1993 BMW 318i 1996 E36 Workshop Manual

B
mw

3
Series

M3,
3181,3231,3251,
3281

Sedan,
Coupe
and
Convertible

1992,1993,1994,1995,
1996,1997,
1998

Bentley,
Publishers

Cambridge,
Massachusetts

B
-
1
ROBERT
BENTLEY,
INC
.
I
AUTOMOTIVE
PUBLISHERS

Information
that
makes



1734
Massachusetts
Avenue
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difference
o
Cambridge,
MA
02138
USA
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.co
m



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m

WARNING-Important
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time,
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made
tothis
manual
.
A
listing
of
updates
canbe
found
on
the
web
Iat
www
.rb
.com/update
s

Do
not
use
this
manual
unless
you
are
familiar
with
basic
automotive
repair
procedures
and
safe
workshop
practices
.
This
manual
illustrates
the
workshop
procedures
required
for
most
service
work
.
It
is
not
a
substitute
for
fui¡
and
up-to-dateinformation
from
the
vehicie
manufacturer
or
for
proper
training
asan
automotive
technician
.
Note
that
it
is
not
possible
for
us
to
anticipate
al¡
of
the
ways
or
conditions
under
which
vehicles
may
be
serviced
or
to
provide
cautions
as
to
all
of
the
possible
hazards
that
may
result
.

The
vehicie
manufacturer
will
continue
to
issue
service
information
updates
and
parts
retrofits
after
the
editorial
closing
of
this
manual
.
Some
of
those
updates
and
retrofits
will
apply
to
procedures
and
specifications
in
this
manual
.
We
regret
that
we
cannot
supply
updates
to
purchasers
of
this
manual
.

We
haveendeavored
to
ensure
the
accuracy
of
the
information
in
this
manual
.
Please
note,
however,
that
considering
thevast
quantity
and
the
complexity
of
the
service
information
involved,
we
cannot
warrant
the
accuracy
or
completeness
of
the
information
contained
in
this
manual
.

FORTHESE
REASONS,NEITHERTHEPUBLISHER
NORTHE
AUTHOR
MAKES
ANY
WARRANTIES,
EXPRESS
OR
IMPLIED,THATTHE
INFORMATION
IN
THIS
BOOK
IS
FREE
OF
ERRORS
OR
OMISSIONS,
AND
WE
EXPRESSLY
DISCLAIMTHE
IMPLIED
WARRANTIESOF
MERCHANTABILITY
AND
OF
FITNESS
FOR
A
PARTICULAR
PURPOSE,
EVEN
IF
THE
PUBLISHER
OR
AUTHOR
NAVEBEEN
ADVISED
OF
A
PARTICULAR
PURPOSE,
AND
EVEN
IF
A
PARTICULAR
PURPOSE
IS
INDICATED
IN
THE
MANUAL
.
THE
PUBLISHER
AND
AUTHOR
ALSO
DISCLAIM
ALL
LIABILITY
FOR
DIRECT,
INDIRECT,
INCIDENTAL
OR
CONSEQUENTIAL
DAMAGES
THAT
RESULT
FROM
ANYUSE
OF
THE
EXAMPLES,
INSTRUCTIONS
OR
OTHER
INFORMATION
IN
THIS
BOOK
.I
N
NO
EVENTSHALL
OUR
LIABILITY
WHETHER
INTORT,
CONTRACT
OR
OTHERWISE
EXCEEDTHECOST
OFTHIS
MANUAL
.

Your
common
sense
and
good
judgment
are
crucial
to
safe
and
successful
service
work
.
Read
procedures
through
before
starting
them
.
Thinkabout
whether
the
condition
of
your
car,
your
leve¡
of
mechanical
skill,
or
your
leve¡
of
reading
comprehension
might
result
in
or
contribute
in
some
way
to
an
occurrence
which
might
cause
you
injury,
damage
your
car,or
result
in
an
unsafe
repair
.
lf
you
have
doubts
for
these
or
other
reasons
about
your
ability
to
perform
safe
repair
workon
your
car,
have
the
work
done
at
an
authorized
BMW
dealeror
other
qualified
shop
.

