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
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
.
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
.
113-
1
8
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
CYLINDER
HEAD,
6-CYLINDER
Fig
.
46
.
Primary
chaintensioner
being
installed
.
Piston
cutout
must
engage
chain
rail
.
22
.
Install
intake
cam
cover
and
then
install
cylinder
head
cover
.
Check
for
correct
seating
of
half-moons
in
back
of
cylinder
head
cover
.
Use
a
small
amount
of
3-Bond
O
1209
orequivalent
seaiant
at
corners
of
half-moon
cut-
outs
.
23
.
Install
front
exhaust
pipes
to
manifolds
using
new
gas-
kets
and
nuts
.
Coat
manifold
studs
with
copper
paste
prior
to
installing
nuts
.
24
.
Installationof
remaining
parts
is
reverse
of
removal
.
Refill
cooling
system
as
described
in
170
Radiator
and
Cooling
System
.
Change
engine
oil
and
filter
as
de
scribed
in
020
Maintenance
Program
.
Check
adjust-
ment
of
accelerator
cable
.
Additional
tightening
torques
are
given
below
.
Reconnect
battery
last
.
25
.
Installationof
remaining
parts
is
reverse
of
removal,
noting
the
following
:
"
Make
sure
all
sealing
surfaces
are
clean
and
free
of
old
gasket
material
.
Insta¡¡
new
intake
manifold
gasket
.
"
Reinstall
harness
connectors
for
oil
pressure
switch
and
coolant
temperature
sensor
before
installing
in-
take
manifold
.
"
Refill
cooling
systemas
described
in
170
Radiator
and
Cooling
System
.
"
Change
engine
oil
and
filter
as
described
in
020
Main-
tenance
Program
.
"
If
necessary,
adjust
accelerator
cable
.
"
Reconnect
battery
last
.
CAUTION-
To
prevent
damaging
engine
electronic
systems,
be
sure
to
install
all
ground
wirespreviously
re-
moved,
including
the
ground
wires
at
the
cylinder
head
for
the
ignition
coils
.
Tightening
Torque
Tightening
Torques
"
Cylinder
head
cover
"
Coglant
drain
plug
to
cylinder
block
.
.
25
Nm
(18
ft-Ib)
to
cylinder
head(M6
screws)
.
.
.....
10
Nm
(89
in-lb)
"
Intake
manifold
to
cylinder
head
.
...
.
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)
117-
1
4
CAMSHAFT
TIMING
CHAIN
22
.
Installation
of
remaining
parts
is
reverse
of
removal,
When
theengine
is
running,
the
piston
housing
is
supplied
noting
the
following
:
with
pressurized
engine
oil
.
At
idie,
the
solenoid
isin
the
off
"
When
installing
thermostat,
make
sure
arrow
or
vent
position
(de-energized)
and
valve
timing
is
maintained
in
the
hole
faces
up,
if
applicable
.
normal
position
:
When
the
solenoid
is
energized,
the
gear
cup
"
Refill
cooling
systemas
described
in
170
Radiator
piston
moves
forward
to
advance
the
camshaftby
a
maximum
and
Coming
System
.
of
12
.5
.
"
Install
oil
pan
as
described
in
119
Lubrication
Sys-
tem
.
"
Fill
engine
with
oil
and
install
a
new
oil
filter
as
de-
scribed
in
020
Maintenance
Program
.
"
Insta¡¡
ground
wires
at
cylinder
head
cover
mounting
studs
and
at
front
of
cylinder
head
and
thermostat
housing,
where
applicable
.
VANOS
system
operation,
testing
Tightening
Torques
There
are3
special
tools
required
to
check
VANOS
opera-
"
Coolant
drain
plugto
cylinder
block
.
.
25
Nm
(18
ft-Ib)
tion
;
an
electricaltest
lead
(BMW
special
tool
no
.
12
6
410),
an
"
Radiator
cooling
fan
to
coolant
pump
.
40
Nm
(30
ft-Ib)
air
line
fitting
(BMW
special
tool
no
.
11
3
450),
and
a
crank-
"
Radiator
drain
screw
to
radiator
...
