Solt
Diameter
and
Wrench
Size
"
M5
.
...
............
....
......
.
.......
8
mm
"
M6
.
.
..............
.
.
...
...........
.10
mm
"
M8
.
.
..............
.
.
..
.....
12mmor13mm
"
M10
..
.............
.
.
...
...........
.17
mm
"
M12
...
...........
..
.
..
............
.19
mm
"
M14
.
..:
.
.........
..
.
..
.............
22
mm
Spark
Plug
Socket
.
A
special
socket
for
spark
plugs
is
the
correct
size,
is
deep
enough
to
accommodate
a
spark
plug's
length,
and
includes
a
rubber
insertto
both
protect
the
spark
plug
from
damage
and
grip
it
for
easier
removal
.
See
Fig
.
9
.
Fig
.
9
.
Spark
plug
socket
.
FUNDAMENTALS
FOR
THEDO-ITYOURSELF
OWNER
010-
9
B003FNG
Pliers
.
A
few
of
the
many
types
ofpliers
are
shown
in
Fig
.
10
.
Mostare
used
for
holding
irregularobjects,
bending,or
crimp-
ing
.
Some
have
special
applications
.
A
needlenose
plier
is
used
for
gripping
small
and
poorly
ac-
cessible
objects,
and
is
useful
for
wiring
and
other
electrical
work
.
A
locking
plier
suchas
theVise-Grip
®
is
useful
because
of
its
tightgrip
.
Snap-ring
and
circlip
pliers
withspecial
tipped
jacas
areused
lo
remove
and
install
snap-ringsor
circlips
.
A
Channel-lock®
or
water
pump
plier
has
adjustable
jacas
that
can
be
quickly
changed
to
match
the
size
of
the
object
being
held
to
give
great-
erleverage
.
An
adjustable
wrench
canbea
useful
addition
to
a
small
tool
kit
.
See
Fig
.
11
.
It
can
substitute
in
a
pinch,
if
two
wrenches
of
the
same
size
are
needed
lo
remove
a
nut
and
bolt
.
Use
extra
care
with
adjustable
wrenches,
as
they
tend
to
loosen,
slip,
and
damage
fasteners
.
Fig
.
11
.
Adjustable
wrench
.
B008FNG
Compared
to
a
wrench
of
the
correct
size,
an
adjustable
wrench
is
always
second
best
.
They
shouldonly
beused
when
the
correct
size
wrench
is
not
available
.
Choose
one
of
average
size
range,
about
6
to
8
inches
in
length
.
Jack
Stands
Strong
jack
stands
are
extremely
important
for
any
work
that
is
done
under
thecar
.
Use
onlyjack
stands
that
are
designed
for
the
purpose
.
Blocks
of
wood,
concrete,
bricks,
etc
.
arenot
safeor
suitable
substitutes
.
WARNING
-
A
jack
should
be
used
only
to
raise
the
vehicle
and
shouldnot
beused
to
support
the
car
for
a
long
pe-
riod
.
Always
use
jack
stands
to
support
a
raised
ve-
hicle
.
Jack
standsare
available
1n
severa¡
styles
.
A
typical
jack
stand
is
shown
in
Fig
.
12
.
The
best
ones
are
made
of
heavy
ma-
terial
for
strength,
have
a
wide
base
for
stability,
and
are
equipped
lo
positively
lock
in
their
raised
positions
.
Get
the
best
ones
available
.
Oil
Change
Equipment
Changing
engine
oil
requires
a
17mm
socket
or
wrench
to
BOO6FNG-
loosen
and
tighten
the
drain
plug
and
a
drain
pan
(at
least
8
qt
.
capacity)
.
An
oil
filter
wrench
is
not
required
.
These
items
are
Fig
.
10
.
Pliers
.
From
left,
snap-ring,
needlenose,
adjustable-joint
shown
in
Fig
.
13
.