Part
numbers
listed
inthis
manual
are
for
identification
purposes
only,
not
for
ordering
.
Always
check
with
your
authorized
BMW
dealer
toverifypart
numbers
and
availability
beforebeginning
service
work
that
may
requíre
new
parts
.

Before
attempting
any
work
on
your
BMW,
read
the
wamings
and
cautions
on
pages
vi¡
and
vi¡¡,
andany
waming
or
caution
that
accompanies
a
procedure
in
the
service
manual
.
Review
the
warnings
and
cautions
on
pages
vi¡
and
viü
each
time
you
prepare
to
workon
your
BMW
.

Special
tools
required
to
perform
certain
service
operations
are
identified
in
the
manual
and
are
recommended
for
use
.
Use
of
tools
other
than
those
recommended
inthis
service
manual
may
be
detrimental
to
the
car's
safe
operation
as
well
as
the
safety
of
the
person
servicing
thecar
.

Copies
of
this
manual
may
be
purchased
from
most
automotiveaccessories
and
parts
dealers
specializing
in
BMW
automobiles,
from
selected
booksellers,
or
directly
from
the
publisher
by
mail
.

The
publisher
encourages
comments
from
the
reader
of
this
manual
.
These
communications
havebeen
and
will
be
carefully
considered
in
the
preparation
of
this
and
other
manuals
.
Please
write
to
Robert
Bentley,
Inc
.,
Publishers
at
the
address
listed
on
the
top
of
this
page
.

This
manual
was
published
byRobert
Bentley,
Inc
.,
Publishers
.
BMW
has
not
reviewed
and
does
not
vouch
forthe
accuracy
of
thetechnical
specifications
and
procedures
described
in
this
manual
.

Libraryof
Congress
Cataloging-in-Publication
Data

BMW
3
SeriesService
ManualM3,
318i,
323i,3251,
328i,
Sedan,
Coupe
and
Convertible
:
1992,
1993,
1994,
1995,
1996,1997,
1998
.
p
.
c
m
.
Includes
index
.
ISBN
0-8376-0326-9
1
.
BMW
3
Series
automobile--Maintenance
and
repair--Handbooks,
manuals,
etc
.
I
.
Robert
Bentley,
inc
.
TL215
.13251356
1999
629
.28'
722--cic21



99-17179
CIP
Bentley
Stock
No
.
B398

Editorial
closing
01/99

0302010099
1098765432

The
paper
used
in
this
publication
is
acidfree
and
meets
the
requirements
of
the
National
Standard
for
Information
Sciences-
Permanence
of
Paper
for
PrintedLibrary
Materials
.
O

©Copyright
1999
Robert
Bentley,
Inc
.

All
rights
reserved
.
All
information
contained
in
this
manual
is
based
onthe
information
available
to
the
publisher
at
the
time
of
editorial
closing
.
The
right
is
reserved
to
make
changes
at
any
time
without
notice
.
No
partof
this
publication
may
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or
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.
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includes
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tables
.
All
rights
reserved
underBerne
andPan-American
Copyright
conventions
.
Manufactured
in
the
UnitedStates
of
America

BMW
SERVICE
MANUUAS
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7
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Service
Manual
:
1988-1994
7351,735iL,
740i,
740iL,
750iL
Robert
Bentley
ISBN
0-8376-0328-5

BMW
3
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Service
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:
1992-1998
M3,
3181,323i,325i,
328i,
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and
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Robert
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ISBN
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:
1996-1998



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ISBN
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RobertBentley
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3181,
325,325e(es),
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RobertBentley
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1989-1995
5251,
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540i
including
Touring
Robert
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ISBN
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BMW
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1982-1988
528e,
5331,
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535is
RobertBentley
ISBN
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ENTHUSIAST
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Complete
Roundel
1969-1998
:30
Years
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ISBN
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A
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WithDeath
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Michael
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ISBN
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The
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of
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Racing,1969-72Michael
Keyser
ISBN
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Mustang
5
.0
Technical
Reference
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Handbook
Al
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ISBN
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Maximum
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Corky
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Tuning
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Per
SchroederISBN
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Automotive
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GTI,
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1985-
The
Design
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Tuning
of
Competition



