Cylinder head BMW M3 1993 E36 User Guide

eiioo4

Fig
.
9
.



Remove
ignition
coils
on
6-cylinder
engine
by
disconnecting
harness
connector
and
removing
mounting
bolts
(arrows)
.

NOTE-

"
The
compression
gauge
reading
shoutd
increase
with
each
compression
stroke
and
reach
near
its
maxi-
mum
reading
in
about
4-6
strokes
.

"All
cylinders
shoutdreach
maximum
compression
in
the
same
number
of
strokes
.
If
a
cylinder
needs
sig-
nificantly
more
strokes
to
reach
maximum
compres-

sion,
there
is
a
problem
.

7
.
Release
the
pressure
at
the
compression
gauge
valve,

then
remove
the
gauge
from
the
spark
plughole
.
Re-

peat
the
test
for
each
of
the
other
cylinders
and
com-

pare
the
results
with
the
values
given
below
.

ENGINE-GENERAL
1
:00-
7

Compression
Pressure

"
Minimum
..........
.
.
..
..
10-11
bar
(142-156
psi)

"
Maximum
difference
between
cylinders
..
.....
.........
0
.5
bar
(7
psi)

Reinstall
the
spark
plugs
and
spark
plug
wires
or
ignition

cofs
.
The
remainder
of
installation
is
the
reverse
of
removal
.
Be
sure
to
reihstall
al¡
wires
disconnected
during
the
test,
especial-

¡y
ground
wires
at
the
coils
and
cylinder
head
cover
(where
ap-
plicable)
.

Tightening
Torque

"
Spark
plug
to
cylinder
head
.......
25
Nm
(18
ft-Ib)

Low
compression
indicates
a
poorly
sealed
combustion

6
.
With
the
parking
brake
set,
the
transmission
in
Park
or



chamber
.
Relatively
even
pressures
that
are
below
specification

Neutral,
and
the
accelerator
pedal
pressed
to
the
floor,



normally
indicate
worn
piston
rings
and/or
cylinder
walls
.
Erratic

crank
the
engine
with
the
starter
.
Record
the
highest



values
tend
to
indicate
valve
leakage
.
Dramatic
differences
be

value
indicated
by
the
gauge
.



tween
cylinders
are
often
the
sign
of
a
failed
head
gasket,

bumed
valve,
or
broken
piston
ring
.

Engine
Mechanical
Troubleshooting
Table

Table
c
lists
the
symptoms
of
common
engine
mechanical

problems,
their
probable
causes
and
the
suggested
corrective

actions
.
The
bold
type
indicates
the
repair
groups
where
appli-

cable
test
and
repair
procedures
can
befound
.

MECHANICAL
TROUBLESHOOTING

100-8
ENGINE-GENERAL

Symptom



1



Probable
cause
and
correctiveaction

1
.
Engine
will
not
start
or
run
.
Starter
cranks



a
.



No
fuel
reaching
engine
.
Check
forfuelin
tank
.

engine
at
normal
speed
.



Fuel
pump
notoperating
.
Repair
Group
160

b
.
No
spark
.
Check
ignition
system
.
Repair
Group
120

c
.
Incorrect
valve
timing
.
Check
timing
chain
.
Repair
Group
117

2
.
Check
Engine
warning
light
illuminated
.



a
.
DME
engine
management
system
self-diagnostic
fault
detected
.
Sea
an
authorized
BMW
dealer
or
other
qualified
shop
for
OBD
II
fault
code
diagnosis
.
See
also
On-
board
Diagnostics(OBD),
given
later
inthis
repair
group
.

3
.
White
exhaust
smoke
(steam)
.



a
.
Failed
cylinder
head
gasket
(probably
accompanied
bylowcompression
readings)
.

Replace
gasket
and
resurface
cylinder
head
if
necessary
.
Repair
Group
113
4
.
Blue-gray
exhaust
smoke
and
oily
spark



a
.
Contaminated
or
gasoline-diluted
engine
oil
.
Change
engine
oil
and
replace
oil
filter
.
plugs
.
Indicates
oii
burning
in
combustion
.