A
wide,
loca
drain
pan
wíll
fit
more
easily
under
(Channellock©),
slip-joint,
and
locking(Vise-Grip®)
.
the
car
.
Use
a
funnel
lo
pour
the
new
oil
into
theengine
.
TOOLS
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
.
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-
6
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
32
.
Using
Torx
E12
socket,
remove
cylinder
head
bolts
in
2
.
Check
gasket
surface
of
cylinder
head
and
cylinder
the
sequence
indicated
.
See
Fig
.
15
.
Remove
cylinder
block
for
warpage
using
a
straight
edge
.
head
and
head
gasket
.
Discard
head
boits
.
3
.
On
M42
engine
:
Be
sure
oil
feed
check
valve
and
spac-
er
are
correctly
positioned
in
block
.
See
Fig
.
16
.
0012502
Fig
.
15
.
Cylinder
head
bolt
loosening
sequence
.
Use
Torx
El
2
socket
.
Cylinder
head,
installing
(4-cylinder
engine)
CAUTION-
If
the
camshafts
were
removedrínstalled
while
the
cylinder
head
was
off,
a
minimum
wafting
time
ís
requíred
after
installing
the
camshafts
.
When
the
camshafts
are
removed,
the
hydraulic
lifters
canexpand
.
This
expansion
can
cause
fncreased
valve
lift,
resultíng
in
open
valves
and
pfston
con-
tact
Cylinder
head
installation
waiting
times
"
Ator
above
68°F
(20°C)
...............
10
minutes
"50-68°F
(10-20°C)
.
.
..
...............
30
minutes
"
32-50°F
(0-10°C)
..
.
..
...............
75
minutes
1
.
Clean
cylinder
head
and
gasket
surfaces
of
cylinder
block
and
al¡
timing
chain
covers
.
"
Remove
al¡
foreign
matter
and
any
¡¡quid
from
bolt
holes,
then
clean
with
a
thread
chaser
.
CAUTION-
Do
not
useametal
scraper
or
wire
brush
to
clean
the
alumfnum
cylinder
head
or
pistons
.
If
neces-
sary,
useahard
wooden
or
plastic
scraper
.
Also
available
are
abrasivediscs
to
be
used
ín
conjunc-
tionwíth
an
electric
dril¡
.
Be
sure
to
use
the
correct
disc
for
the
type
of
metalbeingcleaned
.
CYLINDER
HEAD,
4-CYLINDER
Fig
.
16
.
Oil
feed
check
valve
and
spacer
used
on
M42
engine
.
Install
check
valvewíth
collar
(arrow)
facing
down
.
CAUTION-
If
the
check
valve
is
not
installed
correctly,
oil
flow
to
the
cylinder
head
would
be
restrícted
.
4
.
Place
new
cylinder
head
gasket
on
surface
of
cylinder
block
.
Check
that
two
locating
dowels
are
correctly
po-
sitioned
in
block
and
not
damaged
.
CAUTION-
The
word
"OBEN",
prfnted
on
the
gasket,
should
face
up
.
5
.
Place
new
rubber
profile
gasket
in
groove
of
front
cover
.
6
.
With
camshafts
locked
in
TDC
positionwith
BMW
spe-
cial
tool
as
described
earlier,
set
cylinder
head
in
posi-
tion
.
CAUTION-
"
The
camshafts
mustbe
focked
in
the
TDC
posi-
tion
at
the
rear
of
the
cylinder
head
with
BMW
specfal
tool
no
.
113240
before
installing
the
cyl-
inder
head
.
"
Make
sure
the
crankshaft,
which
had
been
rotat-
ed
approximately
45°
opposite
the
dfrection
of
engine
rotation,
is
still
in
thatposition
before
low-
ering
the
cyffnder
head
ínto
position
.
"
Torx-type
cylinder
head
bolts
should
not
be
re-
used
.
They
are
stretch-type
bolts
and
must
al-
waysbe
replaced
whenever
loosened
.
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
.
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
.
