1997 BMW 325i air conditioning

General
Data
and



010
FundamentalsfortheDo-lt-YourselfOwner

Maintenance



020
Maintenance
Program

Engine

Transmission

Suspension,

Steering
and

Brakes

4
Body

100
Engine-General

110



Engine
Removal
and
Installation
113



Cylinder
Head
Removal
and
Installation
116



Cylinder
Head
and
Valvetrain
117



Camshaft
Timing
Chain

119



Lubrication
System

200
Transmission-General
210
Clutch
230
Manual
Transmission

510



Exterior
Trim,
Bumpers



520



Seats

Bo
y
Equipment



512
DoorWTdws



540



nr
t

513



InteriorTrim



541



Convertible
Top

515



Central
Locking
and
Anti-Theft

600



Electrical
System-General



620



Instruments

Electrical
S



stem
610
Electrical
Component
Locations



630
Exterior
Lighting

611



Wipers
and
Washers



640



Heating
and
Air
Conditioning

6



612



Switches
and
Electrical
Accessories



650



Radio

Equipment
and



720
SeatBelts

Accessories



721
Airbag
System
(SRS)

Electrical
Wiring

Diagrams

Foreword
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Warnings
and
Cautions
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..
back
of
book

300



Suspension,
Steering
and



330



RearSuspension

Brakes-General



331



Final
Drive

310



Front
Suspension



340



Brakes

320



Steering
and
Wheel
Alignment

400
Body-General



411
Doors

410



Fenders,
Engine
Hood



412



Trunk
Lid

120



Ignition
System
121



Battery,Starter,
Alternator
130



Fue¡
Injection
160



Fuel
Tank
and
Fuel
Pump
170



Radiator
and
Cooling
System180



Exhaust
System

240



Automatic
Transmission
250



Gearshift
Linkage

260
Driveshaft

Please
read
these
warnings
and
cautions

before
proceeding
with
maintenance
and
repair
work
.

WARNING-



"
Friction
materials
(such
as
brake
pads
or
shorts
or
clutchdiscs)
contain
asbestos
fibers
or
other
friction
materials
.
Do
notcreate
"
See
also
Cautionson
page
viü



dustby
grinding,
sanding,
orby
cleaning
with
compressed
air
.

"
Some
repairs
may
be
beyond
your
capability
.
If
you
lack
the



Avoid
breathing
dust
.
Breathing
any
friction
material
dust
can
lead

skills,
tools
and
equipment,
or
a
suitable
workplace
for
any
proce-



to
serious
diseases
and
may
result
in
death
.

duredescribed
in
this
manual,
we
suggestyou
leave
such
repairs



"
Batteries
give
off
explosive
hydrogen
gas
during
charging
.
to
an
authorized
BMW
dealer
service
department
or
other
quali-



Keep
sparks,
lighted
matches
and
open
flame
away
from
the
top
fied
shop
.



of
the
battery
If
hydrogen
gas
escaping
from
the
cap
vents
is

"Do
not
re-use
any
fasteners
that
are
worn
or
deformed
in
normal



ignited,
it
will
ignite
gas
trapped
in
the
cells
and
cause
the
battery

use
.
Many
fasteners
are
designed
to
be
used
only
once
and



to
explode
.

become
unreliable
and
may
fail
when
used
a
second
time
.
This



"
Connect
and
disconnect
battery
cables,
jumper
cablesora
bat-
includes,
but
is
not
limited
to,
nuts,
bolts,
washers,
self-locking
nuts
or
bolts,
circlips
and
cotterpins
.
Always
replace
these
fasteners

with
new
parts
.
"Do
not
quick-charge
the
battery
(for
boost
starting)
for
longer
"
Never
work
under
a
lifted
car
unless
it
is
solidly
supportedon



than
one
minute
.
Wait
at
least
one
minute
before
boosting
the
bat-
stands
designed
for
the
purpose
.
Do
not
support
a
car
on
cinder



tery
a
second
time
.
blocks,
hollow
tiles
or
other
props
that
may
crumble
under
contin-

uous
load
.
Never
work
under
acar
that
is
supported
solely
by
a



"Do
not
allow
battery
charging
voltage
to
exceed
16
.5
volts
.
If
the

jack
.
Never
work
under
thecar
while
the
engine
is
running
.



