engine mount BMW 328i 1997 E36 Owner's Manual

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
.

11
.
Detach
wiring
harness
duct
at
rear
bulkhead
panel
and
pull
complete
duct
forward
and
up
to
allow
access
to
rear
of
cylinder
head
cover
.

12
.
Remove
spark
plugs
and
spark
plugwire
loom
.

"
Remove
plastic
cover
from
top
of
cylinder
head
.

"
Disconnect
spark
plug
wires
fromspark
plugs
and
re-

move
spark
plugs
.
"
Unbolt
spark
plug
cable
harness
and
heat
shield
from
right
side
of
cylinder
head
cover
and
set
aside
.

13
.
Unscrew
andremove
cylinder
head
cover
cap
screws

and
remove
cover
.
See
Fig
.
5
.

CAUTION-

Two
of
the
cover
hold-down
screws
are
under
the
spark
plug
cable
duct
.

NOTE-

Make
note
of
the
arrangement
of
cap
screws,
washers
and
rubber
grommets
holding
the
cylinder
head
cover
in
place
.

Fig
.
5
.



Cylinder
head
cover
mounting
points
(arrows)
.

Fig
.
7
.



M44
fuel
rail
air
connection
(A)
and
fuel
supply
and
return
lines
Intake
manifold,
removing



(B)
.

14
.
On
late
engines,
disconnect
injector
air
shrouding
hose

from
fitting
at
center
of
upper
intake
manifold
.



18
.
Disconnect
fuel
supply
and
return
lines
from
fuel
rail
.

15
.
Remove
upper
section
of
intake
manifold
.

"
Disconnect
ali
cables
harness
connectors
from
throttle

housing
and
intake
manifold
.

"
Disconnect
fuel
tank
vent
hose
fromvent
valve
on
low-

er
sitie
of
manifold
.

"
Remove
manifold
support
brackets
.
See
Fig
.
6
.

"
Remove
upper-to-lower
manifold
fasteners
(1
bolt,
2

nuts)
and
separate
upper
manifold
from
lowermani-

fold
.

Note
locating
dowei
sleeves
on
lower
to
upper
manifold
mounting
studs
.
Remove
dowels
and
set
aside
.
See
Fig
.
8
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-3

0012686

Fig
.
6
.



Intake
manifold
support
brackets
and
mountinghardware
.
Manifold
for
M44
engine
shows
.

16
.
Disconnect
oil
dipstick
tube
bracket
from
lower
manifold
section
.

17
.
On
M44
engine,
relieve
fuel
pressure
using
com-

pressed
air
(maximum
3
bar
pressure)
at
schroeder

valve
on
fuel
rail
.
Briefly
apply
air
pressure
to
force
fuel

back
intofuel
tank
.
See
Fig
.
7
.

WARNING
-

"
The
fuel
system
retains
fuel
pressure
when
the
engine
is
off
(up
to
75
psi)
.
Use
care
when
dis-
connecting
fuel
lines
.
Unscrew
the
fuel
tank
cap
to
retease
pressure
in
the
tank
.
Wrap
a
clean
shop
towel
around
the
fitting
when
loosening
.

"
Fuel
is
highly
flammable
.
When
working
around
fuel,
do
not
disconnect
any
wires
that
could
cause
electrical
sparks
.
Do
not
smoke
or
worknear
heaters
or
other
tire
hazards
.
Placea
tire
extin-
guisher
in
the
vicinity
of
the
work
area
.

19
.
Disconnect
coolant
hoses
from
vent
valve
on
lower
intake

manifold
.
Remove
crankcase
vent
valve
from
manifold
.

CYLINDER
HEAD,
4-CYLINDER

113-4



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

20
.
Disconnect
main
engine
wiring
harness
connector
.
La-

bel
and
disconnect
harness
connectors
for
crankshaft

and
camshaft
sensors
.
See
Fig
.
8
.

0012504

Fig
..
Crankcase
vent
valve
(A),
camshaft
and
crankshaft
sensor
harness
connectors
(B),
locating
bushings
(C),
main
engine
wiring
harnessconnector
(D)
.
M44
engine
shown
.

NOTE-

Early
engines
do
not
havea
maín
disconnect
at
the
lower
intake
manifold
harness
.
lf
necessary,
remove
the
cable
ducting
bolts
and
set
harness
ducting
aside
.