.
2
.5
Nm
(22
in-Ib)
shaft
TDC
locking
tool
(BMW
special
tool
no
.
112
300)
.
"
Upper
timing
chaincover
to
cylinder
head
The
test
leal
is
used
to
power
the
solenoid,
simulating
the
M6
nut
...
.....
.............
..
.
10
Nm
(89
in-lb)
ground
signal
from
the
DME
control
unit
.
The
air
line
fitting
M8
bolt
.....
....
.
.
.............
22
Nm
(17
ft-Ib)
takes
the
place
of
the
oil
supply
line
fitting
to
simulate
oil
Ares-
"
VANOS
control
unit
to
cylinder
head
sure
.
The
locking
tool
positions
and
locks
the
crankshaft
at
M6
nut
.........
..
..
.
..........
10
Nm
(89
in-lb)
TDC,
cylinder
no
.
l.
M8
bolt
........
...
.............
22
Nm
(17
ft-Ib)
"
VANOS
oil
supply
pipe
to
VANOS
control
unit
1
.
Remove
alternator
cooling
air
duct
.
banjo
bolt
.......
..
..
.
..........
32
Nm
(24
ft-Ib)
VANOS
(VARIABLE
VALVE
TIMING)
3
.
Remove
top
plastic
enginecovers
.
Disconnect
ignition
coil
harness
connectors
fromcofs
.
Remove
ignition
1993
and
later
6-cylinder
engines
are
equipped
with
a
vari-
coils
.
able
valve
timing
system
called
VANOS
.
This
system
is
con-
trolled
by
the
engine
management
system
and
dynamically
4
.
Remove
cylinder
head
cover
mounting
bolts
and
re-
adjusts
intake
camshaft
timing
based
on
engine
load,
engine
move
cylinder
head
cover
.
Unclip
andremove
oil
baffle
speed
and
engine
temperature
.
cover
from
above
intake
camshaft
.
See
113
Cylinder
Head
Removal
and
installation
.
The
main
components
of
the
VANOS
system
are
the
control
unit
with
piston
housing
and
integral
spool
valve,
and
the
mod-
ified
intake
camshaft
.
See
Fig
.
35
.
VANOS
(VARIABLE
VA
LVE
TIMING)
Fig
.
35
.
VANOS
control
unit
with
modified
intake
camshaft
.
B11001
WARNING
-
Special
BMW
service
tools
are
required
to
check
and
repair
the
VANOS
System
.
Read
theproce-
dures
through
before
beginning
the
job
.
2
.
Disconnect
crankcase
ventilation
hose
fitting
from
cyl-
inder
head
cover
.
NOTE-
Note
the
arrangement
of
the
cylinder
head
cover
bolt
insulators
and
gaskets
during
removal
.
5
.
Set
engine
to
approximate
TDC
by
rotating
in
normal
operating
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
.
See
Fig
.
20
.
6
.
Set
engine
to
TDC
by
aligning
"0/T"
mark
(0°TDC)on
front
vibration
damper
withcast
boss
on
lower
timing
chain
cover
.
See
Fig
.
21
.
7
.
Lock
crankshaft
in
position
by
inserting
BMW
special
tool
no
.
11
2
300
through
transmission
bellhousing
and
into
hole
in
flywheelor
driveplate
.
See
Fig
.
36
.
NOTE-
Confirm
that
the
locking
tool
has
been
correctly
in-
stalled
by
trying
to
rotatethe
crankshaft
.
117-
1
6
CAMSHAFT
TIMING
CHAIN
15
.
Remove
crankshaft
locking
tool
.
Remove
special
test
equipment
.
Insta¡¡
oil
supply
line
using
new
seals
and
reconnect
solenoid
connector
.
Remainder
of
installa-
tion
is
reverse
of
removal
.
Tightening
Torque
"
Cylinder
head
cover
to
cylinder
head
.
10
Nm
(89
in-lb)
"
VANOS
oil
supply
line
to
VANOS
control
unit
(banjo
bolt)
..
.........
32
Nm
(24
ft-Ib)
"
VANOS
solenoidlo
VANOS
control
unit
........