battery
beginsproducing
gas
or
boiling
violently,
reduce
the
charg-
ing
rate
.
Boosting
a
sulfated
battery
at
a
high
charging
rate
can
"
If
you
are
going
to
work
under
acar
on
the
ground,
make
sure



cause
an
explosion
.
that
the
ground
is
level
.
Block
the
wheels
to
keep
the
carfrom
roll-

ing
.
Disconnect
the
battery
negative
(-)
terminal
(ground
strap)to



"
The
air-conditioning
system
is
filled
with
chemical
refrigerant,

prevent
others
from
starting
thecar
while
youare
under
it
.



which
is
hazardous
.
TheA/C
system
should
be
servicedonly
by

trained
technicians
using
approved
refrigerant
recovery/recycling
"
Never
run
the
engine
unless
the
work
area
is
well
ventilated
.



equipment,
trained
in
related
safetyprecautions,
and
familiar
with
Carbon
monoxide
kills
.



regulations
governing
the
discharging
and
disposal
of
automotive

"
Finger
rings,
bracelets
and
other
jewelry
shouldbe
removed
so



chemical
refrigerants
.

tery
charger
only
with
the
ignition
switched
off,
to
prevent
sparks
.

Do
not
disconnect
the
battery
while
the
engine
is
running
.

that
theycannot
cause
electrical
shorts,
get
caught
in
running



"
Do
not
expose
any
partof
the
A/Csystem
to
high
temperatures
machinery,
or
be
crushed
by
heavy
parts
.



suchas
open
flame
.
Excessiveheat
will
increase
system
pressure

"
Tie
long
hair
behind
your
head
.
Do
not
wear
a
necktie,
a
scarf,



and
may
cause
the
system
to
burst
.

loose
clothing,
or
a
necklace
when
you
work
near
machine
tools
or



"
Some
aerosol
tire
inflators
are
highly
flammable
.
Be
extremely
running
engines
.
If
your
hair,
clothing,
or
jewelry
were
to
get
caught



cautious
when
repairing
a
tire
that
may
havebeen
inflated
using
in
the
machinery,
severe
injury
could
result
.



an
aerosol
tire
inflator
.
Keep
sparks,
open
flame
or
other
sources

"
Do
not
attempt
to
work
onyourcar
if
you
do
not
feel
well
.
You



of
ignition
away
from
the
tire
repair
area
.
Inflate
and
deflate
the
tire

increase
the
danger
of
injury
toyourself
and
others
if
you
are
tired,



at
least
four
times
before
breaking
the
bead
from
therim
.
Com-

upset
or
have
takenmedication
or
any
other
substance
that
may



Pletely
remove
the
tire
from
the
rim
beforeattempting
any
repair
.

keep
you
from
being
fully
alert
.

"
Illuminate
your
work
areaadequately
but
safety
.
Use
a
portable

safety
light
for
working
inside
or
under
thecar
.
Make
surethe
bulb

is
enclosedbya
wire
cage
.
The
hot
filament
of
an
accidentally
bro-

ken
bulb
can
ignite
spilled
fuel
or
oil
.

"
Catch
draining
fuel,
oil,
orbrake
fluid
in
suitable
containers
.
Do

not
use
food
or
beverage
containers
that
mightmislead
someone

into
drínking
from
them
.
Store
flammable
fluids
away
from
fire
haz-

ards
.
Wipe
up
spills
at
once,
but
do
not
store
the
oily
rags,
which

can
ignite
and
burn
spontaneously
.

"
Always
observe
good
workshop
practices
.
Wear
goggles
when

youoperate
machine
tools
or
work
with
battery
acid
.
Gloves
or

other
protectioeclothing
should
be
worn
whenever
thejob
requires

working
with
harmful
substances
.

"
Greases,
lubricants
and
other
automotive
chemicals
contain

toxic
substances,
many
of
which
are
absorbed
directly
through
the

skin
.
Read
the
manufacturer's
instructions
and
warnings
carefully
.

Use
hand
andeye
protection
.
Avoid
direct
skin
contact

"
Cars
covered
by
this
manual
are
equipped
with
a
supplemental

restraint
system
(SRS),
that
automatically
deploys
an
airbag(s)
in

theevent
of
a
frontal
ímpact
.
The
airbag(s)
is
inflated
byan
explo-

sive
device
.
Handled
improperly
or
without
adequate
safeguards,

can
be
accidently
activated
and
cause
serious
injury
.