21
.
Remové
lower
section
of
intake
manifold
.

"
Remove
Y
shaped
supportbracket
from
underside
of
manifold
.
(See
Fig
.
6
.)
"
Unbolt
support
brackets
from
alternator
and
starter
.
"
Remove
nuts
holding
manifold
to
cylinder
head
and
pull
manifold
back
until
harness
connectors
for
oil

pressure
switch
and
coolant
temperature
sensorare

accessible
.
Label
and
disconnect
connectors,
then
re-

move
manifold
and
set
aside
.

Timing
chains,
uncoupling



26
.
Lock
crankshaft
in
TDC
position
by
insertíng
BMW
spe-

22
.
On
M42
engines,
remove
thermostat
housing
from
up-



cial
tool
no
.
11
2
300
through
bore
and
into
hole
infly-

per
timing
chaincover
.



wheel
or
driveplate
.
See
Fig
.
11
.

23
.
On
late
M44
engines
(January
1997
and
later),
remove



NOTE-
secondary
air
injection
check-valve
from
front
of
engine



"
If
necessary,
remove
plug
from
locating
bore
in
lower
and
lay
aside
.



edge
of
bell
housing
to
insert
locking
tool
.

24
.
Remove
cylinder
identification
sensor
from
upper
tim-
ing
chaincover
.
Remove
upper
timing
chaincover
.
See
Fig
.
9
.

25
.
Set
engine
to
approximate
TDC
by
rotating
in
normal
operating
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
.
See
Fig
.
10
.

CYLINDER
HEAD,
4-CYLINDER

Fig
.
9
.



Upper
timing
chain
cover
bolts
(arrows)
.
Remove
secondary
air
injection
check
valve
fromhose
(A)
on
M44
engine
.
Re-
move
cylinder
identification
sensor
from
chaincover
(B)
.

0011998

Fig
.
10
.
Engine
set
to
approximate
TDC
.
Cylinder
no
.
1
camshaft
lobes
face
in
and
arrows
on
sprockets
poínt
up
(arrows)
.

"
Confirm
that
the
locking
tool
has
been
correctly
in-
stalled
by
trying
to
rotate
the
crankshaft
.

27
.
Lock
camshafts
at
TDC
by
mounting
BMW
specíal
tool
no
.
113
240
over
square
ends
of
camshafts
.
See
Fig
.
12
.

NOTE-

Check
that
tool
is
squarely
seated
on
cylinder
head
gasket
surface
.
If
necessary,
rotate
camshafts
slightly
using
an
open-end
wrench
at
hex
oncamshafts
.

Fig
.
11
.
BMW
special
tool
no
.
11
2300
installed
through
bellhousin
and
finto
flywheel
(arrow)
tolockcrankshaft
at
TDC
.

Fig
.
12
.
BMW
special
tool
no
.
11
3
240
installed
on
rear
of
camshafts
tohold
them
at
TDC
.
(M44
engine
shown
.
Other
engínes
are

similar
.)

CAUTION-

The
camshafts
must
be
locked
in
the
TDC
position

using
the
special
service
tool,
or
equivalent,
be-

fore
removing
the
timing
chaín
.
The
tool
holds
the
camshafts
parallel
to
each
other
and
perpendicu-
larto
the
valve
covergasket
surface
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-5

6011966

28
.
Remove
hydraulic
chain
tensiones
from
right
side
ofcyl-

inder
head
.
See
Fig
.
13
.

Fig
.
13
.
Hydraulic
chain
tensioner
(arrow)
.

NOTE-

It
is
not
necessary
to
remove
the
cam
sprockets
from

the
chainuntessthese
parts
are
being
reptaced
.
tire
tie
each
sprocket
to
the
chain
to
keep
the
sprockets
timed
to
each
other
.
Keeping
the
sprockets
timed
will
símplífy
instaftation
.

uu
11999

Fig
.
14
.
Chainguide
and
guide
adjusting
sleeve
(arrow)
.
Allen-head
retaining
screwhasbeen
removed
.
Use
slotted
screwdriver
to
loosen
adjusting
sleeve
.

29
.
Remove
mounting
bolts
from
left
and
right
camshaft

sprockets
.
Then
remove
camshaft
sprockets
from
cam-



_



Cylinder
head
assembly,
removing

shafts
.
On
M44
engines,
note
orientation
of
sensor



31
.
Remove
crankshaft
locking
tool
(BMW
special
tool
no
.
wheel
.