Repair
Group
020

b
.
Faulty
valve
guide
seals
or
valve
guides
.
Replace
valve
guide
oil
seals
or
overhaul
cylinder
head
.
Repair
Group
116

5
.
Pinging
or
rattling
when
under
load,



a
.
Ignition
timing
too
advanced
.
Ignition
knocksensors
faulty
(CheckEngine
light
traveling
uphill,
or
accelerating,
especially



illuminated)
.
Repair
Group
120fromlow
speeds
.
Indicates
pre-ignition
or



b
.
Fuel
octane
leve¡
toolow
.
detonation
.



c
.
Engine
running
too
hot
or
overheating
.
Check
cooling
system
.
Repair
Group
170

6
.
Light
metallic
tapping
that
varies
directly
with
engine
speed
.
Oil
pressure
warning
light
not
illuminated
.

7
.
Light
metallic
knock
that
varies
directly
with
enginespeed
.
Oil
pressure
warning
light
blinking
or
fully
illuminated
;
may
be
most
noticeable
during
hard
stops
or
cornering
.

8
.
Screeching
or
squealing
under
load
that



a
.
Loose,worn,
or
damaged
drive
belt
.
Inspect
belt(s)
.
Repair
Group
020
goesaway
when
coasting
.

9
.
Growling
or
rumbling
that
varieswith
engine



a
.
Remove
drive
belt(s)toidentifyfaulty
component
.
Check
for
play,
bearing
roughness,
rpm
.
Indicates
abad
bearing
or
bushing
in



and
loose
mountings
.
Refer
to
appropriate
repair
group
for
repair
procedures
.
an
engine-driven
accessory
.

DRIVEABILITY
TROUBLESHOOTING



On-Board
Diagnostics
(OBD)

On-Board
Diagnostics
is
incorporated
into
al¡
engine
man-



Two
generations
of
OBD
are
usedon
thecars
covered
by
agement
systems
used
on
the
cars
covered
by
this
manual
.



this
manual
:
Therefore,
checking
for
fault
codes
should
be
the
first
step
in
troubleshootinga
driveability
problem
.
For
additional
informa-



On-Board
Diagnostics
tion
on
engine
management
and
repair
see130
Fuel
Injec-
tion
.



"
1992-1995models
....
.
..
....
.
..
.......
OBD
I

"
1996-1998models
.
....
..
.
.
.
..
.
........
OBD
II

DRIVEABILITY
TROUBLESHOOTING

Tablec
.
Engine
Mechanical
Troubleshooting

b
.
Warped
or
cracked
cylinder
head
.
Resurface
or
replace
cylinder
head
.
Repair
Group
113

c
.
Cracked
cylinder
block
.
Replace
engine
or
short
block
.

c
.
Worn
piston
rings
.
Overhaul
or
replace
engine
.

d
.
Failed
cylinder
head
gasket
.
Replace
gasket
.
Repair
Group
113

d
.
Air/fuel
mixture
too
lean
(Check
Engine
light
illuminated)
.
Repair
Group
130

a
.
Valveclearances
excessive
.
Check
hydraulic
valve
adjusters
.
Repair
Group
116

b
.
Low
oil
pressure
orpossibly
defective
warning
light
circuit
.
Check
oil
pressure
andwarning
light
circuit
.
Repair
Group
119
c
.
Dirty
oil
.
Change
oil
.
Repair
Group
020
.

a
.
Low
oil
leve¡
.
Check
and
correct
oil
leve¡
.

b
.
Low
oil
pressure/worn
or
faulty
oil
pump
.
Oil
pump
pickup
restricted/clogged
.
Check
oil
pressure
.
Repair
Group
119

The
OBD
system
detects
emissions-related
engine
manage-
ment
malfunctions
and
tucos
on
the
Check
Engíne
lightin
the
in-
strument
cluster
.
TheCheck
Engine
light
will
stay
on
until
the
code(s)are
called
up
and
the
memory
is
erased
.
When
faulty
are
detected,
the
OBD
system
stores
a
Diagnostic
Trouble
Code
(DTC)
in
the
system
ECM
.
In
addition,
the
Check
Engine
warn-
ing
light
will
come
on
if
an
emissions-related
fault
is
detected
.

