020-
1
0
MAINTENANCE
PROGRAM
1.
Run
engine
for
afewminutes
to
warm
engine
oil
.
Shut
5
.
When
oil
flow
has
diminished
to
an
occasional
drip,
re-
engine
off
.
install
drain
plugwith
a
new
metal
sealing
washerand
torque
plug
.
2
.
With
car
on
level
ground,
place
drain
pan
under
oil
drain
plug
.
See
Fig
.
5
.
Tightening
Torques
"
Engine
oil
drain
plug
M12
bolt
(17mm
wrench)
.
...
.
..
.
25
Nm
(18
ft-Ib)
-
M22
bolt
(19mm
.
wrench)
...
.
...
.
60
Nm
(44
ft-Ib)
Fig
.
5
.
Engine
oil
drain
plug(arrow)
in
oil
pan
.
3
.
Remove
filter
housingcover
.
Remove
filter
cartridge
and
discard
any
O-rings
.
See
Fig
.
6
.
CAUTION-
Pulí
the
loose
plug
away
from
the
hole
quickly
to
avoidbeing
bumed
by
hot
oil
.
It
wíll
runout
quickly
when
the
plug
ís
removed
.
If
possible,
use
gloves
to
protect
your
hands
.
ENGINE
COMPARTMENT
MAINTENANCE
0012460
Fig
.
6
.
Engine
oil
filter
cartridge
.
Note
O-ring
locations
when
removing
cover
and
filter
.
4
.
Using
a
socket
or
box
wrench,
loosen
drain
plug
at
oil
drain
pan
.
By
hand,
remove
plug
and
letoil
drain
into
pan
.
6
.
Lubricate
and
install
new
O-rings
.
Install
a
new
filter
cartridge
and
housingcover
.
Tighten
cover
.
See
Fig
.
7
.
7
«
a~
.~~
fT~
iII~IIIi~
.
Fig
.
7
.
Oil
flter
housing
on
6-cylínder
engine
.
4-cylinder
engine
is
similar
.
Tightening
Torque
"
Engine
oil
filter
cover
to
oil
filter
housing
...................
25
Nm
(18
ft-Ib)
7
.
Refill
crankcase
with
oil
.'Approximate
oil
capacity
is
list-
ed
in
Tablee
.
Use
dipstick
to
check
correct
oil
level
.
8
.
Start
engine
and
check
that
oil
pressure
warning
light
immediately
goes
out
.
9
.
Allow
engine
to
run
for
a
few
minutes
to
círculate
new
oil,
then
check
for
leaks
at
drain
plug
and
oil
filter
.
Stop
engine
and
reclieck
oil
level
.
ENGINE
COMPAR
ENT
MAINTENANCE
The
information
underthis
heading
describes
routine
mainte-
nance-other
than
oil
change-done
in
the
engine
compart-
ment
.
It
is
not
necessary
for
the
car
to
be
raised
and
supported
off
the
ground
.
Information
on
oil
change
is
given
earlier
under
Engine
Oil
Change
.
020-
1
4
MAINTENANCE
PROGRAM
uu11989
Fig
.
14
.
Engine
drive
belt
tensíoner
being
released
on
late
4-cylinder
engine
.
Pry
off
tensioner
cover
and
then
lever
tensioner
in
clockwise
direction
(as
facing
engine)
and
slip
beltoff
pulleys
.
Fig
.
17
.
Engine
drive
belt
routing
for
late
4-cylinder
engine
with
poly-
ribbed
drivebelts
.
CA
UTION-
Use
only
BMW
approved
phosphate-free
anti-
freeze
when
filling
the
cooling
system
.
Use
of
anti-
B11177
freeze
containing
phosphates
!s
considerad
to
be
Fig
.
15
.
Engine
drive
belt
tensioner
being
released
on
6-cylinder
en-
harmful
to
the
cooling
system
.
gine
.
Pry
off
tensioner
cover
and
then
lever
tensioner
in
clock-
wise
direction
(as
facing
engine)
and
slipbelt
off
pulleys
.
