Page 230 of 1002

Downloaded from www.Manualslib.com manuals search engine
11 6-54
Cylinder Head and Valvetrain
Replace primary timing chain tensioner O-ring (arrow) in
right cylinder head.
- lnstall right upper timing cover to engine:
Remove old gasket from right timing cover.
Clean gasket groove and install new gasket.
Apply Three Bond
12098sealant to joint between cylinder
head and timing cover. Install remaining timing cover bolts
finger tight.
lnstall left upper timing chain cover to engine:
Remove old gasket from right timing chain cover.
Clean gasket groove and install new gasket.
Insert lower cover timing chain cover retaining bolt (arrow)
to cover, then fit cover to cylinder head.
Apply Three Bond 12098 sealant to joint between cylinder
head and timing chain cover. lnstall upper timing cover
bolts finger tight.
4 Remove cylinder head cover sealing gaskets from right cyl-
inder head cover. lnstall BMW special tool 11
1 41 1 into gas-
ket groove of cylinder head cover.
lnstall right cylinder head cover with BMW special tool
11
1 41 1 to right cylinder head. Fit cylinder head cover retain-
ing nuts to cylinder head cover studs at cylinders
1 and 2
(first two cylinders on right cylinder head).
Tighten nuts uniformly in
'I2 turn steps.
NOTE-
BMW special tool 11 1 41 1 presses upper timing chain cover
to level of cylinder head.
Tightening torque Cylinder head cover nuts
10 Nm (7.5 n-lb)
- Tighten right upper timing cover retaining bolts in two passes.
Tightening torque
Timing chain cover to head
10 Nm (7.5 ft-lb)
Page 231 of 1002

Downloaded from www.Manualslib.com manuals search engine
11 6-55
Cvlinder Head and valvetrain1
4 Remove cylinder head cover sealing gasltets from left cylin-
der head cover. Install BMW special tool 11 1 412 into gasket
groove of cylinder head cover.
Install left cylinder head cover. Fit cylinder head cover re-
taining nuts to cylinder head cover studs at cylinders
5 and
6 (first two cylinders on left side cylinder bank).
* Tighten nuts uniformly in 'I? turn steps.
NOTE-
BMW special tool 11 1 4 12presses upper timing chain cover
to level of cylinder head.
Tightening torque Cylinder head cover
nuts 10 Nm (7.5 it-lb)
- Tighten left upper timing chain cover retaining bolts in two
passes.
Tightening torque
Timing chain cover to head
10 Nm (7.5 ft-lb)
- Remove cylinder head covers and remove BMW special
tools 11 4 41 11412 from cylinder head covers.
- Fit new gasket to cylinder head cover without strain.
- Apply Three Bond@ 1209 sealant to joints between cylinder
head and timing cover.
4 Malte sure half-moon cutouts (A) at rear of cylinder heads fit
correctly to cylinder head sealing surface. Apply Three
Bond@ 1209 sealant at corners of half-moon cutouts (B).
- Remainder of installation is reverse of removal.
Page 251 of 1002