110-2



ENGINE
REMOVAL
AND
INSTALLATION

8
.
Drain
engine
coolant
andremove
coolant
hoses
at-



10
.
Remove
radiator
cooling
fan
and
radiator
as
described

tached
to
cylinder
head
.



in
170
Radiator
and
Cooling
System
.

"
Drain
radiator
and
engine
block
.
See
170
Radiator

and
Cooling
System
.



NOTE-

"
Disconnect
hoses
from
thermostat
housing
at
front
of



Some
late
4-cylinder
modelsuse
an
electric
prímary
cylinder
head
.



cooling
fan
.
"
Disconnect
heater
hoses
at
rear
of
engine
.
See
Fig
.
2
.

CAUTION-

NOTE-



On
cars
with
viscous-type
cooling
fans,
the
radia-

"
The
block
drain
plug
is
located
on
the
exhaust
side
to-



tor
fan
has
left
hand
threads
.

wards
rear
of
engine
.

"
Remove
small
plastic
lock
clíp
to
pull
radiator
drain



11
.
Remove
upper
intake
manifold,
unfasten
cable
duct

plug
out
completely
.



from
lower
intake
manifold,
crankcase
vent
valve
hose

(M44
engine
only)

0012687

Fig
.
2
.



Coolant
hoses
at
heater
valve
and
heatercore
to
be
discon-
nected
(arrows)
.

9
.
Remove
air
shroud
from
top
of
radiator
.
See
Fig
.
3
.

ENGINE
REMOVAL
AND
INSTALLATION

12
.
Disconnect
fuel
supply
and
fuel
return
lines,
main
en-

gine
electrical
connectors,
and
lower
intake
manifold
as

described
in
113
Cylinder
HeadRemoval
and
Instal-

lation
.
See
Fig
.
4
.

0012504

Fig
.
4
.



Crankcase
ventvalve
(A)
on
top
of
lower
intake
manifoldof
M44
engine
.
Fueldelivery
and
retum
lines
shown
at
B
.
Engine
harness
and
sensor
connectors
shown
at
C
.

WARNING
-

"
Fuel
may
be
expelled
under
pressure
.
Do
not
smoke
orworknear
heaters
or
other
fire
haz-
ards
.
Keep
a
fire
extinguisher
handy
.
Before
dis-
connecting
fuel
hoses,
wrap
a
cloth
around
fuel
hoses
to
absorb
any
leaking
fuel
.
Plug
all
open
fuel
lines
.

"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
in
the
tank
before
working
on
the
tank
or
lines
.

CAUTION-
0013137



I
Stuff
clean
rags
into
the
open
intake
ports
topre-
Fig
.
3
.



Front
air
shroud
mounting
screws
(arrows)
.



vent
any
parts
from
falling
into
the
engine
intake
.

13
.
Disconnect
vacuum
hose
from
brake
booster
on
bulk-
head
.
Cover
bothhole
in
booster
and
plug
hose
end
.

14
.
Unbolt
power
steering
fluid
reservoir
from
íts
mounting
bracket
.
Use
stiff
wire
to
hang
reservoir
to
one
side
.
Do
not
disconnect
fluid
lines
.

15
.
Remove
power
steering
pump
drive
belt
and
remove
pump
from
its
mounting
bracket
.
Use
stiff
wire
to
hang
pump
from
body
.

16
.
On
cars
with
automatic
transmission
remove
front
and
rear
brackets
holding
automatic
transmission
cooler
linesto
engine
.

17
.
Remove
A/C
compressor
from
its
mounting
bracket
without
disconnecting
any
refrigerantlines
.
See
Fig
.
5
.

ENGINE
REMOVAL
AND
INSTALLATION



110-
3

21
.
Remove
front
exhaust
pipefrom
exhaust
manifold
.
See

Fig
.
6
.

22
.
Install
an
engine
lifting
device
and
raise
engine
until
its

weight
is
supported
.
Remove
nuts
and
ground
strap

from
left
and
right
engine
mounts
.

