Page 134 of 1002

Downloaded from www.Manualslib.com manuals search engine
11 3-40
I Cylinder Head Removal and Installation
Lubricate camshafts, camshaft carriers, bearing caps, hy-
draulic lifters, friction washers, splined shafts and spline hubs
with assembly lubricant before installation.
4 Check that two cylinder head aligning sleeves (arrows) are
correctly positioned in block and are not damaged.
- Apply elastic sealing compound Three Bond 1209 8 to cor-
ner joints on cylinder block to timing chain cover.
- Place new cylinder head gasket on cylinder block.
NOTE-
The word "OBEN" or "TOP printed on the gasket, should
face up. The cylinder headgaslet will fit correctly in only one
orientation.
- Set cylinder head in position, guiding primary chain through
cylinder head opening.
CAUJION-
Make sure the crankshaft, which had been rotated approxi-
mately 30" opposite the direction of engine rotation from
TDC, is still in thatposition before lowering the cylinder head
into position. All pistons must be out of TDC position to pre-
vent
valve/piston interference when the camshafts are in-
stalled.
- Lightly lubricate new cylinder head bolts and washers with
oil. Install bolts and washers finger tight. Install cylinder head
to lower timing chain cover bolts finger tight.
NOJE-
Cylinder head bolts should not be reused. They are
stretch-type bolts and must be replaced whenever loos-
ened.
* Aluminum cylinder blocls use different length cylinder
head bolts and torque values than cast iron blocks.
Check that all washers for
Nle head bolts are in place be-
fore installing the bolts. Some of the washers may be
staked to the cylinder head.
I 12 10 4 2 6 8 141 Tighten cylinder head bolts in correct sequence (1-14)
CA U TIOW-
The bolts should be tightened in three stages as listed below
The final stages require the use of a BMW special tool
11 2
110 or a suitable protractor to tighten the bolts to a specified
torque angle.
Page 156 of 1002
Downloaded from www.Manualslib.com manuals search engine
. .- --
[Cylinder ~ead Removal and Installation
4 Remove cylinder head cover fasteners (arrows) and remove
covers from left and right cylinder heads.
4 Remove oil distribution tubes from camshaft bearing caps
from left and right cylinder heads.
4 Using crankshaft center bolt, turn crankshaft clockwise until
number one cylinder (passenger side front cylinder) is in
TDC overlap position (arrow).
NO JE -
Number one cylinder is at valve overlap when both the intake
and exhaust valves are starting to open (camshaft lobes fac-
ing down).
4 Working at right cylinder head, loosen three accessible cam-
shaft sprocltet fasteners (arrows) on both intake and exhaust
camshafts approximately
'I2 turn.
To prevent valve to piston contact when loosening camshaft
sprocket fasteners, counterhold camshaft with
27 mm open-
end wrench.
If necessary, grind outerside of wrench jaws to
prevent damaging cylinder head.
Page 178 of 1002

Downloaded from www.Manualslib.com manuals search engine
This group covers cylinder head and valvetrain service and
repair. Some of the repair procedures described here require
that the cylinder head first be removed as described in
113
Cylinder Head Removal and Installation.
NOTE- For timing chain and
VANOS repair information, see 117
Camshaft Timing Chain.
If it is
determined that the cylinder head will require signif-
icant reconditioning work, a remanufactured cylinder head
may be a good alternative. Remanufactured cylinder
heads are available from an authorized
BMW dealer.
The information given in this repair group is organized ac-
cording to engine code. For engine application information,
see
I00 Engine-General.
For specific repair procedures, refer to the appropriate repair
group:
* 020 Maintenance
100 Engine-General
113 Cylinder Head Removal and Installation
117 Camshafi Timing Chain
= 170 Radiator and Coo!ing System
Special Tools
Special BMW tools are required for most cylinder head ser-
vice described in this repair group. Many of these tools are ex-
pensive and only available through an authorized
BMW
dealer. If the special tools are not available, have the cylinder
head removed and disassembled by an authorized BMW
dealer. Be sure to read each procedure thoroughly before
starting a job to determine which special tools and equipment
will be necessary.
Most of the repairs to a cylinder head require precision
rna-
chine work to specific tolerances. This type of work should be
performed by an authorized BMW repairfacility or an ASE
certified machinist.
71 Torque wrench with flex shaft
Page 181 of 1002

