
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
.
44
.
Secondary
chain
sprockets
and
chain
being
installed
.
Attachsprockets
with
arrows
pointing
upand
elongated
holes
cen-
tered
.
CYLINDER
HEAD
REMOVAL
AND
INSTALLATION
113-17
Spring
17
plate
0012543
Fig
.
45
.
VANOS
spring
plate
and
thrust
washerson
later
engines
.
14
.
Insta¡¡
BMW
special
tool
no
.
11
3
390
into
primary
tim-
ing
chain
tensioner
sleeve
.
Thread
tool
in
finger
tight
until
siack
is
removed
from
chain
.
NOTE-
BMW
special
tool
no
.
11
3
390
is
a
dummy
primary
chain
tensioner
and
simulatesthe
function
of
the
ten-
sioner
.
15
.
Insta¡¡
VANOS
unit
as
described
in
117
Camshaft
Tim-
ing
Chain
.
CAUTION-
Special
ínstallation
instructions
apply
when
mounting
the
VANOS
unit
to
the
cylinder
head
.
Be
sure
to
follow
the
procedurefound
in
117
Cam-
shaft
Timing
Chain
.
16
.
Slowlyuniock
and
release
secondary
chain
tensioner
.
17
.
Preloadprimary
chain
by
tightening
BMW
special
tool
no
.
11
3390
(dummy
chain
tensioner)
to
1.3
Nm
(11
in-
lb)
.
Then
tighten
exhaust
secondary
camshaft
sprocket
mounting
bolts
in
two
stages
.
Tightening
Torque
"
Secondary
timing
chain
sprocket
to
exhaust
camshaft
(Torx
bolts)
Stage
1
.
.............
..
..
.
...
5
Nm
(44
in-lb)
Stage
2
..............
..
..
.
,
.
..
22
Nm
(17
ft-1b)
18
.
Remove
flywheel
locking
tool
from
transmission
bell-
housing
.
Remove
camshaft
locking
tool
from
rear
of
cylinder
head
.
19
.
Turn
engine
over
by
hand
at
least
two
fui¡
crankshaft
ro-
tations
.
Reinstall
camshaft
locking
tool
and
flywheel
locking
toolto
make
sure
al¡
adjustments
are
still
cor-
rect
.
lf
settings
are
correct,
remove
locking
tools
.
20
.
Remove
BMW
special
tool
11
3390
(dummy
chain
ten-
sioner)
from
side
of
cylinder
head
.
CAUTION-
Mountintake
camshaft
sprocket
so
thatcollar
side
21
.
Insta¡¡
primary
chain
tensioner
so
that
cutout
in
tension-
of
the
sprocket
faces
camshaft
.
er
piston
engages
chain
rail
.
See
Fig
.
46
.
Using'new
seals,
install
and
tighten
access
plugs
in
VANOS
con
13
.
Install
and
tighten
exhaust
camshaft
sprocket
mounting
trol
unit
.
boits
finger
tight
only
.
Tighten
intake
camshaft
sprocket
mounting
nuts
to
specified
torque
.
Tightening
Torques
"
Access
plugs
Tightening
Torque
to
VANOS
control
unit
.
..
.
.
........
50
Nm
(37
ft-Ib)
"
Intake
camshaft
sprocket
"
Primary
camshaft
timing
chain
tensioner
mounting
nuts
(M6)
..............
10
Nm
(89
in-lb)
to
tensioner
sleeve
..
...
.
.
........
50
Nm
(37
ft-Ib)
CYLINDER
HEAD,
6-CYLINDER

116-
6
CYLINDER
HEAD
AND
VALVETRAIN
9
.
Camshaft
installation
is
reverse
of
removal,noting
the
following
:
"
Prior
to
installation,
check
al¡
components
for
wear
as
described
below
under
Cylinder
Head
and
Val-
vetrain
Reconditioning
.
"
Crankshaft
must
be
at
least
45°
away
from
MC
before
installing
camshafts
to
cylinder
head
.
"
Lubricate
camshafts
prior
to
installation
.
"
Insta¡¡
camshafts
into
cylinder
head
with
lobes
for
cyl-
inder
no
.
1
pointing
up
and
towards
each
other
.
See
Fig
.
8
.
"
After
installing
camshaft(s),
observe
specified
waiting
time
for
hydraulic
cam
followers
to
fully
compress
be-
fore
bringing
crankshaft
back
to
TDC
.