0011967

Fig
.
6
.



Front
exhaustpipe
to
exhaust
mounting
nuts
(arrows),
as
viewed
from
below
on
4-cylinder
engine
.

23
.
Carefully
raíse
engine
out
of
car,
checking
for
any
wir-
ing
harnesses,
fuel
lines,
or
mechanical
parts
that
might
become
snagged
as
engine
is
removed
.

24
.
Installation
is
reverse
of
removal,
noting
the
following
:

"
Replace
all
gaskets,
O-rings
and
seals
.

"
Change
engine
oil
and
filter
and
check
al¡
other
fluid
levels
.
See020
Maintenance
Program
.
"
Refill
and
bleed
cooling
system
.
See
170
Radiator
and
Cooling
System
.

"
Insta¡¡
the
front
exhaust
pipes
using
new
gaskets
and

self-locking
nuts
.
Use
copper
pasteon
threads
.
See

180
Exhaust
System
.

Tightening
Torques

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

Fig
.
5
.
A/
C
compressor
mounting
bolts
(arrows)
.



"
Engine
mount
to
subframe

M8
......:...
..
..
..
......,:..
22
Nm
(17
ft
-
1b)
,

18
.
Move
A/C
compressor
out
of
way
without
distorting
or



M10
.
...
.



..
...
.
.
...........
45
Nm
(33
ft'-Ib)

damaging
any
lines
.
Support
compressor
by
hanging
it



"
Intake
manifold
to
cylinder
head

from
chassis
using
stiff
wire
.



M7
.....
.
..
...
..
..
...........
15
Nm
(11
ft-Ib)
M8
...
.
.
.
..
..
...
..
...........
22
Nm
(16
ft-Ib)

19
.
Disconnect
wiring
from
starter
and
alternator
.
Move



`
"
Radiator
cooling
fan
to
coolant
pump40
Nm
(30
ft-Ib)

wiring
harness
out
of
way
.
See
121
Battery,
Starter,



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

Alternator
.



"
Wiring
to
alternator
(M8
nut)
........
12
Nm
(9
ft-1b)

"
Wiring
to
starter

20
.
Remove
oil
dipstick
guide
tube
.
Note
O-ring
at
base
of



M6
nut
..
.
..
..
...
..
...........
.
:5
Nm
(44
in-lb)

tube
when
removing
.



M8
nut
..
.
..
..
...
..
............
12
Nm
(9
ft-Ib)

ENGINE
REMOVAL
AND
INSTALLATION

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
.

11
.
Draín
engine
coolant
and
Rmove
coolant
hoses
at-
tached
to
cylinder
head
.

"
Drain
engine
block
byremoving
block
drain
.
"
Disconnect
hoses
from
thermostat
housing
in
front
of
cylinder
head
.

"
Disconnect
heater
hoses
at
rear
of
engine
.
See
Fig
.
9
.
"
Drain
radiator
by
removingthreaded
plastic
plug
from
lower
left
comer
.

NOTE-

"
The
block
drain
plug
is
located
oh
the
exhaust
side
to-
wards
rear
ofengine
.

"
Remove
small
plastic
lock
clipto
pulíradiator
draín
plug
out
completely
.

NOTE-

CAUTION-

Radiatorfan
has
left
hand
threads
.

ENGINE
REMOVAL
AND
INSTALLATION



110-
5

Fig
.
9
.



Coolant
hoses
at
heater
valve
and
heater
core
to
be
discon-
nected
(arrows)
.

12
.
Remove
radiator
cooling
fan
and
radiator
as
described
in
170
Radiator
and
Cooling
System
.

13
.
Label
and
disconnectcoolant
hoses,
cables,
and
har-
ness
connectors
from
throttle
housing
.
See
Fig
.
10
.

14
.
Working
atrearof
intake
manifold,
label
and
then
re-
move
fuel
supply
and
fuel
retum
lines
.
Disconnect
fuel
lines
from
support
bracket
on
manifold
.
See
Fig
.
11
.

uu12ivu
Fig
.
10
.
Throttle
housing
assemblyon
M52
engine
.
Disconnect
hos-
es,
cables
and
harness
connectors
at
and
around
housing
.