11
2
300)
.
Usingthe
crankshaft
vibration
damper
bolt,

30
.
Remove
upper
bolt
from
left
chainguide
.
Loosen
chain



turn
engine
opposite
its
normal
direction
of
rotation

guide
adjusting
sleeve
approximately
two
turns
.
See



(counterclockwise
asviewed
from
the
front)
approxi

Fig
.
14
.



mately
45°
.
This
prevents
accidental
contact
between

valves
and
pistons
during
installation
.

CYLINDER
HEAD,
4-CYLINDER

113-8



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

IW?
-
L
'/~f
W



~
4r

"

-
"



;,s
1

12
.
On
M44
engine
:
Place
sensor
wheel
on
intake
cam-
shaft
sprocket
so
that
arrowon
sensor
wheel
points
up
.

13
.
Instan
and
hand-tighten
sprocket
mounting
bolts
.

CAUTION-

Different
hydraulic
chaintensioners
were
used
during
manufacture,
depending
onengine
type
.
See
Fig
.
21
.
Note
that
the
late
style
tensioner
can
be
retrofitted
to
the
earlier
engine,
so
be
sure
to
identify
the
version
of
tensioner
installed
as
insta-lation
instructions
vary
between
the
two
.

14
.
On
M42
engine
:
Disassemble
chain
tensioner
by
strik-
ing
outer
sleeve
against
a
solid
object
.
This
will
release
snap
ring
and
tensioner
will
separate
.
See
Fig
.
22
.

M42
Engine

up
and
camshaft
threaded
holes
centered
in
siotted
holes
.

CYLINDER
HEAD,
4-CYLINDER

0013024a

Outer
sl
eve



Detent

ring

Spri
g

Fig
.
22
.
Disassembled
chain
tensioner
for
M42
engine
.

15
.
On
M42
engine
:
Clamp
tensioner
piston
in
vice
(soft

jaws)
.
Slowly
compress
piston,
making
sure
detent
ring

fits
into
taper
of
outer
sleeve
.
If
necessary,
press
ends

of
detent
ring
together
.
Slowly
continuepressing
ten-

sioner
together
until
snap
ring
audibly
clicksinto
outer

sleeve
.
Measure
overall
lengthof
tensioner
to
confirm

correct
assembly
:
68
.5
mm
(2.7
in
.)
.

NOTE-

i

Snap

ring

/0
.13024

The
late-style
tensioner
on
the
M44
engíne
canbe
ret-
rofitted
to
the
M42
engine
.

Tightening
Torque

"Chain
tensioner
plug
to
cylinder
head
.....
.-~
..........
40
Nm
(30
ft-Ib)

16
.
On
M44
engíne
:
Clamp
tensioner
píston
in
vice
(soft

jaws)
and
squeeze
oil
from
it
.
Slowly
compress
piston
only
up
to
end
circlip
.
Repeat
procedure
twice
to
ensure

all
oil
is
expelled
.
See
Fig
.
23
.

17
.
Instan
hydraulic
chain
tensioner
to
cylinder
head
.
Use
a
new
sealing
washer
on
tensioner
when
installing
.

18
.
On
M42
engine
:
Unlock
chain
tensioner
by
pressing
chain
rail
against
tensioner
until
it
expands
out
.

19
.
Check
that
chain
is
free
of
slack
.
Tighten
sprocket
mounting
bolts
.
Fig
.
21
.
Two
versions
of
hydraulic
chain
tensioners
.
Original
chainten-
sioner
on
M42
engine
(top)
can
be
disassembled
.
Chain
ten
sioner
on
M44
engine
(bottom)
cannotbe
disassembled
.



Tightening
Torque
Note
differences
in
outer
sleeve
.
Also,
the
M42
tensioner
de-



"
Chain
sprocket
to
camshaft
flange
.
..
10
Nm
(89
in-lb)
tent
ring
groove
(arrow)
is
visible
when
tensioner
is
extended
.

20
.
Remove
crankshaft
locking
tool
from
bellhousing
and
camshaft
locking
tool
from
rear
of
cylinder
head
.

Fig
.
23
.
When
reinstalling
chain
tensioner
on
M44
engine,
old
oil
in
tensioner
piston
mustbe
expelled
bycompressing
piston
in
vise
.
When
compressing
piston,
only
compress
up
to
end
cir-
clip
(arrow)
.

