Page 232 of 1002

Downloaded from www.Manualslib.com manuals search engine
1 16-56
Cylinder Head and Valvetrain
This section covers valve removal and reconditioning, includ-
ing valve guides, seats, springs, and valve stem oil seals.
Valves, leak test
To test the valves for leakage, the cylinder head must be dis-
assembled with camshafts and camshaft carriers removed.
With valve assemblies and spark plugs installed, place the
cylinder head on a workbench with the combustion chamber
facing upward. Fill each combustion chamber with a thin non-
flammable liquid. After fifteen minutes,
check the level of the
fluid. If the fluid level in any cylinder drops, that cylinder is not
sealing properly.
Valves, removing and installing
- Remove cylinder head as described in 113 Cylinder Head
Removal and Installation.
CAUTIOI\C
(M52 TU/M54 engines only) Do not let the hydraulic lifters
fall out as the camshaft carrier is removed. Special suction
cups are available from
BMW to hold the hydraulic lifters in
place during carrier removal.
* Hydraulic cam lifters should be stored m an uprfght po-
sition. If necessary, use a magnetic tool to
aidin remov-
al of the lifters.
- Remove valves using a valve spring compressor.
CAUTIOI\C
Label each valve assembly as it is removed so it can be in-
stalled in its original position.
-
- Remove and discard valve stem oil seals from valve guides.
See Valve stem oil seals later in this section.
- Valve installation is reverse of removal. Remove carbon de- - -
posits from the valves using a wire brush or wire wheel. -
-
Valve specifications are listed in Table c. Valve specifica-
tions.
Page 238 of 1002

Downloaded from www.Manualslib.com manuals search engine
1 17-2
Camshaft Timing Chain
This repair group covers timing chain and VANOS repair
information for the following engines:
M52 (Single VANOS 6-cylinder engine)
M52
TU and M54 (Double VANOS engines)
M62 (Non VANOS
V-8 engine)
NOTE-
The M62 TU V-8 engine with VANOS Variable Camshaft
Timing repair information is not included.
NOTE-
See 100 Engine General for engine code and application
information.
Worn timing chains and sprocltets can lead to noisy operation
and erratic valve timing. Afaulty tensionercan also cause tim-
ing chain noises.
For specific repair procedures, refer to the appropriate repair
group:
020 Maintenance
113 Cylinder Head Removal and Installation
119 Lubrication System
121 Ignition System
170 Radiator and Cooling System
Special tools
Special BMW service tools are needed to perform the service
and repairs procedures covered in this repair group. Many of
these tools are expensive and only available through an au-
thorized BMW dealer. Be sure to read each procedure thor-
oughly before starting a job to determine which special tools
will be necessary.
In addition, Double VANOS system diagnosis can only be
carried out by using BMW specific electronic scan tools, such
as BMW
DISplus, MoDiC or equivalent.
4 Torque wrench wl flex extension
(Tool No. BMW 00
9 250)
Page 243 of 1002

Downloaded from www.Manualslib.com manuals search engine
Camshaff Timing Chain
NOTE-
Mark direction of belt rotation if reusing belt.
- Remove vibration damper mounting bolts and remove vibra-
tion damper and pulley from hub.
NOTE- The M52
6-cylinder engine uses a 2-piece vibration damper
and hub assembly.
4 Install crankshaft holder (BMW special tools 11 2 150
and11 2410).
NOTE
-
Be careful while aligning locator pin hole in special tool 11 2
410 with vibration damper locatorpin.
- While counterholding crankshaft, loosen and remove crank-
shaft center bolt.
CAUTION-
Do not use flywheel locking tool to hold crankshaft stationary
to loosen or tighten crankshaft hub center bolt Use only the
special tools specified, or equivalent hub holding tool.
NOTE- The cranlshaft hub center bolt is torqued to 4
10 Nm
(300
ft-16).
- Remove damper hub and special tools.
4 Install cap (BMW special tool 11 2 383) on end of cranltshaft.
4 Install seal guide (BMW special tool 11 2 385) over end of
crankshaft. Be sure to align tool with keyway on crankshaft
(arrow).
Page 244 of 1002
Downloaded from www.Manualslib.com manuals search engine
1 17-8
Camshaft Timing Chain
4 Install oil seal puller (BMW special tool 11 2 380) and screw
in body of puller until it contacts seal. Tighten center screw to
draw seal out of cover.
4 Coat new seal with oil and position in timing chain cover. Use
BMW special tool
11 3 280 and crankshaft center bolt to draw
seal in flush with timing case cover.
4 Align hub with keyway and tap into place. Insert new center
bolt with washer shoulder
(arrow) facing hub.
CAUTION-
Inspect woodruffl
- Reinstall cranltshaft holder tool.
NOTE-
Be careful while aligning locator pin hole in special tool 1 I 2
410 with vibration damper locator pin.
- While counterholding cranltshaft, tighten crankshaft center
bolt.
Tightening torque Vibration damoer hub
to crankshaft 410 Nm (302 ft-lb)
Page 245 of 1002

Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing Chain
lnstall vibration damper mounting bolts. Note hub locating
dowel (arrow).
Tightening torque
Vibration damper to crankshaft hub
(ME) 22 Nm (16 ft-lb)
- Installation is reverse of removal noting the following:
Installing drive belts. See 020 Maintenance.
Install cooling fan. See 170 Radiator and Cooling Sys-
tem.
Crankshaft oil seal, replacing
(M52 TU and M54 engines)
The crankshafl front seal IS located in the lower timing cover,
behind the
vibrat~on damper.
- Disconnect negative (-) cable from battery.
Disconnecting the battery may erase fault
code(s) storedin
control module memoy Checlc for fault codes using spe-
cial
BMW diagnostic equipment.
Prior to disconnecting the battery, read the battery dis-
connection cautions given in
001 General Cautions
and Warnings.
- Remove splash guard from beneath engine
- Remove engine cooling fan assembly. See 170 Radiator
and Cooling System.
NOTE- Cooling fan nut
(32 mm wrench) has left-hand threads.
- Remove drive belts. See 020 Maintenance
NOTE-
Mark direction of belt rotation if reusing belt.
- Install crankshaft holding tool (BMW special tool 11 8 19011 1
8 200). Make sure tool locks into place in openings in damper
assembly. While counterholding crankshafl with special tool,
remove crankshaft center bolt.
CAUTIOI\C
Do not use flywheel locling tool to hold crankshaft station-
ary to loosen or tighten
cranl(shaft hub center bolt. Use
only the special tools specified, or equivalent hub holding
tool.
Use care when removing
damper/hub assembly, as ~t is
easy to damage the radiator
Page 248 of 1002
Downloaded from www.Manualslib.com manuals search engine
1 Camshaft Timing Chain
< Remove all vibration damper perimeter mounting bolts (ar-
row) and remove vibration damper.
4 Install crankshaft holding tool (BMW special tool 11 2 450)
and remove and discard crankshaft center bolt.
NOJE-
Be careful to align hub locator pin to hole (arrow) in special
tool
11 2 450.
- If needed, use a puller (BMW 11 8 219) to remove hub from
end of crankshaft.
4 Install end cap (BMW special tool 11 2 383) on end of crank-
shaft.
Page 265 of 1002
Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing chain1
Using a drift, drive two locating dowels (arrows) in lower
timing cover toward rear of car.
4 Remove timing cover mounting bolts (arrows).
* Carefully slide cover with water pump forward to remove
CAUTION-
Use care when removing the cover from the cylinder head
gasket If the cover is stuck, use a sharp knife to separate
it from the head gasket.
If cylinder head gasket is damaged, remove cylinder
head and replace head
gaslet. See 113 Cylinder
head and valvetrain.
- Remove timing cover locating dowels by driving them
forward.
- Lift primary chain sprocket off crankshaft sprocket and
remove chain.
Page 275 of 1002
Downloaded from www.Manualslib.com manuals search engine
11 7-39
Camshaft Timing Chain
4 Cover oil hole in VANOS control unit (arrow) with shop towel
to capture oil which will spray when compressed air line is
connected.
- Connect compressed air line to air fitting. Apply air pressure
set to
2 - 8 bar (30 - 110 psi).
4 With compressed air line connected, turn engine clocltwise
using crankshaft center bolt at least two rotations, until cylin-
der
1 is at (TDC) position (intake and exhaust carnshafl lobes
as shown arrows).
Do not rotate engine
countercloclwise to reach the top dead
centerposition. Instead, complete another two complete
Remove sealing plug from bore under starter. Lock
crank-
shafl in TDC position with BMW special tool 11 2 300
(arrow).
-
4 Unscrew and remove threaded studs (arrows) at rear of
cylinder head.