0012699

Fig
.
11
.
Special
fuelline
fitting
at
fuel
rail
on
M52/S52US
engine
.
Use
BMW
special
tool
16
1
050
to
releaselocking
fittings
at
ends
offuel
lines
.

WARNING
-

"
Fuel
may
be
expelled
under
pressure
.
Do
not
smoke
or
work
near
heaters
or
other
fire
haz-ards
.
Keep
a
fire
extinguísher
handy
.
Before
dis-
connecting
fuel
hoses,
wrapa
cloth
around
fuel
hoses
to
absorb
any
leaking
fuel
.
Plug
all
oyen
fuel
fines
.

"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
ín
the
tank
before
working
on
the
tank
or
lines
.

OnM52
and
S52US
engines,
special
fittings
are
used
to
retain
the
fuel
lines
to
the
fuel
rail
.
Use
BMW
special



16
.
Remove
intake
manifold
from
engine
byremoving
sev-
tool
no
.
161050
to
compress
the
locking
clip
insidethe



en
mounting
nuts
from
above
andtwo
mounting
bracket
end
of
the
fuel
line
fittings
to
release
the
fine
.



boits
from
below
.
See
Fig
.
12
.

15
.
Unbolt
power
steering
fluid
reservoir
from
its
mounting



CAllTION-
bracket
.
Use
stiff
wire
to
hang
reservoir
to
one
side
.
Do



Stuff
clean
rags
into
the
open
intake
ports
to
pre-
not
disconnect
fluid
fines
.



vent
any
parts
from
falling
into
the
engine
intake
.

ENGINE
REMOVAL
AND
INSTALLATION

110-
6



ENGINE
REMOVAL
AND
INSTALLATION

Fig
.
12
.
Intake
manifold
mounting
nuts
on
6-cylinder
engine
.
Also
re-

move
two
bolts
from
support
brackets
(arrows)
.

17
.
Working
below
intake
manifold,
disconnect
harness

connectors
.
Cut
wire
ties
holding
engine
harness
to

bulkhead
and
disconnect
main
engine
harness
con-

nector
at
rear
of
engine
compartment
.
See
Fig
.
13
.

0013132

Fig
.
13
.
Main
engine
harness
connectors
in
rear
of
engine
compart-
ment
(arrow)
.

18
.
Remove
poly-ribbed
drive
belt(s)
.

19
.
Remove
engine
drive
belt
.
See
020
Maintenance
Pro-

gram
.

20
.
Remove
power
steering
pump
from
its
mounting
brack-

et
.
See
Fig
.
14
.
Use
stiff
wire
to
hang
pump
from
body
.

ENGINE
REMOVAL
AND
INSTALLATION

Fig
.
14
.
Power
steering
pump
mounting
bolts
(arrows)
.
M52
engine

shown
.

21
.
Remove
A/C
compressor
from
its
mounting
bracket

without
disconnecting
any
refrigerantlines
.
See
Fig
.

15
.

Fig
.
15
.
A/
C
compressor
mounting
bolts
(arrows)
.

22
.
Move
A/C
compressor
out
of
the
way
without
distorting



26
.
Carefully
raise
engine
out
ofcar,
checking
for
any
wir-
or
damaging
any
lines
.
Support
compressor
by
hanging



ing,fuel
lines,
or
mechanical
parts
that
might
become
it
from
chassis
using
stiff
wire
.



snagged
as
engine
is
removed
.

23
.
Disconnect
wiring
from
starter
and
alternator
.
Move



27
.
Installation
is
reverse
of
removal,
noting
the
following
:
wiring
harness
out
of
the
way
.
See
121
Battery,
Start-
Replace
al¡
gaskets,
O-rings
and
seals
.
er,
Alternator
.



"
Change
engine
oil
and
filter
and
check
all
other
fluid

24
.
Remove
Fontexhaust
pipe
fromexhaust
manifold
.
See



levels
.
See
020
Maintenance
Program
.
"
Refill
and
bleed
cooling
system
.
See
170
Radiator
Fig
.
16
.



and
Cooling
System
.