1992
Gasoline,
Diesel,
and
Turbo
Diesel,
EnginesPhilipH
.
Smith,
6th
editionrevised
by



including
16V
Robert
Bentley
David
N
.
Wenner
ISBN
0-8376-0140-1



ISBN
0-8376-0342-0
Going
Faster
:
The
Skip
BarberRacing



Corrado
Official
Factory
Repair
Manual
:
School
Carl
Lopez
ISBN
0-8376-0227-0



1990-1994
Volkswagen
United
States
9M-f,
Ir-
Win
n
on
Alexander
with
foreword



ISBN
0-8376-0387-0

by
Mark
Martín
ISBN
0-8376-0070-7



Passat
Service
Manual
:
1990-1993,

The
Technique
of
Motor
Racing
Piero



including
Wagon
Volkswagen
United
States

Taruf
fi
with
foreword
by
Juan
Manuel
Fangio



ISBN
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ISBN
0-8376-0228-9



Cabriolet
and
SciroccoService
Manual
:
Race
Car
Aerodynamics



1985-1993,
including
16V
Joseph
Katz
ISBN
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ISBN
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The
Scientific
Design
of
Exhaust
and



VolkswagenFox
Service
Manual
:
1987-
Intake
Systems
Philip
H
.
Smith
and
John
C
.



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including
GL,
GL
Sport
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Morrison
ISBN
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ISBN
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Volkswagen
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Documentation



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Service
Manual
:
Joachim
Kuch
ISBN
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1980-1984
Gasoline
Models,
including

Volkswagen
Beetle
:
Portrait
of
a
Legend



Pickup
Truck,
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and
GTI
Robert

Edwin
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ISBN
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Bentley
ISBN
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Jeep
Owner's
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Moses
Ludel
ISBN
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Eurovan
Official
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Manual
:



MANUUAS

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Inspection/Maintenance
(I/M)
Emission
Test
Handbook
:1980-1997
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of
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Rabbit,
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Service
Manual
:
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including
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RobertBentley
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Super
Beetle,
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Ghia
Official
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Type1
:1970-1979Volkswagen
United
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ISBN
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and
Karmann
Ghia
Official
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Manual
Type1
:1966-1969
Volkswagen
United
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ISBN
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Harley-Davidson
Evolution
V
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Owner's
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Ludel
ISBN
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Audi
100,
A6
Official
Factory
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Manual
:
1992-1997,
including
S4,
S6,
quattro
and
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models
.
Toyota
Truck
&
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Cruiser
Owner's



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of
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.
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BibleTM
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Ludel
ISBN
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80,
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SERVICE
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The
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Denis
Jenkinson



Factory
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Manual
:
1988-1992
ISBN
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including
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Audi
of
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Unbeatable
BMW
:
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Engineering
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100,
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Official
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JeremyWalton
ISBN
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.
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5000CS
Official
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BMW
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Control
:
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Charles
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.
Probst,
SAE



Repair
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:
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Gasoline,
Car
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of
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ISBN
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Gasoline
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VOLKSWAGEN
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:
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RobertBentley
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Official
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:
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and
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Turbo
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GTI,
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:



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Robert
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OFFICIALSERVICE

1992-1999
Volkswagen
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19851993
RobertBentl



ISBN
0837603129
-ey---

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8
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:
1981-1988
Robert
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Passat
Official
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:



VOLVO
SERVICE
MANUAL
1995-1997
Volkswagen
of
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240
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:
1983-1993
ISBN
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Robert
Bentley
ISBN
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Robert
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automobile
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.
Please
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Robert
Bentley,
Inc
.,
Publishers,
at
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MA
02138,
visit
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://www
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.

100-2
ENGINE-GENERAL

Cylinder
Head
and
Valvetrain

The
aluminum
cylinder
head
uses
chain-driven
double
overhead
camshafts
and
four
valves
per
cylinder
.
See
Fig
.
1
.

The
cylinder
head
employs
a
crossflow
design
for
greater

power
and
efficiency
.
Intake
air
enters
the
combustion
cham-

ber
from
one
side
while
exhaust
gasses
exit
from
the
other
.

Oílways
in
the
head
provide
lubrication
for
the
camshafts)
and
valvetrain
.

