1992 BMW 318i 001

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
.

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
.
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

116-2



CYLINDER
HEADAND
VALVETRAIN

3
.
Remove
timing
chain
sprockets
and
timing
chains
from



7
.
Slowly
release
pressure
oncamshaft
bearing
capsby
camshafts
.
Remove
upper
timing
chain
guidefrom
cyl-



turningeccentric
shaft
.
Remove
bearing
caps
and

inder
head
.
See117
Camshaft
Timing
Chain
.



camshaft
.
Repeat
procedureon
remaining
camshaft
.

NOTE-

It
is
not
necessary
lo
remove
the
lower
timing
chain
cover
.

4
.
Remove
spark
plugs
and
instaf
BMW
special
tool
11
3

260
to
cylinder
head
.
Tighten
tool
retaining
bolts
in

spark
plug
holes
.
Do
not
over-tighten
bolts
.
See
Fig
.
1
.

6
.
Remove
bearing
cap
mounting
nuts
.

0013033

5
.
Turn
eccentric
shaft
on
special
tool
until
pressure
is
ap-

plied
to
camshaft
bearing
caps
.
See
Fig
.
2
.

Fig
.
2
.



Special
tool
(eccentric
shaft)
being
turned
to
apply
pressure
to
camshaft
bearing
caps
.

CYLINDER
HEAD,
DISASSEMBLYAND
ASSEMBLY

CAUTION-

Camshaft
bearing
caps
mustbe
reinstalled
intheir
original
locations
.

NOTE-

"
The
camshaft
bearing
caps
are
coded
wíth
a
letter
anda
number
.
Forexample,
"Al
"ís
the
exhaust
cam-

shaft
bearing
cap
at
the
front
of
the
engíne,
and
"El"
is
the
intake
camshaft
bearing
cap
at
the
front
of
the
engine
.

"
Camshafts
are
stamped
with
a
code
letter-`E"
for
the
intakeside
and
`A"forthe
exhaust
side
.

"
"E"
isforEinlal3,
(German
for
íntake)
and
A"
isfor
Auspuff,
(German
for
exhaust)
.

"
The
front
of
the
engine
is
at
the
front
of
thecar
.

8
.
Camshaft
installation
is
reverse
of
removal,noting
the

following
:

"
Prior
to
installation,
check
al¡
components
for
wear
as

described
below
underCylinder
Head
and
Va¡-

Fig
.1
.



Special
BMW
tool
no
.
11
3
260
.
Tool
mounting
bolts
(arrows)



vetrain,
Reconditioning
.

thread
into
spark
plug
holes
.



"
Crankshaft
must
be
at
least
45°
away
from
TDC
before

installing
camshafts
to
cylinder
head
.

"
Lubricate
camshafts
prior
to
installation
.

Tightening
Torque



"
Install
camshafts
into
cylinder
head
with
lobes
for
cyl-

"
BMW
special
tool
11
1
260



inder
no
.
1
pointing
up
and
towards
each
other
.

to
cylinder
head
.
...
.
.
...........
23
Nm
(17
ft-Ib)



"
After
installing
camshafts),observe
specified
waiting

time
for
hydraulic
cam
followers
to
fully
compress
be-
fore
bringing
crankshaft
back
to
TDC
.

CYLINDER
HEAD
AND
VALVETRAIN,

RECONDITIONING

Thís
section
provides
the
specifications
and
special
recon-
ditioning
information
necessary
to
repair
the
cylinder
heads

covered
by
this
manual
.

If
machine
shop
services
are
not
readily
available,
one
al-

ternative
is
to
install
a
remanufactured
cylinder
head
froman

authorized
BMW
dealer
.

Cylinder
head

NOTE-

When
replacing
the
cylinder
headon
engines
with
re-
movablecamshaft
carriers,
be
sure
to
check
the
cam-
shaft
carrier
bearing
surfaces
for
warpage
.

4-cylinder



1
140
.0
mm
(5
.512
in)



1
139
.55
mm
(5
.494
in)

6-cylinder



1



140
.0
mm
(5
.512
in)



1



139
.7
mm
(5
.500
in)

CYLINDER
HEAD
AND
VALVETRAIN



116-
7

A

The
disassembled
cylinder
head
should
be
inspected
for



Fig
.
9
.



Front
víew
of
cylinder
head
showing
minimum
resurfacing
di-

warpage
and
cracks
.
Check
the
valve
guides
and
valveseats



mension
(A)
.

for
wear
before
machining
a
warped
head
.
Always
decarbon-

ize
and
clean
the
head
before
inspectiog
it
.
A
high-quality



Camshaft

straíght
edge
can
be
used
to
check
for
warpage
.
Camshaft
wear
is
usually
caused
by
insufficient
lubrication
.

Visually
inspect
the
cylinder
head
for
cracks
.
If
acracked



Visually
inspect
the
camshaft
lobes
and
journals
for
wear
.

cylinder
head
is
suspected
and
no
cracks
are
detected



Camshaftwear
specifications
are
given
in
Table
b
.

through
the
visual
inspection,
have
the
head
further
tested
for

cracks
byan
authorized
BMW
dealer
.
A
cracked
cylinder
head



Table
b
.
Camshaft
Specifications

must
be
replaced
.