21
.
Turn
engine
overby
hand
in
direction
of
rotation
at
least

two
fui¡
rotations
.
Reinstall
camshaft
and
crankshaft

locking
tools
to
check
engíne
timing
.
Remove
locking

tools
if
no
faults
are
found
.

22
.
Insta¡¡
upper
timingchain
cover
.

"
Install
gaskets
and
instan
cover
using
two
mounting



Tightening
Torque

bolts
.
Using
a
screwdriver,
lever
down
on
front
cover



"
Cylinder
head
cover
until
cover
gasket
surface
is
flush
with
cylinder
head



to
cylinder
head
(M6
screws)
.......
10
Nm
(89
in-lb)

gasket
surface
.
See
Fig
.
24
.
Tighten
two
bolis
.

"
Insta¡¡
and
tighten
remainder
of
bolis
.

23
.
Install
cylinder
head
cover
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-
9

0012507

Fig
.
24
.
Install
upper
timing
case
cover
with
two
bolis,
then
press

down
on
cover
so
that
top
surface
is
flush
withcylinder
head
(arrow)
.
Hold
cover
in
position
and
tighten
bolis
.

"
Clean
old
gasket
glue
from
sealing
surfaces
.
Usea

small
amount
of
3-Bond
®
1209
adhesive
or
equivalent

at
corners
of
half-moon
cut-outs
at
back
of
cylinder

head
.
See
Fig
.
25
.

NOTE-

OnM44
engines,
reptace
sea¡
for
oil
supply
tube
.
See
Fig
.
17
.)

Fig
.
25
.
Rear
of
cylinder
head
cover
showing
area
where
sealant
(ar-
rows)
should
be
applied
.
Inset
shows
cylinder
head
cover
mounting
bolt
and
insulator
assembly
:
M6
screw
(1),
rubber
damper
(2),
washer
(3)
.

24
.
Installation
of
remaining
parts
is
reverseofremoval,

noting
the
following
:

"
Make
sure
al¡
sealing
surfaces
are
clean
and
free
of
old

gasket
material
.
Install
new
intake
manifold
gasket
.

"
On
M44
engine
:
Replace
seals
above
and
below

crankcase
ventvalve
.

"
When
installing
lower
intake
manifold,
make
sure
hol-

low
locating
bushings
are
on
two
lower
studs
.

"
Reinstall
harness
connectors
for
oil
pressure
switch

and
coolant
temperature
sensor
before
installing
in-

take
manifold
.
Tighten
manifold
nuts
in
stages
.

"
Refill
cooling
system
as
described
in
170
Radiator

and
Cooling
System
.

"
Change
engine
oil
and
filter
as
described
in
020
Main-

tenance
Program
.

"
If
necessary,
adjust
accelerator
cable
.

"
Run
engine
at
approx
.
3,500
rpm
for
about
20
seconds

to
allow
hydraulic
chain
tensioner
to
fill
with
oil
.

"
Reconnect
battery
last
.

CYLINDER
HEAD,-CYLINDER

Fig
.
27
.
Remove
top
enginecovers
by
prying
out
plugs
and
removing

nuts
(A)
.
Make
sure
rubber
insulators
on
either
side
of
large

cover
do
not
fall
off
during
cover
removal
(B)
.

Fig
.
28
.
Fuel
injection
harness
beíng
lifted
off
engine
to
be
placed
at

base
of
windshield
(A)
.
Ignitioncoils
are
also
visible
(B)
.
M50

engine
shown,
other
6-cylinder
engines
are
similar
.

14
.
Remove
cylinder
head
cover
mounting
bolts
and
re-

move
cylinder
head
cover
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-
11

15
.
Remove
oil
baffle
cover
from
above
intake
camshaft
.

See
Fig
.
29
.

Fig
.
29
.
Camshaft
oil
baffle
coverbeing
removed
.

NOTE-

The
cylinder
head
cover
mounting
bolt
insulators
and

13
.
Remove
hold
down
nuts/bolts
from
fuel
injection
har-



gaskets
should
be
reinstalled
in
the
same
order
.
Make

ness
.
Pry
back
injector
connector
retaining
clips
and
lift



note
of
their
arrangement
during
removal
.

entire
harness
off
engine
.
See
Fig
.
28
.