Fig
.
1
.



M52
twin-cam,
4-valve-per-cylinder
engine
with
hydraulíc
lift-
ers
.

On
all
engines
exceptthe
M44
engine,
valveclearance
is
by
seif-adjusting
hydraulic
lifters
.
On
M44
engines,
instead
of
hy-

draulic
lifters,
hydraulic
pedestaisare
used
in
combination
with
roller
rocker
arms
to
actuate
the
valves
.
Hydraulic
pedes-
tals
have
the
same
function
as
hydraulic
lifters,
which
ís
to
maintain
zero
valve
clearance,
reduce
valve
noise,
and
elimí-
nate
routíne
adjustment
.
See
Fig
.
2
.

VANOS
(Variable
Valve
Timing)

GENERAL

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

4

Fig
.
2
.



Cross
sectionof
M44
twin-cam,
4-valve-per-cylinder
head
.
Note
function
of
hydraulíc
pedestal
in
combination
with
rock-er
arm
(with
roller
bearing
for
reduced
friction)
.

The
main
components
of
the
VANOS
system
arethe
piston

housing
with
integral
spool
valve
and
solenoid,
and
the
modi-

fied
intake
camshaft
and
sprocket
assembly
.
See
Fig
.
3
.

1993
and
later
6-cylinder
engines
are
equipped
with
a
vari-



B11001

able
intake
valve
timing
system,
known
as
VANOS
(from
the
German
words
Variable
Nockenwellen
Steuerung)
.
The



Fig
.
3
.
VANOS
(variable
intake
valve
timing)
systemusedon
M52
en-
VANOS
system
electro-hydraulically
adjusts
intake
valve
tim-



gine
.
When
solenoid
is
actuated,
oíl
pressure
is
directed
to
ingfor
enhanced
mid-range
performance
.
The
VANOS
sys-



front
side
of
gear
cup
piston
.
This
forces
gear
cup
finto
camtem
is
controlled
by
the
engine
control
module
(ECM),
using



shaft
to
advance
intake
valve
timing
.
enginespeed,engine
load
and
engine
temperature
asthe
pri-
mary
inputs
.



When
the
engine
is
running,
the
piston
housing
is
supplied
with
pressurized
engine
oil
víathe
solenoid-actuatedspool
At
low
speeds,
the
intake
valves
open
late
to
ensure
smooth



valve
.
Depending
on
the
position
of
the
spool
valve,
oil
isdi
engine
operation
.
At
mid-rangespeeds,
thevalves
open
early



rected
to
either
the
front
or
back
side
of
the
gear
cup
piston
.
(valvetiming
advanced,
VANOS
actuated)
for
increased
torque,
improved
driveability,
and
reduced
emissions
.
And
at



When
the
solenoid
isin
the
off
position,
engine
oíl
is
direct-
high
speeds,
the
valves
again
open
late
for
optimum
power



ed
to
the
back
side
of
the
piston
.
This
holds
the
gear
cup
for-
and
performance
.



ward
and
valve
timing
is
maintained
at
the
normal
"late"
position
.
When
the
solenoid
is
energized,
the
spoolvalve
is
moved
forward
and
oil
pressure
is
directed
to
the
front
side
of
the
piston
.
This
in
turn
moves
thegear
cup
further
into
the

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

116-
1
0



CYLINDER
HEADAND
VALVETRAIN

NOTE-

When
checking
a
cam
follower,
make
sure
the
corre-
sponding
camshaft
lobe
ís
facing
up
so
that
there
is
no
valve
spring
pressure
on
the
follower
.

4
.
To
replace
a
cam
follower,
remove
appropriate
cam-

shaft
.
Refer
to
camshaft
removal
procedures
given
ear-
lier
.

5
.
Once
camshaft
is
out
of
way,
withdraw
faulty
cam
fol-

lower
and
replace
with
new
one
.
Inspect
cam
follower

bores
for
wear
and
scoring
.

6
.
Camshaft,
timing
chain
and
cylinder
head
cover
reas-
sembly
is
reverse
of
disassembly
.