A
translucent
expansion
tank,
or
overflow
resenroir,
providesmonitóring
of
coolant
leve¡
.
Because
the
expansion
tank
is
translucent,
thecoolant
level
can
be
checked
visually
without
opening
the
system
.
Always
check
thecoolant
leve¡
with
theen-gine
cold
.
The
coolant
leve¡
should
be
at
the
maximum
mark
on
O
o
'~
I
the
expansion
tank,
as
shown
in
Fig
.
18
.
OO
Hose
connectionhld
b
tiht
s
soueg
an
ddry
.
Coolánt
seepage
indicates
either
that
the
hose
clamp
is
loose,
that
the
pose
is
ENGINE
COMPARTMENT
MAINTENANCE
0012470
Fig
.
16
.
Engine
drive
belt
routing
for
6-cylinder
engine
.
A/C
compres-
sor
drive
belt
not
shown
.
'92
irá
Alternator
belt
Coolant~
0
pp
o0o
Belt
tensioner
Cooling
System
Service
0013000
Cooling
system
maintenance
consists
of
maíntaining
thecoolant
leve¡,
inspecting
hoses
.
Because
the
coolant's
anti-cor-
rosion
and
anti-freeze
additives
gradually
lose
their
effective-
ness,
replacement
of
thecoolant
every
two
years
up
to
1996
models,
and
every
three
years
from
1996
is
recommended
.
Asa
preventive
measure,
replacement
of
the
cooling
system
hos-
es
every
four
years
is
also
recommended
.
damaged,
or
that
the
connection
is
dirty
or
corroded
.
Dried
cool-
ant
has
a
chalky
appearance
.
Hoses
should
be
firm
and
springy
.
Replace
any
hose
that
is
cracked,
that
has
become
soft
and
limp,
or
has
been
contaminated
by
oil
.
See
Fig
.
19
.
Power
steering
fluid,
checking
leve¡
Check
the
power
steering
fluid
level
in
the
fluid
reservoir
.
Park
thecar
on
leve¡
ground
with
the
engine
off
.
The
level
is
cor-
rect
if
it
is
between
the
MIN
and
MAX
marks
on
the
dipstick
.
See
Fig
.
20
.
If
the
leve¡
is
below
the
MIN
mark,
start
the
engine
andadd
fluid
to
the
reservoir
to
bríng
the
leve¡
up
.
Stop
the
engine
and
recheck
the
leve¡
.
Hand-tighten
the
reservoir
cap
.
ignition
Table
b
.
Engine
Management
Systems
engine
has
high
mileage
.
Engine
1
System
4-cylinder
engines
M42
(1992-1995)
Bosch
DME
Ml
.7
M44
(1996-1998)
Bosch
DME
M5
.2
(OBD
II)
6-cylinder
engines
M50
(1992)
Bosch
DME
M3
.1
M50
VANOS
(1993-1995)
Bosch
DME
M3
.3
.1
M52
(1996-1998)
Siemens
MS41
.1
(OBD
II)
S50US
(1995)
Bosch
DME
M3
.3
.1
S52US
(1996-1998)
Siemens
MS41
.1
(OBD
II)
Both
the
4-cylinder
and
6-cylinder
engines
use
a
distributor-
less
ignition
system
with
individual
ignition
coils
for
each
cylin-
der
.
FuelDelivery
Pressurized
fuel
from
the
in-tank
fuel
pump
is
injected
via
solenoid-type
fuel
injectors
.
The
ECM
controls
the
opening
and
closing
of
the
injectors
by
switchingthe
ground
side
of
each
injector
circuit
.
The
exact
amount
of
fuel
injected
is
de-
termined
by
the
amount
of
timethe
injectors
are
open
.
Cooling
System
Whenever
the
engine
is
running,
acoolant
pump
circulates
coolant
through
the
engine
and,
if
either
heater
control
valves
are
open,
through
the
heater
core
in
the
passenger
compart-
ment
.
