1999 BMW 525i Workshop Manual

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Cylinder Head and Valvetrain
< Disconnect fuel injector electrical connectors from injectors.
Pry corner of wire lock clip (arrow) on first injector.
* Repeat for all injectors.
Lift wiring ducts off and set aside.
4 Remove right and left side ignition coil mounting nuts (ar-
rows) and coils.
NOTE-
Male note of location for ground straps (arrow A).
- Remove spark plugs.
- Disconnect positive (+)jumper junction from top of lefl cylin-
der head cover.
4 Remove retaining nuts (arrows) and remove oil lines from
left and right cylinder heads.

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11 6-42
/ Cvlinder Head and Valvetrain
4 Using crankshaft center bolt, rotate engine clockwise one
complete rotation until the first cylinder is at TDC.
4 Confirm TDC position. Lobes of camshafts for cylinder head
1-4 (passengers side) should point up (arrows).
4 Remove timing chain tensioner (arrow) from right side upper
timing chain cover.
- Remove secondary air injection pipes in front of upper timing
chain covers.
- Remove left and right coolant hoses from coolant pump
housing.
- Detach dipsticlc tube from upper right timing cover,

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Cylinder Head and valvetrain1
4 Remove camshaft position sensor (A) from timing chain cov-
er. Remove bolts
(arrows) from timing chain covers and re-
move covers from right and left cylinder heads.
4 Counterhold intalte carnshaft on right cylinder head
4 Counterhold right intalte camshaft and remove sprocltet
mounting bolts
(arrows) from right cylinder head.
Remove carnshaft impulse wheel and primary chain
sprocket.
- Slide primary timing chain off sprocltet and suspend chain
with stiff wire to prevent it from dropping into lower timing
chain cover.

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..
ICylinder Head and Valvetrain -.I
4 Counterhold left intake camshaft and remove sprocket
mounting bolts
(arrows) from left cylinder head.
Remove primary chain sprocket.
Slide primary timing chain off sprocket and
supend timing
chain with stiff wire to prevent it from dropping into lower
timing chain cover.
4 Using cranltshaft center bolt, rotate engine counterclockwise
to
45" before TDC position. 45" V.OT mark on pulley will
align with boss cast on engine block
(arrow).
4 Compress secondary chain tensioners and lock (arrows)
using BMW special tool 11 3 310 or a stiff wire.

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Cylinder Head and valvetrain1
While counter holding camshaft, remove exhaust camshaft
sprocket bolts
(arrows) from left cylinder head. Remove
sprocltets with chain.
< While counter holding camshaft, remove exhaust camshaft
sprocket bolts
(arrows) from right cylinder head. Remove
sprocltets with chain.
4 Use BMW special tool 11 3 430 to rotate camshaft into disas-
sembly position.
4 Loosen camshaft bearing caps nuts in correct sequence
(1-10) (left cylinder head shown).
NOTE -
Keep camshaft bearing caps in order. Used caps must not be
interchanged.
- Remove exhaust camshaft by repeating process.
0 Remove camshafts from cylinder head.
- Repeat camshaft removal process for right cylinder head.

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11 6-46
/cylinder Head and Valvetrain
I I Camshafts, installing, right cylinder head (M62 engine)
I
1
A: / Camshafts are marked at rear. Install camshafts into cam-
shaft bearing saddles of cylinder heads.
Intake camshaft for right cylinder head
(14) is labelled
E 1-4.
Exhaust camshaft for right cylinder head (1-4) is labelled
A 1-4.
4 Rotate camshafts so that recesses in Intake and exhaust
camshafts
polnt upward 30 to 40' above seal~ng surface for
valve cover (arrows).
4 Bearing caps are marked with a code for location.
NOTE-
The camshaft caps are stamped with a code letter - "E" for
the intake side and
'N" for the exhaust side. Number code is
forposition on head, with number
7 being the front bearing
cap.
CAUTION--
Do not mix up camshafi bearing caps between cylinder
banks.

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1 Cvlinder Head and valvetrain1
Evenly tighten down bearing cap nuts in 'I? turn steps start-
ing at number
1.
Tightening torque
Camshaft bearing cap 14 Nm (10 ft-lb)
BMW special tool 11 3 430 on camshaft.
4 Rotate camshafts until marker bores (arrows) point up-
wards.

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1 16-48
/Cylinder Head and Valvetrain
Cylinders
1-4
11 2 445 11 2441
4 Secure camshafts in TDC position using BMW special tools:
Align camshafts with open-end
27 mm wrench so BMW
special tools fit on cylinder heads without gaps. Secure
tool using number 4 cylinder spark plug hole.
Do not damage the cylinder head. If
necessa& machine
open-end wrench to fit.
Left side (cyl.
5-8) camshafts, installing (M62 engine)
4 Camshafts are marked for location at rear. Install camshafts
into camshaft bearing saddles of cylinder heads, noting the
following:
Intake camshaft for left cylinder head
(5-8) is labelled
E 518.
Exhaust camshaft for left cylinder head (5-8) is labelled
A
518.
4 Rotate camshafts so that recesses in intake and exhaust
camshafts point downward 30 to 40" (arrows) from cylinder
head cover sealing surface.