Downloaded from www.Manualslib.com manuals search engine
Camshaft Timina chain1
- Remove viscous clutch cooling fan. See 170 Radiator and
Cooling
System.
CA UTlOEIC
The radiator cooling fan nut (32mm wrench) has left- hand
threads.
.
< Remove engine trim covers:
Pry out plastic trim caps (arrows).
. Remove cover fasteners and covers.
4 Remove ignition coils:
0 Disconnect ignition coil electrical harness connectors
Remove
coil mounting fasteners and remove coils.
Remove spark plugs.
NOTE-
Make note of ignition coil ground strap locations.
Disconnect VANOS electrical harness connector
(A) and oil
line fitting
(B) from VANOS control unit.
NOTE-
Wrap the VANOS oil line fitting with a shop rag to absorb
leaking oil.
- Disconnect cranltcase breather by squeezing at arrows,
- Remove cylinder cover mounting fasteners and remove
cylinder head cover.
NOTE-
The cylinder head cover mounting bolt insulators and gas.
kets should be reinstalled in their original positions. Make
note of their arrangement during removal.
Page 255 of 1002
Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing chain1
VANOS control unit, installing (M52 engine)
CAUTION-
Incorrect installation of the VANOS control unit may result in
damage to the engine.
- Make sure camshafts and crankshaft are loclted in TDC po-
sition with BMW special tools as described during VANOS
removal.
< Rotate exhaust camshaft sprocket clocltwise (as viewed from
front of engine) using BMW special tool
11 5 490, until detent
position stop is reached.
4 Apply a small amount of liquid gasket sealer (Three Bond
1209
8 or equivalent) to VANOS housing alignment dowels
on front of cylinder head. Install a new
gasket.
< Push VANOS piston gear cup (arrow) into VANOS housing
until it bottoms out. Position VANOS control unit in front of
camshafts, but do not engage splines on gear cup.
Page 259 of 1002
Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing Chain
4 Disconnect VANOS electrical harness connector (A) and oil
line fitting
(B) from VANOS control unit.
NOTE-
Wrap the VANOS oil line fitting with a shop rag to absorb
leaking oil.
Disconnect cranltcase breather by squeezing at arrows.
- Remove cylinder cover mounting fasteners and remove
cylinder head cover.
NOTE-
The cylinder head cover mounting bolt insulators andgas-
lets should be reinstalled in their original positions. Make
note of their arrangement during removal.
4 Remove oil baffle cover from intake camshaft
Page 263 of 1002

Downloaded from www.Manualslib.com manuals search engine
4 With crankshaft at TDC position, remove vibration damper
bolts (arrows) and remove vibration damper.
< Mount crankshaft holding tool (BMW special tool 11 2 150
and
11 2 410) to crankshaft hub. Counter hold crankshaft and
loosen crankshaft hub retaining bolt.
Crankshaft hub retaining bolt is torqued to
410 Nm (300 ft-lb).
Do not use flywheel
locliing tool to hold cranl(shait stationary
to loosen or tighten crankshaft hub center bolt. Use only the
special tools specified, or equivalent hub holding tool.
- Remove crankshaft hub.
- Remove cylinder cover mounting fasteners and remove cyl-
inder head cover.
NOTE-
The cylinder head cover mounting bolt insulators and gas-
lets should be reinstalled in their original positions. Make
note of their arrangement during removal.
- Drain engine oil, remove oil pan. See 119 Lubrication Sys-
tem.
Remove primary timing chain tensioner (arrow).
CAUTION-
Timing chain tensioner is under spring tension. I
- Remove VANOS control unit. See VANOS control unit, re-
moving
(M52 engine).
- Remove fasteners from intake and exhaust camshaft
sprocket.
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 267 of 1002

Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing chain1
Tap locating dowels into cover until they protrude 2 to 3 mm
from sealing surface.
- Using new gaskets, install lower timing chain cover:
Tap cover into position to engage dowels.
Install timing chain cover fasteners and tighten to
5 Nm (44
in-lb).
Drive dowels in flush to front of cover.
. Tighten cover mounting bolts alternately and in stages.
Install cylinder head to timing chain cover fasteners and
tighten.
Tightening torques Lower timing chain cover to block
M7 15 Nm (1 1 ft-lb)
ME 20 Nm (15 it-lb)
- Replace front crankshaft radial seal. See Crankshaft oil
seal, front, replacing
(M52 engine).
Install engine oil pan using
a new gasket. See 119 Lubrica-
tion System.
Mount primary timing chain sprocket to primary
cha~n so that
arrow on sprocket faces up. Mount sprocket to camshafl so
that tapped holes in camshaft are on left side of elongated
holes in sprocket.
4 Install adjustable timing chain tensioner (BMW special tool
11 4 220). Thread tool in finger tight until slack is removed
from chain.
NOTE-
BMW special tool 11 4 220 is an adjustable timing chain ten-
sioner that simulates the function of the hydraulic tensioner.
- Check that elongated holes in primary sprocket are centered
to bolt holes in camshafl and chain is free of slack.
- Install secondary timing chain guide and secondary chain
tensioner. Tighten mounting bolts (tensioner remains
locited
down).
F81.,,l,ryT-iib.l>nii,:oni-Aii Ri"ilti R