"
The
ignition
system
produces
high
voltages
that
can
be
fatal
.

Avoid
contact
with
exposed
terminals
and
use
extreme
care
when

working
ona
car
with
the
engine
running
or
the
ígnition
switched
on
.

"
Place
jack
stands
only
at
locations
specified
bymanufacturer
.

The
vehicle
lifting
jacksupplied
with
the
vehicle
is
intended
for
tire

changes
only
.
A
heavy
duty
floor
jack
shouldbe
used
to
lift
vehicle

before
installing
jack
stands
.
See
010
Fundamentals
for
theDo-
.

it-Yourself
Owner
.

"
Battery
acid
(electrolyte)
can
cause
severeburns
.
Flush
contact

area
with
water,
seek
medical
attention
.

"
Aerosolcleaners
and
solvents
may
contain
hazardous
ordeadly
vapors
and
are
highly
flammable
.
Use
only
in
a
wellventilated

area
.
Do
not
use
on
hot
surfaces
(engines,
brakes,
etc
.)
.

"
Disconnect
the
battery
negative
(-)
terminal
(Ground
strap)



"
Do
not
remove
coolant
reservoir
or
radiator
cap
with
theengine

whenever
you
work
on
the
fuel
system
orthe
electrical
system
.
Do



hot
.
Danger
of
bums
and
engine
damage
.

not
smoke
or
work
near
heaters
or
other
fire
hazards
.
Keep
an

approved
fire
extinguisher
handy
.



continued
on
next
page
vii

Table
b
.
Inspection
I
Service

MAINTENANCE
PROGRAM
020-5

ad

d
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ID

a



r



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r
E
R
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L-



0
Maintenance
ítem



1



z



3
~



c
d

Engine
compartment
maintenance

Change
oil
and
oil
filter
.

Check
brake/clutch
fluid
leve¡

Check
battery
acid
leve¡
and
correct
asnecessary
.
Repair
Group
121

Check
engine
coolant
level
and
anti-freeze
protection
and
addasnecessary
.
Inspect
for
cooling
system
leaks
.
Repair
Group
170

Lubricate
throttie
linkage

Under
car
maintenance

Check
transmission
for
externa¡
leaks
.

Check
manual
transmission
oil
leve¡
andadd
asnecessary
.
Repair
Group
230

Check
final
drive
lubricant
and
addasnecessary
.

Check
fue¡
tank,
fuel
lines,
and
all
connections
for
leaks
.

Inspect
exhaust
system
.
Repair
Group
180

Check
steeringrack
and
steeringlinkages
.
Check
power
steering
system
for
leaks
.
Check
(luid
leve¡
.
Repair
Group
320

Inspect
brake
system
for
damaged
hoses
and
fines,
leaks
or
damage
.
Remove
calipers
and
check
brake
pad
wear
.
Check
brake
rotors
for
scoring
damage
.
Repair
Group
340

Check
parking
brake
operation,
adjust
cable
if
necessary
Repair
Group
340

Inspect
front
and
rear
suspension,
including
wheel
bearings,
for
play
.
Repair
Group
320/330

Inspect
wheelsand
tires,
including
spare,
check
tire
pressure
and
condition

Body
and
Interior
Maintenance

Lubricate
door
hinges
and
hood
latch,
hood
hinges

Check
headlight
and
driving
light
aiming
and
adjust
as
necessary
.

Check
operation
of
headlights,
parking
lights,
back-up
fights,
licenseplate
lights,
interior
lights,
glove
box
light,
engine
compartment
light,
trunk
light,
instrument
panel
lights,
turnsignals,
emer-gency
flashers,
stop
fights,
horas,
headlight
flasher
and
dimmer
switch

Replace
ventilation/A/C
micro-filter
.
Check
functionof
air
conditioning
.
Repair
Group
640

Check
function
of
seat
belts
.
Repair
Group
720

Check
tightness
of
mountfng
screws
on
airbag
front
crash
sensors
(Airbag
I)
.
Repair
Group
721

Check
windshield
washer
fluid
leve¡
and
concentration,
add
as
necessary
Check
operation
of
washer
system
.
Check
condition
of
wiperblades
.
Repair
Group
611

Tighten
nuts
and
bolts
for
door
locks
and
striker
plates

Replace
batteries
for
alarm/remote
control
in
masterkey(where
applicable)
.