"
Check
that
engine
drivebelts
properly
engage
the
pul-

ley
grooves
.

"
Install
the
Font
exhaust
pipesusing
new
gaskets
and
seif-locking
nuts
.
Use
copper
paste
on
threads
.
See
180
Exhaust
System
.

0012525

Fig
.
16
.
Front
exhaust
pipeto
exhaust
manifolds
mounting
nuts
on
6-

cylinder
engine
(arrows)
.

25
.
Install
an
engine
lifting
device
and
raise
engine
until
its

weight
is
supported
.
Remove
nuts
and
ground
strap

from
left
and
right
engine
mounts
.

ENGINE
REMOVAL
AND
INSTALLATION



110-
7

Tightening
Torques

"
Coolant
drain
plug
to
cylinder
block
.
25
Nm
(18
ft-Ib)
"
Engine
mount
to
subframe
M10
..
.
.
.
...
..............
..
.
45
Nm
(33
ft-Ib)

M8
..
..
.
..
................
...
22
Nm
(16
ft-Ib)

"
Intake
manifold
to
cylinder
head

M7
..
..
..
...
................
.
15
Nm
(11
ft-Ib)

M8
...
.
..
...
................
.
22
Nm
(16
ft-Ib)
"
Radiator
cooling
fan
to
coolant
pump40
Nm
(30
ft-Ib)

"
Radiator
drain
screw
to
radíator
...
2
.5
Nm
(22
in-lb)
"
Wiring
to
alternator
(M8
nut)
........
12
Nm
(9
ft-Ib)

"
Wiring
to
starter

M6
nut



.
..
...
..................
5
Nm
(44
in-lb)

M8
nut
.....
..
.
.
.
.
.............
12
Nm
(9
ft-Ib)

ENGINE
REMOVAL
AND
INSTALLATION

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

113-2



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

0011s6i



-

0Fig
.
1
.



Front
exhaust
pipe
to
exhaust
manifold
mountíng
nuts
(arrows)
.
-1



~~
0013023

4
.
Remove
air
filter
housing
complete
with
mass
air
flow



Fig
.
3
.



Coolant
hose
connection
beneath
intake
manifold
on
M42

sensor
and
attached
hoses
and
ducting
.
See
Fig
.
2
.



engine
(arrow)
.

0011969

Fig
.
2
.



Air
filter
housing/air
intake
connections
on
M44
engine
with
traction
control
.
Clamp
atthrottle
housing
(A)
;
mass
air
flow
sensor
connector
(B)
;
and
clips
at
upper
air
filter
housing
(C)
.

Coolingsystem,
draining

5
.
Draincoolant
from
engine
block
and
radiator
.
See
170

Radiator
and
Cooling
System
.

NOTE-

"
The
block
drain
is
on
the
exhaust
sideof
the
engine,
near
cylinder
no
.
4
.

6
.
Disconnect
hoses
from
coolant
flange/thermostat
hous-
ing
on
frontof
cylinder
head
.
Unbolt
thermostat
housing
from
cylinder
head
.

CYLINDER
HEAD,
4-CYLINDER

7
.
On
M42
engines,
disconnect
hose
from
coolant
pipe
on

left
side
of
engine
.
See
Fig
.
3
.

8
.
Disconnect
heater
hoses
from
coolant
flange
on
rear
of
cylinder
head
.

Cylinder
head
cover,
removing

9
.
Remove
ignition
coil
pack
from
rightstrut
tower
.
See

Fig
.
4
.

0011995
"
The
radiator
drain
plug
is
on
the
bottomof
the
radiator



Fig
.
4
.



Cylinder
head
cover
showing
location
of
engine
breather
hose
on
the
driver's
side
.
Remove
small
plastic
lock
clipto



(A),
wiring
harness
duct
(B),
and
ignition
coil
pack
(C)
.
M44
pull
radiator
drain
plug
out
completely
.



engine
shown
.
Cover
on
M42
engine
is
similar
.

10
.
Disconnect
engine
breather
hose
from
cylinder
head
cover
.