tools
may
be
required



cylinders
.
Clutch
disc
wear
is
automatically
taken
upby
the
for
some
of
the
procedures
.
Read
the
procedure
through
be-



pushrod
travelof
the
slave
cylinder,
making
periodic
adjust-fore
beginning
a
job
.



ments
unnecessary
.

NOTE-

See200
Transmission-General
for
transmission
applicatíon
information
.

The
major
components
of
the
clutch
system
are
shown
in

Fig
.
1
.

Engine



Pressure
plate

flywheel,,
assembly

Clutch

Flywheel
bolt

Pressure
plate
release
lever



Release
lever

Fig
.
1
.



Clutch
assembly
and
hydraufcs
.

210
Clutch

Release
bearing

Pushrod

A
soft
or
spongy
feel
to
the
clutchpedal,
long
pedal
free-
play,
or
grinding
noises
from
thegears
while
shifting
can
all
in-
dicate
problems
with
the
Clutch
hydraulics
.
In
these
circum-
stances
it
is
best
to
start
with
a
clutch
fluid
flush,
followed,
if

necessary,
byreplacement
of
the
hydraulic
parts
.

From
brake
fluid
reservoir

CLUTCH
210-1

0

0

Transmission
inputshaft

Clutch
master
cylinder

Bulkhead

Slave
cylinder
6535

CLUTCH
HYDRAULICS

NOTE-

The
traction
control
system
referred
to
as
AST
(all
sea-
son
traction)
may
also
be
referred
to
as
ASC
(Automat-
ic
Stability
Control)
and
ASC+T
(Automatic
Stability
Control+Traction)
.

The
AST
system
improves
traction
by
electronically
apply-

ing
the
rear
brakes
when
therear
drive
wheels
are
spinning
at

a
faster
rate
than
the
front
wheels
.
The
combined
ABS/AST

control
module,
operating
through
the
ABS
hydraulic
control

unit,
modulates
braking
force
at
therear
wheels
.

In
addition,
AST
uses
retarded
ignition
timing
and
an
auxil-iary
engine
throttle
plate
to
reduceengine
torque
and
maintain

vehicle
stability
.

The
auxiliary
throttle
plate
is
held
open
by
spring
pressure
.

The
AST
system
actívates
the
auxiliary
throttie
position
motor

(ADS)
to
cose
the
AST
throttle
as
needed
.
This
reduces
the

volume
of
engine
intake
air
.
Due
to
the
throttle
closing
very
rapidly
during
AST
operationthe
driver
cannot
increase
theengine
power
output
regardless
of
how
far
theaccelerator
pedal
is
pushed
to
the
floor
.

The
auxiliary
throttle
plate
is
placed
ahead
of
the
conven-

tional
throttle
plate
in
the
throttle
body
.

Traction
control
also
comes
into
operationduringdecelera-
tion
.
Decelerating
on
snowy
or
icy
road
surfaces
can
lead
to
rear
wheel
slip
.
If
a
rear
wheel
startsto
drag
or
lock
up
when

the
throttle
is
closed
rapidly
orduringdownshifting,the
AST
system
can
limit
the
problem
by
advancing
the
ignition
timing
.

A
switch
on
the
center
console
is
used
to
togglethe
AST
on

or
off
.

The
AST
system
is
designed
to
be
maintenance
free
.
There

are
no
adjustments
that
can
be
made
.
Repair
and
trouble-
shooting
of
the
AST
system
requires
special
test
equipment

andknowledgeand
should
be
performed
only
by
an
autho-

rized
BMW
dealer
.
Table
a
lists
theconditions
indicated
by

the
AST
indicator
light
in
the
instrument
cluster

SUSPENSION,
STEERING
AND
BRAKES-GENERAL



300-5

Tablea
.
AST
Indicator
Lamp
Function

Indicator
lamp



1
Condition



1
Comment

Light
on



Normal
AST
start-



Automatic
AST
up



self-test

Light
off



AST
monitoring



Automatic
AST
op-
mode



eration

Press
AST
button,



AST
off
(disabled)



Rocking
the
car
tolight
comes
on



getout
of
snow
or
other
loose
surface
Driving
with
snow
chains

Press
AST
button
:



AST
monitoring



Automatic
AST
op-
light
goes
out



I
mode



eration

Light
flashes



AST
active
mode



I
Normal
AST
oper-
ation
as
it
controls
wheel
speed

Light
stays
on
af-



Defect
in
AST



Consult
BMW
ter
start
up
or



dealer
for
diagno-
comes
on
while



sis/repair
driving



(Vehicle
operation
remains
normal)

WARNING
-

Even
a
car
with
AST
is
subject
to
the
normal
physi-
cal
laws
.
Avoid
excessive
speeds
for
the
road
con-
ditions
encountered
.

CAUTION-
"
If
the
tires
on
the
carare
of
different
makes,
the
AST
system
may
over-react
.
Only
fit
tires
of
the
same
make
and
tread
pattem,

"In
adverse
conditions,
such
as
trying
to
rock
the
car
outof
deep
snow
or
another
soft
surface,
or
when
snow
chainsare
fitted,
it
is
advisable
to
switch
off
AST
and
allow
the
cars
driveline
to
op-
erate
conventionally
.

INTEGRATED
SYSTEMS