.
.
.
..
........
30
Nm
(22
ft-Ib)
VANOS
control
unit,
removing
Special
BMW
service
tools
are
required
lo
remove
and
in-
stall
the
VANOS
control
unit
.
Read
the
procedure
through
be-
forestarting
the
job
.
1
.
Remove
radiator
cooling
fan
shroud
and
cooling
fan
.
See
170
Radiator
and
Cooling
System
.
CAUTION-
Radiator
fan
has
left
hand
threads
.
2
.
Remove
top
plastic
engine
covers
.
Disconnect
ignition
coil
harness
connectors
from
coils
.
Remove
ignition
coils
.
Remove
cylinder
head
cover
.
Unclip
andremove
oil
baffle
cover
from
above
intake
camshaft
.See
113
Cylinder
Head
Removal
and
Installation
.
NOTE-
Make
note
of
the
mounting
bolt
insulator
arrangement
during
removal
of
the
cylinder
head
cover
.
3
.
Set
engine
lo
TDC
by
rotating
engine
in
normal
operat-
ing
direction
until
camshaft
lobes
at
cylinder
no
.
1
are
facing
each
other
and
"0/T"
mark
(0°TDC)
on
vibration
damper
lines
up
with
cast
boss
on
lower
timing
chain
cover
.
See
Fig
.
38
.
4
.
Lock
crankshaft
at
TDC
by
inserting
BMW
special
tool
no
.
11
2
300
through
transmission
bellhousing
and
finto
flywheel
or
drive
plate
.
Refer
to
Fig
.
36
given
earlier
.
NOTE-
Confirm
that
the
locking
tool
has
been
correctly
in-
stalled
by
trying
to
rotatethe
crankshaft
.
5
.
Remove
three
cylinder
head
cover
mounting
studs
from
rear
of
head
.
Lockcamshafts
at
TDC
bymounting
BMW
special
tool
no
.
11
3
240
at
ends
of
camshafts
.
Check
that
tool
is
squarely
seated
on
cylinder
head
gasket
surface
.
If
necessary,
rotate
camshafts
slightly
using
a24
mm
wrench
.
Refer
to
Fig
.
24
given
earlier
.
VANOS
(VARIABLE
VALVE
TIMING)
Fig
.
38
.
Camshafts
positioned
at
TDC-Cyl
.
No
.
1
cam
lobes
face
in
Note
0/T
mark
(0°TDC)
on
vibration
damper
alígned
with
boss
on
front
cover
.
CA
UTION-
Thecamshafts
mustbe
locked
in
the
TDC
position
using
the
specialservice
tool
or
an
equivalent
be-
fore
removing
the
timing
chain
.
Thearrows
on
the
sprockets
should
not
be
used
to
accurately
set
the
engine
to
TDC
The
special
tool
holds
the
cam-
shafts
parallel
to
each
other
and
perpendicular
to
the
valve
cover
gasket
surface
.
6
.
Disconnect
harness
connector
and
oil
line
fitting
from
bottom
of
VANOS
control
unit
.
NOTE-
Wrap
the
VANOS
oilfine
fitting
with
a
shop
rag
to
ab-
sorb
leaking
oil
.
7
.
Remove
two
access
plugs
from
VANOS
control
unit
in
frontof
exhaustcamshaft
sprocket
.
Loosen
4exhaustcamshaft
sprocket
mounting
bolts
but
do
not
remove
(Torx
El
0
socket)
.
NOTE-
Removal
of
the
access
plugs
allows
the
lower
exhaust
camshaft
sprocket
mounting
bolts
to
be
accessed
.
8
.
Depress
secondary
timing
chain
tensioner
and
lock
it
in
down
position
by
inserting
a
stiff
wire
into
rear
of
ten-
sioner
.
See
Fig
.
27
.
9
.
Remove
VANOS
control
unít
mounting
nuts
and
boltat
front
of
cylinder
head
.
117-
1
8
CAMSHAFT
TIMING
CHAIN
CAUTION-
It
is
crítical
that
the
exhaustcamshaft
sprocket
be
turned
only
the
mínimum
amount
necessary
to
engage
the
gear
cup
.