Intake
manifold,
removing

811119

16
.
Disconnect
vacuum
hose
from
brake
system
vacuum

booster
.
Plug
opening
in
booster
.

17
.
Remove
throttle
housing
mounting
bolts
and
remove

throttle
housing
.
Set
throttle
housing
aside
without
dis-

connecting
cablesor
coolant
hoses
.
See
Fig
.
30
.

Fig
.
30
.
Remove
4
comer
bolts
(arrows)
from
throttle
housing
and

unbolt
complete
assembly
from
intake
manifold
.
Remove

complete
throttle
assembly
without
disconnecting
connec-

tors,
hoses
or
cables
.
(M50
engine
shown
.)

CYLINDER
HEAD,
6-CYLINDER

113-12



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION

18
.
Working
from
underside
of
intake
manifold,
disconnect



21
.
Detach
oil
dipstick
guide
tube
from
manifold
.
Disconharness
connectors,
vent
hoses,
and
air
bypass



nectvent
hose
at
base
of
dipstick
.
hoses)
.

22
.
Remove
intake
manifold
from
engine
byremoving
sev-19
.
Working
at
rear
of
intake
manifold,
label
and
disconnect



en
mounting
nuts
from
above
andtwo
support
bracket
fuel
supply
and
fuel
return
lines
.
Remove
fuelline
hold



bolts
from
below
.
See
Fig
.
32
.
down
bracket
to
free
lines
.
See
Fig
.
31
.

NOTE-

On
M52IS52US
engines,
a
special
fitting
is
used
to
re-tain
the
fuel
fines
to
the
fuel
rail
.
Use
BMW
special
tool
no
.
16
1
050
to
expand
the
locking
clip
inside
the
end
of
the
fuellíne
fittings
.

WARNING
-

"
The
fuel
system
is
desígned
to
retan
pressure
even
wheh
the
ignition
is
off
.
When
working
with
the
fuel
system,
loosen
the
fuel
lines
slowly
toal-
low
residual
fuel
pressure
to
dissipate
gradually
.
Avoid
spraying
fuel
.

"
Fuel
is
highly
flammable
.
When
working
around
fuel,
do
not
disconnect
any
wires
that
could
cause
electrfcal
sparks
.
Do
not
smoke
orwork
near
heaters
or
other
fire
hazards
.

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

20
.
Remove
mountingscrews
and
release
wiring
harness
duct
at
rear
bulkhead
and
move
aside
.
Remove
wiring
harness
brackets
frombulkhead
.

CYLINDER
HEAD,
6-CYLINDER

Fig
.
32
.
Intake
manifoldnuts
and
support
bracket
bolts
(arrows)
.

CAUTION-

Stuff
clean
rags
into
the
open
intake
ports
topre-
001269s



vent
any
ports
from
falfing
into
the
engine
.
Fig
.
31
.
Fuel
lines
at
intake
manifold
on
M52/S52
engine
.
Use
BMW
special
tool
16
1
050
to
release
locking
fittings
at
ends
of
fuel
enes
.



1



Timing
chains,
uncoupling

23
.
Remove
VANOS
unit
from
frontof
cylinder
head
.
See
VANOS
section
in
117
Camshaft
Timing
Chain
.

24
.
Setengine
to
approximate
TDC
by
rotating
in
normal
operating
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
.
Arrows
on
camshaft
sprockets
should
be
pointing
up
.

NOTE-

To
confirm
that
the
crankshaft
is
set
to
the
TDC
posi-
tion,
check
that
the
OIT
mark
(0°
TDC)on
the
front
low-
er
timing
chain
cover
ís
aligned
with
the
víbration
damperSee
Fig
.
33
.

25
.
Lock
crankshaft
at
TDC
.

"
Insert
BMW
special
tool
no
.
11
2
300
through
transmis-
sion
bellhousing
and
finto
hole
in
flywheelor
drive
plate
.
See
Fig
.
34
.

Fig
.
33
.
Crankshaft
is
positioned
at
TDC
when
notch
oh
front
timing
chain
cover
is
alignedwith
0/T
mark
on
víbration
damper
.

CYLINDER
HEAD
REMOVAL
AND
INSTALLATION



113-
1
3

Fig
.
35
.
Camshaft
locking
tool
(BMW
special
tool
no
.
11
3
240)
in-
stalled
on
rear
of
camshafts
.
(M44
engine
shown
.
Other
en-
gines
are
similar
.)