The
coolant
absorbs
excess
heat
and
carries
it
to
the
ra-
diator
where
it
is
transferred
into
the
passing
airstream
.
A
thermostat
controls
the
flow
of
coolant
through
the
radiator
based
on
engine
temperature
.
Lubrication
System
The
lubrication
system
is
pressurized
whenever
theengine
is
running
.
The
oil
pump
draws
oil
through
a
pickup
in
the
bot-
tom
of
the
oil
pan,thenforces
it
through
a
replaceable
oil
filter
and
finto
the
engine
oíi
passages
.
On
4-cylinder
engines,
the
oil
pump
is
mounted
to
the
front
engine
cover
.
On
6-cylinder
engines,thechain-driven
oil
pump
is
bolted
to
the
bottom
of
the
cylinder
block
.
A
pressure
relief
valve
limits
the
maximum
system
pres-
sure
.
A
bypass
valve
prevents
the
oil
filter
from
bursting
and
insures
engine
lubrication
should
the
filter
become
plugged
.
See
119
Lubrication
System
for
additional
information
.
ENGINE-GENERAL
100-
5
Various
versions
of
DME
systems
are
usedon
thecars
cov-
MECHANICAL
TROUBLESHOOTING
ered
by
this
manual
.
See
Table
b
.
Each
system
is
highly
adaptive
to
compensate
for
things
suchasengine
wear
and
When
troubleshooting
an
engine
that
fails
to
start
or
runs
vacuum
leaks
.
poorly,
first
check
its
mechanical
condition-particularly
if
the
Warnings
and
Cautions
For
personal
safety,
as
well
asthe
protection
of
sensitive
electronic
components,
the
following
warnings
and
cautions
must
be
adhered
to
during
all
troubleshooting,
maintenance,
and
repairwork
.
WARNING
-
"
The
ignition
system
produces
high
voltages
that
can
be
fatal
.
Avoid
contact
with
exposed
termi-
nals
anduse
extreme
caution
when
working
on
a
car
with
the
ignition
switched
on
or
the
engine
running
.
"
Do
not
touch
or
disconnect
any
high
voltage
ca-
bles
from
the
coil,
distributor,
orspark
plugs
while
the
engine
is
running
or
being
cranked
by
the
starter
"
Connect
and
disconnect
the
engine
manage-
ment
system
wiring
and
test
equipment
leads
only
when
the
ignition
is
switched
off
.
"
Gasoline
is
highly
flammable
and
its
vapors
are
explosive
.
Do
not
smoke
or
work
on
a
car
near
heaters
or
other
fire
hazards
when
diagnosing
and
repairing
fuel
system
problems
.
Have
a
fire
extínguisher
available
in
case
of
an
emergency
.
"
Disconnecting
the
battery
may
erase
fault
code(s)
stored
in
control
module
memory
.
Using
special
BMW
diagnosnnc
equipment,
check
for
fault
codes
prior
to
disconnecting
the
battery
cables
.
If
the
Check
Engine
lightis
illuminated,
see
On-
Board
Diagnostics
(OBD)
forfault
code
infor-
mation
.
If
any
other
system
faults
havebeen
de-tected
(indicated
byan
illuminated
warning
light),
see
an
authorized
BMW
dealer
.
CAUTION-
"
Prior
to
disconnecting
the
battery,
read
the
bat-
tery
disconnection
cautions
gíven
at
the
front
of
this
manual
on
page
viii
.
"
Do
notconnect
any
test
equipment
that
delivers
a
12-volt
power
supply
to
terminal15
(+)
of
the
ignition
coil
.
The
current
flow
may
damage
the
ECM
.
In
general,
connect
test
equipment
only
as
specified
by
BMW,
this
manual,
or
the
equip-
ment
maker
.
"
Do
not
disconnect
the
battery
with
the
engine
running
.
Do
notrunthe
engine
with
any
of
the
sparkplug
wires
disconnected
.
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-
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
.