If
this
procedure
is
done
ín-
correctly,
the
VANOS
system
may
not
function
throughout
íts
full
range
.
NOTE-
As
the
control
unit
isinstalled,
the
secondary
sprockets
will
rotate
in
the
counterclockwise
direction
.
It
may
be
necessary
to
guide
sprockets
counterclockwise
as
the
control
unit
is
installed
.
8
.
On
cars
built
from3/95
:
Use
a
spanner
tool
(See
Fig
.
39
.),
turn
exhaust
sprocket
counterclockwise
(as
víewed
from
front
of
engine)
only
enough
to
mesh
gear
cup
splines
with
camshaftgear
.
Slowly
push
VANOS
control
unit
towards
camshaft
until
it
is
fully
seated,guiding
chains
in
counterclockwise
direction
.
CA
UTION-
Ensure
that
the
first
available
tooth
engages
.
9
.
Install
and
tightencontrol
unit
nuts
and
bolt
.
10
.
Connect
harness
connector
to
VANOS
solenoid
.
Using
new
seals,
insta¡¡
oil
line
fitting
.
Tightening
Torques
"
VANOS
control
unitto
cylinder
head
M6
nut
.....
..
..
.
.
.............
10
Nm
(89
in-lb)
M8
bolt
.....
.
.
.
.
..
.............
22
Nm
(17
ft-Ib)
"
VANOS
oil
supply
line
to
control
unit
.
32
Nm
(24
ft-Ib)
11
.
Slowlyunlock
and
release
secondary
chain
tensioner
.
12
.
Preloadprimary
chain
by
tightening
BMW
special
tool
no
.
112
240
(dummy
chain
tensioner)
to
1
.3
Nm
(11
in-
lb)
.
Then
tighten
exhaust
camshaft
sprocket
mounting
bolts
alternately
in
two
stages
.
Tightening
Torque
"
Secondarytiming
chain
sprockets
to
camshafts
(Tora
boits)
Stage
1
..
...............
...
.
.
...
5
Nm
(44
in-lb)
Stage
2
..
...............
...
.
.
..
22
Nm
(17
ft-Ib)
VANOS
(VARIABLE
VALVE
TIMING)
13
.
Remove
flywheel
locking
tool
from
transmission
bell-
housing
.
Remove
camshaft
locking
tool
from
rear
of
cylinder
head
.
14
.
Turn
engine
over
by
hand
at
least
two
fui¡
crankshaft
ro-
tations
.
Reinstall
camshaft
locking
tool
and
flywheel
locking
toolto
make
sure
all
adjustments
are
correct
.
If
settings
are
correct,
remove
locking
tools
.
15
.
Remove
BMW
special
tool
112
420
(dummy
chain
ten-
sioner)
from
side
of
cylinder
head
.
Install
primary
chain
tensioner
so
that
cutout
in
tensioner
piston
engages
chain
rail
.
See
Fig
.
34
.
Using
new
seals,
install
and
tighten
access
plugs
in
VANOS
control
unit
.
Tightening
Torque
"
Access
plugs
to
VANOS
control
unit
.
..
.
.....
.
..
...
50
Nm
(37
ft-lb)
"
Primary
timing
chain
tensioner
plug
to
tensioner
sleeve
M50/S50USengine
.
.
..
.
.
...
.
...
..
50
Nm
(37
ft-Ib)
M52/S52US
engine
...
..
...
...
...
40
Nm
(30
ft-Ib)
16
.
Install
oil
baffle
cover
above
intake
camshaft
.
Install
three
cylinder
head
covermounting
studs
to
rear
of
head
.
Instali
cylinder
head
cover
.
Tightening
Torque
"
Cylinder
head
cover
to
cylinder
head
(M6
screws)
......
10
Nm
(89
in-Ib)
17
.
Installationof
remaining
parts
is
reverse
of
removal
.
NOTE-
Be
sure
to
install
the
ground
wíres
at
the
cylinder
head
cover
mounting
studs
and
at
the
front
of
the
cylinder
head,
if
applicable
.