Road
Test

Check
braking
performance,
steering,
HVAC,
manual
or
automatic
transmission,
and
mirrors

Service
Interval
Reset

Reset
service
indicator
using
specialreset
tool
.

MAINTENANCE
TALES

d
a
d
_
L

G>
G1
a
N
.






G1
Ñ



N
N
O
.
r
d

Maintenance
ítem



°
~



Z



~
i
I
D
i
Body
and
Interior
Maintenance
(cont
.)

Replace
ventilation/A/C
micro-filter
.
Check
function
of
air
conditioning
.
Repair
Group
640

Check
function
of
seat
belts
.
Repair
Group
720

Check
windshield
washer
fluid
level
and
concentration,
add
asnecessary
.
Check
operation
of
washer
system
.
Check
condition
of
wiperblades
Repair
Group
611

Tighten
nuts
and
belts
for
door
locks
and
striker
plates
.

Replace
batteries
for
alarm/remote
control
in
masterkey
(where
applicable)
.

Check
ground
connection
(mounting
screws)
of
SRS
(airbag)
front
sensor
to
body,
if
applicable
.
Repair
Group
721

Road
Test

Check
braking
performance,
steering,
HVAC,
manual
or
automatic
transmission,
and
mirrors

Service
Interval
Reset

Reset
service
indicator
using
specialreset
tool
.

Maintenance
ítem

Replace
oxygen
sensor
.
Repair
Group
180
1992-1994
1995-
on

Flush
and
replace
brake
fluid/clutch
fluid
.
Repair
Group
340

Drain
and
flush
cooling
system
and
replace
coolant
.
Repair
Group
170
1992-19961997-1998

Anti-corrosion
warranty
inspection
.

Tablec
.
Inspection
II
Service
(continued)

Cabled
.
Scheduled
Maintenance-Time/Mileage
Intervais

MAINTENANCE
PROGRAM
020-7

e
~
e
e

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r
NM
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Ó

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Ñ
1
ZG

NN

MAÍNTENANCE
TABLES

110-
4



ENGINE
REMOVAL
AND
INSTALLATION

Engine,
removing
and
installing

(6-cylinder
engines)

Engineremoval
procedures
for
the
various
6-cylinder
en-

gines
arecovered
in
this
section
.
Most
steps
in
theproce-

dures
are
similar
or
the
same
for
al¡
engines
.
Specific

differences
that
apply
are
noted
at
the
beginning
of
each
step
.

Be
sure
to
cover
all
painted
surfaces
before
beginning
the

removal
procedure
.
As
an
aid
to
installation,
label
all
compo-

nents,wires,
and
hoses
before
removing
them
.
Do
not
reuse

gaskets,
O-rings
or
seals
during
reassembly
.

WARNING
-

Due
to
risk
of
personal
injury,
be
sure
the
engine
is
cold
before
beginning
the
removalprocedure
.

1
.
Disconnect
negative
(-)
battery
cable
in
luggage
com-

partment
.

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
vi¡¡
.

2
.
Remove
engine
hood
or
place
hood
in
service
position
.

See410
Fenders,
Engine
Hood
.

NOTE-

1t
is
not
necessary
to
remove
the
engine
hood,
but
it
is
helpful
and
will
make
engine
removal
and
installation
easier
.

3
.
Remove
splash
guardunder
engine,
if
applicable
.

4
.
Remove
transmission
from
car
.
See
230
Manual

Transmission
or
240Automatic
Transmission
.

5
.
Remove
vacuum
hosefrom
brake
booster
on
bulkhead
.

Cover
hole
in
booster
and
plug
hose
end
.

6
.
Remove
intake
air
plenum
panel
in
rear
of
engine
com-
partment
.
See
640
Heating
and
AirConditioning
.

7
.
Remove
ground
strap
from
timing
case
cover,
if
appli-

cable
.

8
.
Remove
top
enginecovers
and
disconnect
ignition
coil
harness
connectors
.
Working
at
fuel
injectors,
pry
open
small
wire
clipsat
each
injector
.
Remove
main
harness

hold-down
nuts
and
lift
completeharness
away
.
See
Fig
.
7
.

ENGINE
REMOVAL
AND
INSTALLATION

Fig
.
7
.