4-cylinder
engines

Axialplay
M42
engine



0
.065-0
.150
mm
(0
.0025-0
.0059
in)

M44
engine



0
.065-0
.150
mm
(0
.0025-0
.0059
in)

Radial
play(Plastigage)



0
.020-0.061
mm
(0
.0008-0
.0024
in)
M42
engine
M44
engine



0
.040-0
.082
mm
(0
.0016-0
.0032
in)

6-cylinder
engines
A
warped
cylinder
head
can
be
machined
provided
no



Axial
pla
y
more
than
0
.3
mm
(0
.012
in)
of
material
is
removed
.
If
further



All



0
.020-0.054
mm
(0
.0008-0
.0021
in)

machining
is
required,
the
head
should
be
replaced
.
Remov-



Radial
play(Plastigage)
0
.150-0.330
mm
(0
.006-0.013
in)
ing
more
than
this
amount
will
reduce
the
size
of
the
combus-



All

tion
chamber
and
adversely
affect
engine
performance
.
A
0
.3

mm
thicker
gasket
is
available
from
an
authorized
BMW
parts

department
for
machined
heads
.



NOTE-

-
On
M44
engines,
check
the
oil
sprayer
tube
in
the
top
Before
machining
the
head
to
correct
for
warpage,
measure



of
the
cylinder
head
coverand
the
tubesea¡
in
the
cyl-

the
total
height(thicknessof
the
cylinder
head)
.
See
Fig
.
9
.



inderhead
.Acloggedsprayertubeoradefectiveseal

Minimum
height
specifications
are
given
in
Table
a
.



will
reduce
oil
flowto
the
camshaft
.
See
Fig
.
10
.

-
If
the
camshaft
is
being
replaced
due
to
cam
lobe
Table
a
.
Cylinder
Head
Height



wear,
the
corresponding
rockerarms
orcam
followers

Engine



New



Minimum
height



shouId
also
be
replaced
to
avofd
damaglng
the
new

(dimension
A)



camshaft
.

CYLINDER
HEAD
AND
VALVETRAIN,
RECONDITIONING

116-
8



CYLINDER
HEAD
AND
VALVETRAIN

0012502

Fig
.
10
.
Location
of
camshaft
oil
sprayer
tube
sea¡
in
M44
cylinder
head
(arrow)
.

Hydraulic
valve
adjusters,

checking
and
replacing
(M44
engine)

The
M44
engine
uses
hydraulic
valveadjusters
(HVA)
to
keep
valve
clearances
within
a
limited
working
range
.
See
Fig
.
11
.
HVAs
are
sealed
units
and
require
no
maintenance
.

1
.
Camshafts
2
.
Rocker
arms
3
.
Hydraulic
valve
adjusters
(HVA)
4
.
Valve
and
conical
valve
spring

Fig
.
11
.
Cutaway
view
of
M44
cylinder
head
.

Under
some
circumstances,
such
as
a
cold
start,
thehy-
draulic
units
may
become
noisy
.
Hydraulic
valve
adjusternoise
is
usually
ahigh-pitched
tapping
or
chattering
noise
.
In
most
instances,
this
is
consídered
normal
aslong
as
the
noise
goes
away
in
a
few
minutes
(maximum20
minutes)
.
If
thenoise
does
not
go
away,
either
the
hydraulic
unit
is
faulty
orthe
oil
pressure
tothe
adjuster(s)
is
low
.

CYLINDER
HEAD
AND
VALVETRAIN,
RECONDITIONING

NOTE-

8efore
checking
valveadjusters,
make
sure
engine
oil
is
fresh
and
at
proper
level
.

1
.
Run
engine
until
it
reaches
normal
operating
tempera-

ture
.

2
.
Turn
engine
off
and
remove
top
engine
cover,
spark

plugs,
and
cylinder
head
cover
.
See
113
Cylinder
Head
Removal
and
Installation
.

3
.
Use
a
plastic
or
wooden
stick
to
press
down
on
top
of

rocker
armend
(side
away
from
camshaft)
.
If
any
play
can
be
detected,the
HVA
is
faulty
and
should
be
re-

placed
.

NOTE-

When
checking
the
HVA,
make
sure
the
camshaft
lobe
is
facing
upso
that
there
is
no
valve
spring
pressure
on
the
adjuster
.

4
.
To
remove
an
HVA,
turn
engine
over
until
camshaft
lobe

points
straight
up
.
Using
BMW
special
tool
no
.
11
5
130,
depress
valvespring
and
remove
rocker
arm
from
under
camshaft
.
See
Fig
.
12
.

Fig
.
12
.
BMW
special
tool
no
.
115
130
(arrow)
being
used
to
depress
valve
stem
to
remove
rocker
arm
.

WARNING
-

Removed
rocker
armsmustbe
reinstalled
in
the
same
locations
.