Tightening
Torques

"
Camshaft
bearing
caps
to
cylinder
head

M7
....
.
..
.
......
.
.....
...
.
..
.
15
Nm
(11
ft-Ib)

"
Cylinder
head
cover
to
cylinder
headltiming
chain
cover
M6
....
.
..
.
.
.
..........
...
.
.
..
10
Nm
(89
in-lb)

"
Timing
chain
hydraulic
tensioner
to

cylinder
head-see
117
Camshaft
Timing
Chain

"
Timing
chain
sprocket
to
camshaft

flange
(M6)-see
117
Camshaft
Timing
Chain

CYLINDER
HEAD
AND
VALVETRAIN,
RECONDITIONING

Table
c
.
Valve
Guide
Specifications

Fig
.
16
.
Valveguide
wear
being
checked
with
dial
indicator
.
Insert
new
valve
until
stem
end
is
flush
with
end
of
guide(white
arrow)
.
See
Table
c
for
wear
limits
.

NOTE-

Valve
guides



"
Intemational
Organization
for
Standardization
(ASO)
tolerance
classes
are
Gsted
in
Table
c
.
ISO
allowanc

BMW
does
notsupply
valve
guides
as
replacement
parts
.
If



esare
based
on
nominal
sizes
and
should
beused
to

a
valve
guide
is
excessively
worn,
it
should
be
reamed
to
ac-



determine
proper
fit
.
Most
machine
shops
should

cept
oversized
valve
stems
.
Valve
guide
specifications
are



have
thís
informationavailable

listed
in
Table
c
.



"
Replacement
valve
guides
may
be
available
through
aftermarket
suppliers
.
Valve
guide
replacement
re-
Valve
guides
should
be
checked
for
wear
using
a
new



quires
specíal
tools
and
a
press
.
It
is
also
necessary
valve
.
See
Fig
.
16
.
Be
sure
to
thoroughly
inspect
the
cylinder



to
heat
the
cylinder
head
and
chile
the
valve
guides

head
to
ensure
that
it
can
be
reused
before
reworking
the



when
replacing
the
guides
.

guides
.
"
BMW
suppllesoversize
valves
.
Sea
Valves
for
addi-
tional
information
.

Specifications



M42
engine



M421M44
engines



M50
engine



M50,M52,
S50
US,
S52

~
(1992)



~
(1993-1998)



~
(1992)



~
US
engines
(1993-1998)

Valve
guide
wear,
maximum
(valve
tílt
clearance
measured
with
new
valve)



0
.5
mm
(0
.020
in)



0
.5
mm
(0
.020
in)



0
.5
mm
(0
.020
in)



0
.5
mm
(0
.020
in)

Valveguide
inside
diameter,
installed
(tolerance
per
ISO
allowance
H7)
Standard



7
.0
mm
(0
.276
in)



6
.0
mm
(0
.236
in)



7
.0
mm
(0.276
in)



6
.0
mm
(0
.236
in)
Oversize
1



7
.1
mm
(0
.279
in)



6
.1
mm
(0
.240
in)



7
.1
mm
(0.279
in)



6
.1
mm
(0
.240
in)
Oversize
2



7
.2
mm
(0
.283
in)



6
.2
mm
(0
.244
in)



7
.2
mm
(0
.283
in)



6
.2
mm
(0
.244
in)

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

116-12



CYLINDER
HEADAND
VALVETRAIN

Valve
Seats



Valve
Springs

The
valve
seats
should
be
resurfaced
whenever
new
valves



The
valvesprings
should
be
checked
for
fatigue
.
To
quickly
or
valve
guides
are
installed
.
Cutters
are
required
to
resurface



check
the
springs,
line
them
up
in
a
row
.
Place
a
straight
edge
the
seats
.
Always
check
thevalves
for
leaks
after
recondition-



across
thetop
of
the
springs
.
Any
spring
that
is
significantly

ing
a
valve
seat
as
described
above
.
Table
e
lists
valve
seat



shorter
than
theothers
is
worn
and
should
be
replaced
.

dimensions
.

NOTE-
NOTE-



Valve
spring
specifications
and
wear
límits
arenot
Standard
size
replacement
valve
seats
are
not
avail-



available
from
BMW
.
ablefrom
BMW
.
Replacement
valve
seats
are
only
available
from
BMW
in
0
.4
mm
oversize
(oversized
in
both
height
and
diameter)
.
The
manufacturer
does
not
provide
specífications
for
valve
seat
replacement
for
the
enginescovered
by
this
manual
.