Remove
mainharnessfrom
top
engine
and
place
at
base
of

windshield
.

0012703

Fig
.
8
.



Mass
air
flow
sensor
connector
air
duct
hose
clamp,
and
air
cleaner
housing
mounting
bolts
(arrows)
.

9
.
Unbolt
andremove
complete
air
cleaner
housing
with



10
.
On
cars
with
automatic
transmission,
remove
front
and
mass
air
flow
sensor,
disconnecting
and
labeling
con-



rearbrackets
holding
transmission
cooler
linesto
side
nectors,
ducting
and
hoses
asnecessary
.
See
Fig
.
8
.



of
engine
.

113
Cylinder
Head
Removal
and
Installation

GENERAL
.
...............
.
.
.
.
.
.......
113-1



CYLINDER
HEAD,
6-CYLINDER
.
.
.
.
.
.
.
113-10

Cylinder
head,
removing
(6-cylinder
engine)
..
113-10
CYLINDER
HEAD,
4-CYLINDER
..
.
...
.
.
113-1



Cylinder
head,
installing
(6-cylinder
engine)
...
113-15
Cylinder
head,
removing
(4-cylinder
engine)
...
113-1



E
Cylinder
head,
installing
(4-cylinder
engine)
...
113-6

GENERAL



CYLINDER
HEAD,
4-CYLINDER

The
information
given
inthis
repair
group
assumes
that
the

engine
is
installed
in
the
engine
bay
.
For
cylinder
head,
cam-



Cylinder
head,
removing

shaft,
and
valvetrain
disassembly
and
reconditioning
informa-



(4-cylinder
engine)
tion,
see116
Cylinder
Head
and
Valvetrain
.

For
ease
of
use
this
removal
procedure
is
broken
into
sub-
In
the
procedures
given
below,
engines
are
referred
to
by



sections,
as
follows
:
engine
code
.
If
necessary,
see100
Engine-General
for
en-

gine
code
and
application
information
.

NOTE-

If
a
head
gasket
problem
is
suspected,
acompression
test
will
usually
detectthe
fault
.
See
100
Engine-Gen-
eral
for
compression
testing
information
.

Special
BMW
service
tools
are
required
to
properly
remove
and
install
the
cylinder
head
on
both
the
4-cylinder
and
6-cyl-

inder
engines
.
The
special
tools
are
used
to
time
the
val-

vetrain
to
the
crankshaft
and
to
remove
the
Torx
(El
2)
head

bolts
.
Read
the
procedure
through
before
beginning
thejob
.

Cover
al¡
painted
surfaces
before
beginning
the
removal

procedure
.
As
an
aid
to
installation,
label
all
components,

wires,
and
hoses
before
removing
them
.
Do
not
reuse
gas-

kets,
O-rings
or
seals
during
reassembly
.

WARNING
-

Due
to
risk
of
personal
injury,
be
sure
the
engine
is
cold
before
beginning
the
removalprocedure
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-1

General
Coolingsystem,
draining
Cylinder
head
cover,
removing

Intake
manifold,
removing

Timing
chains,
uncoupling

Cylinder
head
assembly,
removing

WARNING
-

Allow
engine
to
cool
before
beginning
this
proce-
dure
.

General

1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION
-

"
Prior
to
disconnectiog
the
battery,
read
the
bat-
tery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.

"
Disconnecting
the
battery
may
erase
fault
codees)

stored
in
control
module
memory
.
Check
for
fault

codes
using
special
BMW
diagnostic
equipment
.

NOTE-

The
battery
is
mounted
in
the
luggage
compartment
behind
the
right
side
trim
panel
.

2
.
Working
underneath
vehicle,
remove
front
exhaust
pipe

from
exhaust
manifold
.
See
Fig
.
1
.

3
.
Disconnect
vacuum
hose
fitting
from
brake
booster
on

rear
bulkhead
.
Plug
opening
in
booster
and
hose
end
.

CYLINDER
HEAD,
4-CYLINDER

113-10



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

Tightening
Torques

"
Coolant
drain
plug
to
cylinder
block
.
.
25
Nm
(18
ft-1b)

"
Intake
manifold
support
to
manifold
.
.
15
Nm
(11
ft-Ib)

"
Lower
intake
manifold

to
cylinder
head
.
..........
.
..
...