Valves

Valve
specifications
are
listed
in
Table
d
.
Remove
carbon

deposits
from
thevalves
using
a
wire
brush
or
wire
wheel
.

Specification



M42
engine



M42IM44
engines



M50
engine



M50,
M52
engines



S50
USIS52
US
(1992)



(1993-1998)



(1992)



(1993-1998)



I
engine
(1995-1998)

Valve
head
dia
.
Intake



133
.0
mm
(1
.299
in)



133
.0
mm
(1
.299
in)



33
.0
mm
(1
.299
in)



33
.0
mm
(1
.299
in)



130
.0
mm
(1
.181
in)
Exhaust



30
.5
mm
(1
.201
in)



30
.5
mm
(1
.201
in)



30
.5
mm
(1
.201
in)



~
30
.5
mm
(1
.201
in)



27
.0
mm
(1
.063
in)

Valve
stem
dia
.
Standard
Intake



6
.975-0
.015
mm



5
.975-0
.015
mm



6
.975-0
.015
mm



5
.975-0
.015
mm



5
.975-0015
mm
(0
.2746-00006
in)



(0
.2352-00006
in)



(0
.2746-00006
in)



(0
.2352-00006
in)



(0
.2352
-
00006
in)
Exhaust



6
.960-0015
mm



5
.960-0
.015
mm



6
.960
--0
.015
mm



5
.960
-0
.015
mm



5
.960-0
.015
mm
(0
.2740-00006
in)



(0
.2345-0
.0006
in)



(0
.2740--0
.0006
in)



(0
.2345-0
.0006
in)



(0
.2345-0
.0006
in)

Intake



7
.075-0
.015
mm



6
.075-0
.015
mm



7
.075-0
.015
mm



6
.075-0
.015
mm



6
.075-0
.015
mm
(0
.2785-00006
in)



(0
.2392-0
.0006
in)



(0
.2785-00006
in)



(0
.2392
-
00006
in)



(0
.2392-00006
in)
Exhaust



7
.060-0015
mm



6
.060-0015
mm



7
.060-0
.015
mm



6
.060-0015
mm



6
.060-0015
mm
(0
.
2779-0
.0006
in)



(0
.2386-00006
in)



(0
.2779-00006
in)



(0
.2386-00006
in)



(0
.2386-00006
in)

Oversize
2
Intake



7
.175-0
.015
mm



6
.175-0
.015
mm



7
.175-0
.015
mm



6
.175-0
.015
mm



6
.175-0
.015
mm
(0
.2825-00006
in)



(0
.2431-00006
in)



(0
.2825-00006
in)



(0
.2431--0
.0006
in)



(0
.2431-00006
in)
Exhaust



7
.160-0015
mm



6
.160-0015
mm



7
.160-0
.015
mm



6
.160-0015
mm



6
.160-0-015
mm
(0
.2819
-
00006
i
n
)



(0
.2425-00006
in)



(0
.2819-00006
in)



(0
.2425-00006
in)



(0
.2425-00006
in)

Valves,
leak
test
NOTE-

BMW
speclal
tools
are
available
to
remove
the
valve
To
test
thevalves
for
leakage,
the
camshafts
and
camshaft



stem
oil
seals
.
As
an
alternative,
standard
valvesea¡

carriers
(where
applicable)
should
first
be
removed
.
Instali
the



removal
tools
are
available
from
most
automotive
parts

valve
assemblies
and
the
spark
plugs
in
each
cylinder
.
Place



stores
.
See
Flg
.
17
.

the
cylinder
head
on
a
workbench
with
the
combustion
cham-

ber
facing
upward
.
Fill
each
combustion
chamber
with
a
thin

non-flammable
liquid,
suchas
a
parts
cleaning
fluid
.
After
fif-

teenminutes,
check
the
leve¡
of
the
fluid
.
If
the
fluid
level
in
any

cylinder
drops,
thatcylinder
is
not
sealing
properly
.

Valve
Stem
Oil
Seals

The
purpose
of
the
valve
stem
oil
sea¡
is
to
prevent
excess

oil
from
entering
the
combustion
chamber
.
The
sign
offautty

valve
stem
oil
seals
is
excessive
oil
consumption
and
smoke

from
the
exhaust
immediately
after
starting
and
during
decel-

erat¡on

NOTE-

Valve
stem
oil
seals
should
not
be
reused
.
ff
valves
are

removed,
new
valve
stem
oil
seals
should
be
installed
.

Valve
stem
oil
sea¡
replacement
requires
that
the
cylinder

head
be
disassembled
and
thevalves
removed
as
described

above
under
Valves,
removing
and
installing
.

CYLINDER
HEAD
AND
VALVETRAIN



116-
11

Table
d
.
Valve
Specifications

Fig
.
17
.
Valve
stem
oil
sea¡
being
removed
from
valve
guide
.

Lubricate
the
new
seals
and
insta¡]
them
using
hand
pres-

sure
only
.
Be
sure
to
install
the
valve
spring
seat(s)
before
in-

stalling
the
sea¡
.

CYLINDER
HEAD
AND
VALVETRAIN,
RECONDITIONING