Table
e
.
Valve
Seat
Dimensions

"Y

Valve
seat
outside
dia
.
(B)

CYLINDER
HEAD
AND
VALVETRAIN,
RECONDITIONING

60
°
yl
1
B11110c

Specification



M42
engine



M42
engine



M44
engine



M50
engine



M501M52
engines



S50USIS52US
(1992)



(
(1993-1995)



I
(1996-1998)



(1992)



I
(1993-1998)



I
engines
(1995-
1998)

Valve
seat



45°



451



145°



145°



(
45°



145°
angle

Correction



1
15°



15°



115°



(
15°



15°



15
angle,
outside

Correction
60°



60°



I60°



60°



I60°



I60°
angle,
inside

Va
lve
seat
width
(A)
intake



1
1
.65
±0
.25
mm



1
1.65
±0
.25
mm



1
1
.65
t
0
.25
mm



1
1
.4
-1
.9
mm



1
1
.65
±0
.25
mm



1
1
.65
±
0
.25
mm
(0
.065
+0
.014
in)



I
(0.065
t
0
.014
in)



(0
.065
:E
0
.014
in)



(0
.055-0.075
in)



(0
.065
t
0
.014
in)



l(0
.065t0
.014
in)
____
___
exhaust



12
.0
±0
.25
mm



12
.0
t
0
.25
mm



1
1
.65
t
0
.25
mm



1
1
.4
-
1
.9
mm



11
.65
±
0
.25
mm



1
1
.65
:t
0
.25
mm
(0.079
±
0
.014
in)



1
(0
.079
t0
.014
in)



1
(0
.065
±
0
.014
in)



1
(0
.055-0.075
in)



1
(0
.065
t
0
.014
in)



1
(0.065
t0
.014
in)

intake



32
.4
mm
(1
.276
in)



32
.4
mm
(1
.276m)



32
.4
mm
(1
.276
in)



32
.4
mm
(1
.276
in)



32
.4
mm
(1
.276
in)



29
.4
mm
(1
.157
in)

exhaust



30
.1
mm
(1
.185
in)



30
.1
mm
(1
.185
in)



30
.1
mm
(1
.185
in)



30
.1
mm
(1
.185
in)



29
.4
mm
(1
.157
in)



26
.4
mm
(1
.039
in)

117-
1
0



CAMSHAFT
TIMING
CHAIN

21
.
On
1993
and
lates
engines
:
Remove
access
plugs
from



24
.
On
1993
and
later
engines
:

VANOS
control
unit
in
front
of
exhaust
camshaft



"
Remove
VANOS
control
unit
as
described
laterinthis
sprocket
.
Remove
4
bolts
from
exhaust
camshaft



repair
group
.
sprocket
(useTono
El0
socket)
.
See
Fig
.
26
.



"
Remove
intake
camshaft
sprocket
mounting
nuts
.

"
Remove
intake
and
exhaust
sprockets
together
with

secondary
chain
.
Note
location
of
thrust
washers
and

spring
plate
(where
applicable)
on
intake
sprocket
.

Fig
.
26
.
Exhaust
camshaftmounting
bolts
(arrows)
.

CAMSHAFT
TIMING
CHAINS,
6-CYLINDER

0013056

22
.
Depress
secondary
timing
chain
tensiones
and
lock

down
by
inserting
stiff
wire
into
the
openings
in
rear
of
tensioner
.
See
Fig
.
27
.

Fig
.
27
.
Secondary
timing
chaintensioner
being
locked
down
on
M50
engine
.
Press
tensioner
downand
insert
locking
wire
through
holes(arrows)
.
Tensioner
on
M52/S52
US
engines
vary
slight-

23
.
Remove
secondary
chain
tensioner
and
lift
out
primary
chain
guide
.

NOTE-

Hold
the
camshaft
stationary
(at
hex
on
camshaft)
when
loosening
ortightening
sprocket
mounting
boits
.