117-
6
CAMSHAFT
TIMING
CHAIN
15
.
Insta¡¡
upper
timing
chaincover
:
17
.
Remove
crankshaft
locking
tool
from
transmission
bell-
"
Thoroughly
clean
profile
gasketgroove
and
all
sealing
housing
and
camshaft
locking
tool
from
rear
of
cylinder
surfaces
.
head
.
"
Applya
small
bead
ofsilicon
sealer
(3-Bond
1209®
or
equivalent)
to
upper
and
lower
joint
comers
where
18
.
Turn
engine
over
by
hand
in
direction
of
rotation
at
least
chaincover
meets
cylinder
head
.
two
full
rotations
.
Reinstall
camshaft
and
crankshaft
"
Insta¡¡
new
profile
gasket
to
groove
in
lowerchain
cover
.
locking
tools
to
check
engine
timing
.
Repeat
cam
timing
"
Protect
top
of
profile
gasket
using
thin
sheetmetal
procedure
if
tools
do
not
fit
easily
into
position
.
Remove
(BMW
special
tool
no
.
11
2
330
or
equivalent)
.
See
locking
tools
.
Fig
.
15
.
"
Attach
new
gaskets
to
cover
with
light
dabs
of
gasket
19
.
Install
cylinder
head
cover
as
described
in
113
Cylin-
sealant,
hold
gaskets
in
placeusing
cover
mounting
der
HeadRemoval
and
Installation
.
screws
.
"
Place
upper
timing
cover
into
position
.
Snug
down
al¡
NOTE-
screws,
without
tightening
.
Carefully
slide
out
sheet
OnM44
engines,
note
oil
supply
O-ring
and
replace
ff
metal
.
necessary
.
"
Temporarily
install
cylinder
head
cover
without
gasket
.
Insta¡¡
and
tighten
at
least
two
cylinder
head
cover
mounting
bolts
to
seat
upper
timing
chaincover
.
"
Tighten
all
upper
timing
cover
screws
.
Tightening
Torque
"
Remove
valve
cover
.
"
Cylinder
head
cover
to
cylinder
head
(M6
screws)
...
..
.
.
10
Nm
(89
ín-Ib)
-
CAMSHAFT
TIMING
CHAINS,
Fig
.
15
.
When
installing
upper
timing
chain
cover,
use
thin
sheetmetal
6-CYLINDER
(arrow)
to
protect
profile
gasket
when
installing
uppercover
.
Tightening
Torque
"
Upper
timing
chaincover
to
engine
block
or
cylinder
head
(M6
screws)
....
.
..
10
Nm
(89
in-lb)
16
.
Install
vibration
damper
while
aligning
woodruff
key
.
Hold
crankshaft
stationary
and
tighten
mounting
bolt
.
Tightening
Torques
I
CAUTION-
"
Pulley
to
vibration
damper
..
.
.
.
....
22
Nm
(17
ft-Ib)
lf
the
camshaftsare
not
properly
timed,
the
1
pis-
tons
can
contact
thevalves
.
"
Vibration
damper
tocrankshaft
M16
stretch
bolt
(always
replace)
.
330
Nm
(244
ft-Ib)
CAMSHAFT
TIMINGCHAINS,
6-CYLINDER
20
.
Installation
of
remaining
parts
is
reverse
of
removal
.
When
installing
thermostat,
make
sure
arrow
or
vent
hole
faces
up
.
Refill
cooling
system
as
described
in
170
Radiator
and
Cooling
System
.
Tighteníng
Torques
"
Coolant
drain
plug
to
cylinder
block
.
..
.
.
.
...
.
..
.....
25
Nm
(18
ft-Ib)
"
Radiator
cooling
fan
to
coolant
pump
.
..
.
...
...
..
.....
40
Nm
(30
ft-Ib)
"
Radiator
drain
screw
to
radiator
....