15
Nm
(11
ft-Ib)

"
Lower
intake
manifold

to
upper
manifold
..........
.
..
...
15
Nm
(11
ft-Ib)

"
Radiator
cooling
fan
to
coolant
pump
.
40
Nm
(30
ft-Ib)

"
Radiator
drain
screw
to
radiator
...
.
2
.5
Nm
(22
in-lb)

CYLINDER
HEAD,
6-CYLINDER

For
ease
of
use
this
procedure
is
broken
into
subsections,

as
follows
:

General
Coolingsystem,
draining
Cyiinder
head
cover,
removing

Intake
manifold,
removing

Timing
chains,
uncoupling

Cylinder
head
assembly,
removing

WARNING
-

Allow
the
engine
to
cool
before
beginning
this
pro-
cedure
.

General

1
.
Working
inside
luggage
compartment,
disconnect
neg-
ative
(-)
battery
cable
.

CAUTION-

"
Prior
to
disconnectiog
the
battery,
read
the
bat-
tery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
vi¡¡
.

"
Disconnecting
the
battery
may
erase
fault
code(s)
stored
in
control
module
memory
.
Check
for
fault
codes
using
special
BMW
diagnostic
equipment

2
.
Remove
front
exhaust
pipes
from
manifolds
.
Discard
nuts
.

3
.
Remove
air
filter
housing
complete
with
mass
air
flow
sensor
and
intake
air
ducting
.
Disconnect
vacuum
hos-
es
from
throttle
housing
.

4
.
On
M52
and
S52US
engines
:
Remove
secondary
air
injection
check-valve
from
front
of
engine
and
set
aside
.

CYLINDER
HEAD,
6-CYLINDER

Coolingsystem,
draining

5
.
Drain
engine
coolant
and
Rmove
coolant
hoses
from

thermostat
housing
.
Drain
engine
block
by
removing

block
drain
.
See
170
Radiator
and
Cooling
System
.

NOTE-

The
block
drain
is
on
the
exhaust
side
of
the
engine,
near
cylinder
no
.
5
.

6
.
Remove
radiator
cooling
fan
and
fan
shroud
.
See
170

Radiator
and
Cooling
System
.

NOTE-

The
radiator
cooling
fannut(32
mm
wrench)
has
left-
hand
threads
.

Cylinder
head,
removing

(6-cylinder
engine)



7
.
Disconnect
heater
hoses
at
rear
of
cylinder
head
.
See

Fig
.
26
.

'i

8
.
Remove
alternator
cooling
duct
.

Cylinder
head
cover,
removing

0012687

Fig
.
26
.
Disconnect
heater
hoses
at
heater
valve
(A)
and
heater
core
(B)
.

9
.
Remove
air
plenum
from
rear
of
engine
compartment
.

See640
Heating
and
Air
Conditioning
.

10
.
Remove
plastic
cylinder
head
covers
from
above
fuel
injectors
and
ignition
coils
.
Pull
larger
cover
forward

when
removing
.
See
Fig
.
27
.

11
.
Disconnect
crankcase
ventílation
hose
fitting
from
cyl-
inder
head
cover
.

12
.
Disconnect
ignition
coil
harness
connectors
from
coiis
.

Remove
ignition
coiis
and
spark
plugs
.
See
120
Igni-
tion
System
.

GENERAL

CYLINDER
HEAD,

DISASSEMBLY
AND
ASSEMBLY
CYLINDER
HEAD
AND
VALVETRAIN



116-1

116
Cylinder
Head
and
Valvetrai
n

GENERAL
.
.....
.
.
.
...
.
.
.
.
.
.
.
.
.
.......
116-1



Hydraulic
cam
followers,
checking
and
replacing
(M42
and
al¡
6-cylinder
engines)
.
...
.....
.
..
116-9
CYLINDER
HEAD,



Valve
guides
.
.
.
...
.
.
.
.
.
.
...
.
.
.
.
.
.
.
.
.
.
116-10
DISASSEMBLY
AND
ASSEMBLY
...
.
...
116-1



Valves
.
.
.
.
.
.
.
.
.
.
.
.
.
...
.
...
.
.
.
.
.
...
.
.
116-11
Camshafts,
removing
and
installing

(M42
engine)
....
.
....
.
.
.
.
.
.
.
.
.
.....
.
.
116-1



Valves,
leak
test
.
.
.
.
.
.
.
.
.
.
...
.
.
.
.
.
.
.
.
.
.
116-11

Camshafts,
removing
and
installing



Valve
stem
oil
seals
.
.
.
.......
.
.
.
.
.
...
.
.
116-11

(M44
engine)
.........
.
.
.
.
.
.
.
.
.
.......