CAUTION-

The
crankshaft
must
not
be
allowed
to
rotate
once
the
timing
chain
is
removed
.
The
pistons
can
con-
tact
the
valves
.

25
.
On
1992
engines
:

"
Remove
from
intake
and
exhaust
sprocket
mounting

bolts
.
"
Remove
sprockets
together
with
secondary
chain
.

26
.
Remove
bolts
holding
lower
timing
chain
cover
to
cylin-

der
head
(use
Torx
E8
socket)
.
See
Fig
.
28
.

MR111:
R

Fig
.
28
.
Cylinderhead-to-timingchain
covermounting
bolts
(arrows)
.

27
.
Using
a
drift,
drive
two
locatiog
dowels
in
left
and
right

sides
of
lower
timing
chaincover
toward
rear
of
car
.
Re-
move
covermounting
boits
and
carefully
lift
cover
off
.
See
Fig
.
29
.

CA
UTION-

Use
care
when
removing
the
cover
from
the
cylin-
der
head
gasket
.
If
the
cover
is
stuck,
useasharp
knife
to
separate
it
from
the
head
gasket
.

117-
1
2



CAMSHAFT
TIMING
CHAIN

4
.
Mount
primary
timing
chain
sprocket
to
primary
chain

so
that
arrowon
sprocket
faces
up
.
Mount
sprocket
to

camshaftso
that
tapped
holes
in
camshaftare
on
left

side
of
elongated
holes
in
sprocket
.
See
Fig
.
31
.

NOTE-

On
engines
built
beginning
from
March
1995,
the
VANOS
intake
cam
sprocket
assembly
was
updated
to
ínclude
a
spring
plate
and
two
thrust
washers
.
See
Fig
.

Fig
.
31
.
Primary
timing
chain
sprocket
correctly
alignedto
exhaust



33
.
camshaft
.
Elongated
sprocket
holes
should
be
aligned
to
left
side
of
threaded
camshaft
holes
.

5
.
On
1993
and
later
engines
:Install
BMW
special
tool
no
.
11-3
390
into
primary
timíng
chain
tensionersleeve
.
Thread
toolin
finger
tight
until
slack
is
removed
from

chain
.

"
Check
that
elongatedholes
in
primary
sprocket
are

centered
to
bolt
holes
in
camshaft
and
chain
is
free
of
slack
.

NOTE-

BMW
special
tool
no
.
11
3
390
ís
a
dummy
primary
chaín
tensioner
and
simulatesthe
function
of
the
hy-
draulic
tensíoner
.

7
.
Install
cylinder
identification
trigger
píate
to
front
of
in-

take
camshaft
.
On
1993
and
later
engines,
instanthrust
washer
tofrontof
intake
camshaft
.

CAMSHAFT
TIMING
CHAINS,
6-CYLINDER

B11136

Fig
.
32
.
Secondary
chain
sprockets
being
installed
.
Attach
sprockets
with
arrows
pointing
up
and
elongated
holes
centered
to
threaded
holes
in
shaft
flange
.

6
.
Install
primary
timing
chainguide
and
secondary
chain
tensioner
.
Tighten
mounting
bolts
.
(Tensioner
remains



Fig
.
33
.
VANOS
spring
plate
and
thrust
washers
on
engines
built
3/95locked
down
for
now
.)



and
later
.

10
.
On
1993
and
later
cars,
tighten
nuts
at
intake
camshaft
sprocket
.

8
.
Insta¡¡
secondary
chainsprockets
and
chain
asan
as-
sembly
so
that
arrows
on
sprockets
are
pointing
up
.



Tightening
Torque
(1996
and
later)

Centermounting
holes
in
sprockets
tobolt
holes
in



"
Intake
camshaft
sprocket
nut
camshafts
.
See
Fig
.
32
.



to
stud
(M6)
.............
.10t
1
Nm
(89
±9
in-lb)

9
.
On
1993
and
later
engines
:
Insta¡¡
thrust
washers
and
spring
plate
(where
applicable)
to
intake
cam
sprocket
.



11
.
On
1992
engines
:
Insta¡¡
primary
chain
tensioner
so
that
cutout
in
tensioner
piston
engages
chain
rail
.
See
Fig
.
34
.
Check
that
chain
is
free
of
slack
.