Fig
.
8
.
Camshaft
correctly
positioned
for
reassembly
so
thatcylinder
no
.
1
lobes
(arrows)
face
each
other
.
Tightening
Torques
"
Camshaft
bearing
caps
to
cylinder
head
(M7)
.
..
...
..
.
....
15
Nm
(11
ft-Ib)
"
Cylinder
head
cover
to
cylinder
head
(M6)
..
.
..........
10
Nm
(89
in-lb)
"
Primary
timing
chaintensioner
to
cylinder
head-see
117
Camshaft
Timing
Chain
"
Spark
plugs
(M12)
.............
.
.
23
Nm
(17
ft-Ib)
"
Timing
chain
sprocket
to
camshaft
flange
(M6)-see
117
Camshaft
Timing
Chain
CYLINDER
HEAD,
DISASSEMBLYAND
ASSEMBLY
Valves,
removing
and
installing
1
.
Remove
cylinder
head
as
described
in
113
Cylinder
HeadRemoval
and
Installation
.
Remove
exhaust
manifold(s)
.
2
.
Remove
camshafts
using
special
tools
as
descríbed
earlier
.
3
.
On
M42
and
al¡
6-cylinder
engines
:
Remove
camshaft
carriers
by
pulling
them
straight
up
off
mounting
studs
.
CAUTION-
"
Do
not
let
the
hydraulic
cam
followers
fa¡¡
out
as
the
camshaft
carrier
is
removed
.
Special
suction
cupsare
available
from
BMW
to
hold
the
hydrau-
lic
cam
followers
in
place
during
carrier
removal
.
Camshaft
installation
waiting
times
"
at
or
above
68°F
(20
0
C)
....
..
.
..
......
10
minutes
"
50-68°F
(10-20°C)
...
.
..
....
.
..
......
30
minutes
"
32-50°F
(0-10°C)
....
.
..
....
.
..
......
75
minutes
4
.
On
M44
engines
:
Remove
all
hydraulic
valve
adjusters
.
See
Hydraulicvalve
adjusters,
checking
and
re-
"
Reinstall
timing
chainsprockets
and
tensioner
as
spe-
placing
(M44
engine),
later
in
this
section
.
cifically
described
in
117
Camshaft
Timing
Chain
.
"
Waít
at
least
10
minutes
before
cranking
engine
over
CAUTION-
withstarter
motor
for
the
first
time
.
Hydraulic
valve
adjusters
should
be
stored
in
an
upright
position
.
lf
necessary,
use
amagnetic
tool
to
aid
in
removal
of
the
adjusters
.
"
Hydraulic
cam
followers
shouldbe
stored
in
an
upright
position
.
5
.
Remove
valves
using
a
valve
spring
compressor
.
NOTE-
"
The
M44
cylinder
head
has
recessed
valve
stems
.
This
requires
the
use
of
a
special
valve
spring
com-
pressor
tool
.
"
Label
each
valve
assembly
as
it
is
removed
so
it
can
be
installed
in
its
original
position
.
6
.
Remove
and
discard
valve
stem
oil
seals
from
valve
guides
.
See
Valve
stem
oil
seals
later
in
this
section
.
7
.
Valve
installation
is
reverse
of
removal
.
"
Reinstall
exhaust
manifold(s)
with
new
gaskets
.
Use
Molycote
HSC'
5
or
equivalent
anti-seize
thread
com-
pound
on
fasteners
.
Tightening
Torque
"
Exhaust
manifold
to
cylinder
head
M7
............
..
...
....
.
...
..
20
Nm
(15
ft-Ib)

NOTE-
The
vibration
damper
center
bolt
is
very
tight
.
A
heavy
duty
holding
device,
such
as
BMW
special
tool
no
.
112
150,
should
be
used
to
hold
the
vibration
damper
hub
V
stationary
while
the
bolt
is
loosened
.
v
11
.
Usingloosened
bolt
at
vibration
damper,
turn
crank-
shaft
to
TDC
and
lock
in
position
by
inserting
BMW
special
tool
no
.
11
2
300
through
transmission
bell-
-
p
housing
.
See
Fig
.
5
.
v
O
NOTE-
I\
0011966a
"
If
necessary,
remove
plugfrom
locating
boye
in
lower
edge
of
bell
housing
.