2
.5
Nm
(22
in-lb)
Camshaft
timing
chainremovalon
6-cylinder
engines
re-
quires
that
you
Rmove
the
engine
oil
pan
by
raising
the
en-
gine
and/or
lowering
the
front
suspension
crossmember
.
Special
BMW
service
tools
are
needed
for
timing
chain
re-
moval
and
installation
procedures
.
The
special
tools
assure
proper
timing
of
the
valvetrain
.
Precise
marks
to
setthe
timing
on
the
camshafts
arenot
provided
for
reassembly
.
Read
the
procedures
through
before
beginning
thejob
.
Camshaft
timing
chains,
removing
(6-cylinder
engines)
1
.
Disconnect
negative
(-)
cable
from
battery
.
CA
UTION-
Disconnecting
the
battery
may
erase
fault
codes)
stored
in
control
module
memory
.
Check
for
fault
codes
using
special
BMW
diagnostic
equipment
.
2
.
Drain
engine
coolant
.
Drain
engine
block
by
removing
block
drain
.
Remove
radiator
cooling
fan
shroud
and
cooling
fan
.
See170
Radiator
and
Cooling
System
.
.
WARNING
-
Allow
the
engine
to
cool
before
openingor
draining
the
system
.
CAUTION-
Radiator
fan
has
left
hand
threads
.
NOTE-
The
block
drain
plug
is
located
on
the
exhaust
side
of
the
engine,
below
cylinder
no
.
4
.
3
.
Drain
engine
oíl
andremove
oil
pan
.
See
119
Lubrica-
tion
System
.
4
.
Remove
alternator
cooling
duct
.
5
.
Remove
two
large
coolant
hoses
from
thermostat
housing
.
Remove
engine
lifting
bracket
and
thermostat
housing
from
front
of
cylinder
head
.
6
.
Loosen
bolts
for
coolant
pump
pulley
.
Then
remove
drive
belts
for
alternator
andA/C
compressor
.
See
020
Maintenance
Program
.
Remove
coolant
pump
pulley
.
Fig
.
16
.
NOTE-
OnM50
engines
with
a
two-roller
drive
belt
tensioner,
remove
the
upper
rollerto
access
thetensioner
mount-
ing
bolts
.
NOTE-
Make
note
of
the
arrangement
of
the
rubber
insulators
when
removing
the
cylinder
head
cover
mounting
bolts
.
CAMSHAFT
TIMING
CHAIN
117-
7
Fig
.
16
.
Drive
belt
tensioner
mounting
bolts
(arrows)
.
B11055
7
.
Remove
drive
belt
tensioner
from
front
of
engine
.
See
Fig
.
17
.
1992-1995
M50
engine
speed
sensor
on
timing
cover
(ar-
row)
.
10
.
Unclip
andremove
baffle
cover
from
above
intake
cam-
shaft
.
See
Fig
.
18
.
11
.
On
1992
engines
:
Remove
upper
timing
chain
cover
from
front
of
cylinder
head
.
See
Fig
.
19
.
8
.
Remove
engine
speed
sensor
from
lower
timing
chain
12
.
Loosen
spark
plugs
.
See
120
Ignition
System
.
cover,
if
applicable
.
See
Fig
.
17
.
13
.
Set
engine
to
approximate
TDC
by
rotating
in
normal
9
.
Remove
cylinder
head
cover
.
See
113
Cylinder
Head
operating
direction
until
camshaft
lobes
at
cylinder
no
.
Removal
and
Installatíon
.
1
are
facing
each
other
.
See
Fig
.
20
.
14
.
Set
engine
to
TDC
by
aligning
"0/T'
mark
(0°TDC)on
front
vibration
damper
with
cast
bosson
lower
timing
chain
cover
.
See
Fig
.
21
.
15
.
Remove
vibration
damper
mounting
bolts
and
remove
vibration
damper
and
pulley
.
See
Fig
.
22
.
CAMSHAFT
TIMING
CHAINS,
6-CYLINDER