116-3



Valve
seats



.
.
.
.
.
.
.
.
.
...
.
...
.
.
.
.
.
...
.
.116-12

Camshafts,
removing
and
installing



Valve
springs
.
.
.
.
.
.
.
.
...
.
...
.
.
.
.
.
.....
116-12

(6-cylinder
engine)
.....
.
.
.
.
.
.
.
.
.
.......
116-4

Valves,
removing
and
installing
........
.
....
116-6



TABLES

CYLINDER
HEAD
AND
VALVETRAIN,



a
.
Cylinder
Head
Height
........
....
.
..
..........
116-7

RECONDITIONING
.
...
.
.
.
.
.
.
.
.
.
.......
116-7



b
.
Camshaft
Specifications
.......
..
.
..
........
.116-7

Cylinder
head
...
.
.
.
...
.
.
.
.
.
.
.
.
.
....
.
..
116-7



c
.
Valve
Guide
Specifications
....
...
.
..
........
116-10
d
.
Valve
Specifications
...........
..
.
..
........
116-11
Camshaft
.
.
.
.
.
.
.
.
.
.
.
.
.
.
...
.
.
.
.
.
.......
116-7



e
.
Valve
Seat
Dimensions
.........
.
..
..
......
.116-12
Hydraulic
valve
adjusters,

checking
and
replacing
(M44
engine)
..
.
.
.
116-8

Camshafts,
removing
and
installing

(M42
engine)

This
repair
group
covers
cylinder
head
and
valvetrain
ser-
vice
and
repair
.
Most
of
the
repairs
described
here
require
that



The
camshafts
can
be
removed
with
the
cylinder
head
the
cylinder
head
first
be
removed
as
described
in
113
Cylin-



mounted
on
the
engine
.
The
first
step
is
to
remove
the
cylinder
der
HeadRemoval
and
Installation
.



head
cover
.
See
113
Cylinder
HeadRemoval
and
Installa-

tion
.

NOTE-



Special
BMW
service
tools
should
always
be
used
to
remove

"
For
timing
chain
and
VANOS
repair
information,
see



and
install
the
camshafts
.
Removal
and
installation
of
the
cam-
117
Camshaft
Timing
Chain
.



shafts
without
the
special
tools
can
result
in
camshaft
and
valve

"
If
it
is
determined
that
the
cylinder
head
will
require



train
damage
.

significant
reconditioning
work,
a
remanufactured
cyl-

inder
head
may
bea
good
alternative
.
Remanufac-



WARNING-

tured
cylinder
heads
are
available
froman
authorized



The
process
of
evenly
loosening
the
camshaftbear

BMW
dealer
.



ing
cap
nuts
is
NOT
an
acceptable
method
of
re-
moving
the
camshafts
.
Be
sure
to
read
the

The
information
given
in
this
repair
group
is
organized
ac-



procedure
through
before
starting
the¡ob
.

cording
to
engine
code
.
For
engine
applicationinformation,

see100
Engine-General
.



1
.
Disconnect
negative
(-)
battery
cable
.

CAUTION-

Prior
to
disconnectiog
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manualonpage
viii
.

BMW
special
tools
are
required
for
most
cylinder
head
ser-



2
.
Remove
radiator
cooling
fan
shroud
and
cooling
fan
.
vice
described
in
this
repair
group
.
Many
of
these
tools
areex-



See
170
Radiator
and
Cooling
System
.
pensive
and
only
available
through
an
authorized
BMW
dealer
.
If

the
special
tools
are
not
available,
one
altematve
is
to
remove

the
cylinder
head
and
have
it
disassembled
byan
authorized



CAUTION-

BMW
dealer
.
Be
sure
to
read
each
procedure
thoroughlybefore



Radiator
fa
n
has
left
hand
threads
.

starting
a
job
to
determinewhich
special
tools
and
equipment
will

be
necessary
.

CYLINDER
HEAD,
DISASSEMBLYANDASSEMBLY