"
Confirm
that
locatng
tool
has
been
correctlyinstalled
by
trying
to
rotate
the
crankshaft
.
Fig
.
7
.
Lower
timing
chain
cover
mounting
bolts
(arrows)
.
Bolts
A
Fig
.
5
.
BMW
special
tool
no
.
11
2300
installed
through
bellhousing
are
installed
through
hollow
locating
dowels
.
and
finto
flywheel
to
lock
crankshaft
at
TDC
(arrow)
.
CA
UTION-
Thecamshafts
mustbe
locked
in
the
MC
position
using
the
specialservice
tool
before
removing
the
timing
chain
.
The
tool
holds
the
camshafts
parallel
to
each
other
and
perpendicular
to
the
valve
cover
gasket
surface
.
12
.
Lockcamshafts
at
TDC
bymounting
BMW
special
tool
no
.
113
240
over
square
ends
of
camshafts
.
See
Fig
.
6
.
"
Check
that
tool
is
squarely
seated
on
cylinder
head
gasket
surface
.
If
necessary,
rotate
camshafts
slightly
using
an
open-end
wrench
at
hexon
camshafts
.
13
.
Remove
lower
timing
chaincover
mounting
bolts
and
carefully
lift
cover
off
.
Clean
sealing
surfaces
and
gas-
ket
grooves
.
See
Fig
.
7
.
14
.
Remove
hydraulic
chaintensioner
from
right
side
of
cyl-
inder
head
.
See
Fig
.
8
.
CAMSHAFT
TIMING
CHAIN
117-
3
Fig
.
6
.
BMW
special
tool
no
.
11
3240
installed
on
rearof
camshafts
to
position
camshafts
at
TDC
.
(M44
camshafts
shown
.
Other
engines
are
similar
.
Fig
.
8
.
Hydraulic
chain
tensionerplug
(arrow)
.
CAMSHAFT
TIMING
CHAIN,
4-CYLINDER

M42
Engine
CL
(EM
Fig
.
11
.
Two
versionsof
hydraulic
chaintensioners
.
Original
chain
ten-
sioner
on
M42
engine
(top)
canbe
disassembled
.
Chain
ten-
sioner
on
M44
engine
(bottom)
cannot
be
disassembled
.
Note
differences
in
outer
sleeve
.
Also,
the
M42
tensioner
de-
tent
ring
groove
is
visible
when
tensioner
is
extended
(arrow)
.
Outer
sleeve
Spring
0013024a
Detent
ring
9
.
On
M44
engines
:
Clamp
tensioner
piston
in
vice
(soft
jaws)
and
squeeze
oil
from
it
.
Slowly
compress
piston
only
up
to
end
círclip
.
Repeat
procedure
twice
to
ensure
al¡oil
is
expelled
.
See
Fig
.
13
.
10
.
Insta¡¡
hydraulic
chain
tensioner
lo
cylinder
head
.
Usea
new
sealing
washer
on
tensionerplug
when
installing
.
Tightening
Torque
"
Chain
tensioner
to
cylinder
head
....
40
Nm
(30
ft-Ib)
11
.
On
M42
engines
:
Release
early-style
chain
tensioner
by
pressing
chain
guide
against
tensioner
until
it
un-
locks
and
expands
out
.
CAMSHAFT
TIMING
CHAIN
117-
5
0012507
Fig
.
13
.
When
reinstalling
chain
tensiones,
oil
in
tensioner
piston
must
first
be
expelled
by
compressing
piston
in
vise
.
When
com-
pressing
piston,
only
compress
up
to
and
circlip
(arrow)
.
Tightening
Torque
"
Chain
sprocket
lo
camshaft
flange
(M6)
..
.
..
.............
.
..
10
Nm
(89
in-lb)
13
.
Remove
crankshaft
locking
tool
from
bellhousing
and
camshaft
locking
tool
from
rear
of
cylinder
head
.
14
.
Install
lower
timingchain
cover
:
"
Insta¡¡
new
crankshaft
oil
seal
in
cover
.
"
Use
new
gaskets
when
installing
cover
.
"
Thoroughly
clean
profile
gasketgroove
and
all
gasket
sealing
surfaces
on
lowerchaincover
.
"
Apply
a
small
bead
of
silicon
sealer
(3-Bond
1209
or
Snap
equivalent)
lo
joint
corners
where
chaincover
meets
ring
0013024
head
and
block
.