Downloaded from www.Manualslib.com manuals search engine
11 6-5
I Cylinder Head and valvetrain1
4 Timing chain tensioner bracket (V-8)
(Tool No. BMW
11 7 380)
CYLINDER HEAD
This section provides the specifications and special recondi-
tioning information necessary to repair the cylinder heads
covered by this manual.
The disassembled cylinder head should be inspected for
warpage and cracks. Check the valve guides and valve seats
for wear before machining a warped head. Always decarbon-
ize and clean the head before inspecting it.
Visually inspect the cylinder head for craclts.
If a cracked cyl-
inder head is suspected and no
craclts are detected through
the visual Inspection, have the head further tested for cracks
by an authorized BMW dealer or an ASE certified machinist.
A cracked cylinder head must be replaced.
NOJE-
When disassembling and inspecting the cylinder head, be
sure to
checlc the camshaft carrier bearing surfaces using a
straight edge for
warpage, and check the lifter bores for wear.
A high-quality straight edge can be used to
checlc for
warpage. A warpage of 0.05 mm (0.002 in.) is acceptable
without machining. A warped cylinder head can be machined
provided no more than 0.3
mm (0.012 in.) of material is re-
moved.
If further machining is required, the head should be
replaced. Removing more than this amount will reduce the
size of the combustion chamber and adversely affect engine
performance. A 0.3 mm
thicker head gasket for machined
heads is available from an authorized BMW parts depart-
ment.
Page 184 of 1002
Downloaded from www.Manualslib.com manuals search engine
Cylinder Head and Valvetrain
&cylinder models: remove plastic top
- Pry out caps (arrows).
- Remove fasteners and covers. covers:
4 V-8 models: remove plastic top
covers:
Press down on locking pins
(arrows) to release locks and
remove top cover.
Pry out caps
(A) from covers.
Remove fasteners and covers.
4 Lift metal latch on coil harness connectors and disconnect
harness connectors from coils. 6-cylinder shown,
V-8 similar.
- Remove coil grounding straps.
NOTE-
Make note of ground wire at mounting studs arrangement
during removal.
- -- -
-
Page 185 of 1002
Downloaded from www.Manualslib.com manuals search engine
11 6-9
Cvlinder Head and valvetrain1
4 Remove ignition coils and spark plugs.
V-8 models: remove mounting nuts (arrows) from wiring har-
ness ducting.
< V-8 models: disconnect fuel injector electrical connectors
from injectors:
Pry one corner of wire
loclc clip (arrow) on first injector.
Repeat for all injectors.
Lift wire ducts off and set aside.
- V-8 models: disconnect battery jump start post terminal from
left cylinder head cover.
- 6-cylinder models: remove oil filler cap and unclip vent con-
nection from cylinder head cover.
- Remove cylinder head cover mounting fasteners and re-
move cylinder head cover(~).
NOTE-
The cylinder head cover mounting bolt insulators and gas-
Icets should be reinstalled in their original locations. Make
note of their arrangement
during removal.
Page 186 of 1002

Downloaded from www.Manualslib.com manuals search engine
Cylinder Head and Valvetrain
< Remove oil baffle cover from above intake camshaft(s)
- Rotate engine at crankshaft vibration damper center bolt in
normal direction of rotation (clockwise) until camshaft lobe of
lifter to be tested points away from the lifter, allowing valve to
be completely closed.
Use a plastic or wooden stick to press down on top of lifter
with approximately 3.5 Nm
(2.25 ft-ib) of force.
If the lifter collapses slightly as though spring loaded, air
may be trapped in the lifter.
NOTE-
Air trapped in hydraulic lifters may result from oil foaming (air
being drawn
in by the oil pump). This may be caused by a
faulty oil pump control valve O-ring; leaking oil pump pickup
gaslcet; or by oil starvation to pump.
Press down on top of lifter for
10 to 15 seconds uslng approx-
lmately 6 to 9 Nm (4.5 to 6.75 ft-lb) of force.
If anv clearance is created between the lifter and the
cam-
shafi lobe, the check valve in the lifter is not closing. Re-
place lifter.
- To replace a hydraulic lifter, remove appropriate camshaft.
Refer to camshaft removal procedures given in Camshaft
and lifter removal and installation.
Once camshaft is removed, withdraw faulty
lifter(s) and re-
place with new
lifter(s). Inspect lifter bores for wear and scor-
ing at arrows.
- Reinstall camshafts. See Camshaft and lifter removal and
installation.
Page 187 of 1002

Downloaded from www.Manualslib.com manuals search engine
Cylinder Head and Valvetrain
4 Install intake camshaft oil baffle cover and cylinder head cov-
er:
= Checlc for correct seating of half-moon seals (A) in back of
cylinder head cover.
Use a small amount of Three Bond 1209
@or equivalent
sealant at corners
(B) of half-moon cutouts and corners in
front of cylinder head at joint to timing chain cover.
Align cover at front and rear, then alternatively tighten fas-
teners from inside to outside.
Tightening torque
Sparic plug to cylinder head 25 Nm (18 it-lb)
Ignition coils to cylinder head 10 Nrn (7.5 ft-lb)
Cylinder head cover to cylinder iiead 10 Nrn (89 in-lb)
fM6 screws)
CAMSHAFT AND LIFTER REMOVAL
AND ~NSTALLATION
The camshafts can be removed with the cylinder heads
mounted on the engine (in the car).
On 6-cylinder engines there are two different procedures giv-
en, depending on whether the engine is equipped with single
VANOS (M52 engine) or double VANOS
(M52TU or M54 en-
gine).
For V-8 engines, camshaft removal and installation proce-
dures are
only included for the non-VANOS (M62) engine.
Camshaft removal and installation for the
VANOS eq;ipped
V-8 (M62TU) is not covered in this manual.
Special BMW service tools should always be used to remove
and install the camshafts. Removal of the camshafts without
the special tools can result in cylinder head damage and cam-
shaft breakage.