CAUTION-

The
camshafts
must
be
locked
in
the
TDC
position
using
the
special
service
tool
before
removing
the
timing
chain
.
Thearrowson
the
sprockets
should
not
be
used
to
accurately
set
the
engine
to
TDC
.
The
tool
holds
the
camshafts
parallel
to
each
oth-
er
and
perpendicular
to
the
cylinder
head
covergasket
surface
.

27
.
Depress
secondary
timing
chain
tensioner
and
lock
t

down
by
inserting
BMW
special
tool
no
.
113
292
.
Alter-

natively,
a
stiff
piece
of
wire
can
be
used
.
See
Fig
.,36
.

Fig
.
34
.
Crankshaft
locking
tool
(BMW
special
tool
11
2
300)
inserted



Fig
.
36
.
Press
secondary
tensioner
down
fully
and
insert
wire
through
through
bellhousinghole
and
finto
flywheel
(arrow)
.



holes
(arrow)
to
lock
.
Timingchain
tensioner
varies
depend-
ing
on
engine
(M52
engine
tensioner
shown)
.

26
.
Lockcamshafts
at
TDC
.

"
Remove
three
cylinder
head
cover
mounting
studs



28
.
Remove
mounting
nuts
from
front
of
intake
camshaft

from
across
rear
of
head,
if
applicable
.



sprocket
.
Remove
camshaft
sprocket,
thrust
washer(s),

"
Mount
BMW
special
tool
no
.
11
3
240
over
square



and
where
applicable,
spring
plate
.

ends
of
camshafts
.
Check
that
tool
is
squarely
seated

on
cylinder
head
gasket
surface
.
If
necessary,
rotate



NOTE-

camshafts
slightly
using
a
24
mm
wrench
at
hexon



Where
applicable,
make
note
of
thrust
washer
positions
.

camshaft(s)
.
See
Fig
.
35
.



The
thicker
(0
.4
mm)
washer
is
mounted
outermost
.

CYLINDER
HEAD,6-CYLINDER

113-14



CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
29
.
Remove
mounting
nuts
from
front
of
exhaustcamshaft

sprocket
.
Remove
secondary
sprockets
together
with

timing
chain
from
front
of
camshafts
.

CAUTION-

The
crankshaft
must
not
be
allowed
to
rotate
once
the
camshaft
timing
chain
is
removed
.
The
pistons
can
contact
thevalves
.

NOTE-

Do
not
remove
the
sprockets
from
the
chain
unless
these
parts
are
being
replaced
.
Wire
tie
each
sprocket
to
the
chain
to
keep
the
sprockets
timed
to
each
other
.

30
.
Unbolt
secondary
timing
chain
tensioner
from
top
of

cylinder
head
.

31
.
Remove
primary
timing
chaintensioner
from
side
of

cylinder
head
.
See
Fig
.
37
.

Fig
.
37
.
Primary
timing
chain
tensioner
(arrow)
.

WARNING
-

Remove
tensioner
slowly-¡t
ís
under
spring
pres-
sure
.

32
.
Remove
timing
chainguíde
(Tono
E8
socket)
.
See
Fig
.
38
.

33
.
Lift
primary
chain
sprocket
off
exhaust
camshaft
.
Re-
move
sprocket
from
chain
.
Suspend
chainusing
stiff
wire
.

Cylinder
head
assembly,
removing

34
.
Remove
two
mounting
bolts
holding
cylinder
head
to
lower
timing
chaincover
(Torx
E8
socket)
.
See
Fig
.
39
.

CYLINDER
HEAD,
6-CYLINDER

Fig
.
38
.
Timing
chain
guide
mounting
bolts
(arrows)
.
M50
engine
shown
.

Fig
.
39
.
Cylinder
head-to-timing
chain
covermounting
boits(arrows)
.
(Bolt
A
also
retains
secondary
chain
tensioner
.)

35
.
Using
BMMI
special
tool
no
.
11
2
250
or
an
equivalent

tool,
loosen
cylinder
head
bolts
in
several
stages
.
See
Fig
.
40
.
Discard
head
boits
.

CAUTION-

Torx-type
cylinder
head
bolts
should
not
be
re-
used
.
Theyare
stretch-type
bolts
and
must
atwaysbe
replaced
whenever
loosened
.