See
Fig
.
14
.
"
Tap
cover
into
position
to
engage
locating
dowels
.
Fig
.
12
.
Disassembled
early-style
chain
tensioner
usadon
M42
en-
"
Tighten
cover
mounting
bolts
alternately
and
in
stages
.
gine
.
12
.
Check
that
chain
is
now
free
of
siack
.
Tighten
down
sprocket
mounting
bolts
.
where
chain
cover
meets
head
and
block
(arrows)
.
Fig
.
14
.
Apply
sealer
(3-Bond
1209
0
or
equivalent)
to
joint
corners
CAMSHAFT
TIMING
CHAIN,
4-CYLINDER

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
.

9)
B11126
Fig
.
29
.
Lower
timing
chain
cover
mounting
bolts
(arrows)
anddowel
locations
(A)
.
Coolant
hose
fitting
B
is
replaced
by
coolant
pipe
pressure
fitting
in
later
models
.
28
.
Remove
remaining
Torx
bolt
from
timing
chain
guide
.
See
Fig
.
30
.
Fig
.
30
.
Timing
chainguide
mounting
bolt(A)
.
CAMSHAFT
TIMING
CHAIN
117-
11
29
.
Lift
primary
chain
sprocket
off
exhaust
camshaft
and
remove
chain
.
NOTE-
"
If
any
of
the
sprockets
are
being
replaced
due
to
wear,
the
chain
should
also
be
replaced
.
"
If
the
crankshaft
sprocket
requires
replacement,
the
oil
pump
drive
sprocket
and
chain
must
be
removed
as
described
under
119
Lubrication
System
.
Camshaft
timing
chains,
installing
(6-cylinder
engines)
Inspecttiming
chainsprockets
.
Sprockets
that
haveworn
or
missing
teeth
should
be
replaced
.
Inspect
guide
rail
and
ten-
sioner
rail
for
deep
grooves
caused
by
chain
contact
.
Replace
any
parí
that
is
worn
.
The
procedure
outlined
below
assumes
that
the
camshafts
and
the
crankshaft
are
locked
in
the
TDC
installation
position
with
special
tools
(shown
earlier
in
Fig
.
23
and
Fig
.
24)
.
NOTE-
NOTE-
On
pre-VANOS
engines
(engines
built
up
to
8-92),
the
"
The
timing
chain
cover
can
be
removed
with
the
cool-
camshaft
locking
tool
(Fig
.
24)should
be
raised
upon
ant
pump
installed
.
eitherside
by
3mm
(use
feeler
gauge
or
dril¡
bits)
.
Be
sure
the
clamping
bolts
on
tool
are
loose
and
thecenter
"
Use
care
when
removing
the
chain
cover
from
the
of
the
tool
is
contacting
the
cylinder
head
surface
.
This
coolant
pipe
or
hose
at
the
rearof
the
cover
.
service
campaign
helps
improve
idle
characteristics
by
reducing
valve
overlap
.
1
.
Install
primary
timing
chain
to
crankshaft
sprocket
and
tie
it
up
through
cylinder
head
opening
.
2
.
Using
new
gaskets
and
coolant
pipe
O-ring
;
insta¡¡
low-
ertiming
chain
cover
:
"
Drive
timing
cover
doweis
inuntil
they
just
protrude
slightly
from
sealing
surface
.
"
Apply
a
small
bead
of
silicon
sealer
(3-Bond
1209
©
or
equivalent)
to
corners
of
cylinder
head
where
timing
cover
meets
cylinder
head
and
engine
block
.
"
Tap
cover
into
position
to
engage
doweis
.
"
Install
mounting
bolts
hand
tight,
including
two
outer
Torx
bolts
from
above
.
"
Drive
doweis
in
flush
to
front
of
cover
.
"
Tighten
cover
mounting
bolts
alternately
and
in
stages
.
Tightening
Torque
"
Lower
timing
cover
to
cylinder
block
M7
................
...
..
.
.....
15
Nm
(11
ft-Ib)
M8
.............
.
.
...
.........
20
Nm
(15
ft-Ib)
3
.
Insta¡¡
oil
pan
using
a
new
gasket
.
See
119
Lubrication
Systern
.
CAMSHAFT
TIMINGCHAINS,
6-CYLINDER