Front BMW 525i 2001 E39 Repair Manual

Downloaded from www.Manualslib.com manuals search engine
117-18
Camshaft Timing Chain
4 Loosen 4 bolts (arrows) from exhaust camshait sprocket
(Torx E10).
Press down on secondary chain tensioner and lock into place
using BMW special tool
11 3 292 or a similar size pin.
NOTE-
Two types of secondary timing chain tensioners are used;
one with two holes, and one with a single hole for the
locl pin tool.
Remove VANOS control unit mounting fasteners at front of
cylinder head.
4 Install sprocltet rotating tool (BMW special tool 11 5 490) on
exhaust camshaft.
- Rotate exhaust camshaft sprocket clockwise while sliding
VANOS control unit forward to remove from cylinder head.

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.

Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing Chain Timing chains, removing
(M52 engine)
Camshaft timing chain removal on M52 engines requires en-
gine oil pan removal.
Special
BMW sewice tools are needed for timing chain re-
moval and installation procedures. The special tools assure
propertiming of thevalvetrain. Precise marks to
setthe timing
on the camshafts are not provided for reassembly. Read the
procedures through before beginning the job.
NOTE-
If the camshafts are not properly timed, the pistons can con-
tact the valves.
- Remove VANOS control unit. See VANOS control unit, re-
moving (M52 engine).
- Remove radiator cooling fan and shroud. See 170 Radiator
and Cooling System.
- Drain cooling system. See 170 Radiator and Cooling Sys-
tem.
- Remove coolant hoses from thermostat housing and remove
thermostat housing from front of cylinder head.
- Loosen bolts for coolant pump pulley.
- Remove drive belts for alternator and AIC compressor. See
020 Maintenance.
- Remove coolant pump pulley.
Remove drive belt tensioner mounting bolts (arrows) and re-
move tensioner from front of engine.
- Remove engine speed sensor from lower timing chain cover.

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

Downloaded from www.Manualslib.com manuals search engine
-- -
Chain 1
- Install cylinder identification trigger plate to front of intake
camshaft.
- Install spacer to front of intake camshaft
- Install secondary chain sprockets and chain as an assembly
so that arrows on sprockets are pointing up. Center mounting
holes in sprockets to bolt holes in camshafts.
4 lnstall thrust washers and spring plate to intake cam
sprocket.
Tighten intake camshaft sprocket nuts.
- Install VANOS control unit, see VANOS control unit, install-
ing
(M52 engine).
Tightening torque
Intake camshaft sprocket nuts to studs
(ME) 1011 Nm (8919 In-lb) 502117068
- Unlock and release secondary chain tensioner,
4 Preload primary timing chain by torquing adjustable primary
chain tensioner (BMW special tool
11 4 220) to 1.3 Nm
(11 in-lb).
- Tighten exhaust camshaft sprocket bolts in two stage
Tightening torque Exhaust camshaft sprocket bolls (M7)
Stage 1
5 Nrn (44 in-lb)
Stage
2 22 Nm (17 ft-lb)
- Remove crankshaft locking tool and camshaft locking tools.
< Align hub with keyway and tap into place. Insert new center
bolt with washer shoulder (arrow) facing hub.
CAUTION-
Inspect woodruff ley for damage before installing hub.
- Attach crankshaft holding tool (BMW special tools 11 2
15011 1 2 410) to hub. Counterhold hub with tool while tight-
ening center bolt.
CAUTION-
Do not use flywheel locling tool to hold crankshaft stationary
to loosen or tighten
cranlshaft hub center bolt. Use only the
special tools specified, or equivalent hub holding tool.

Downloaded from www.Manualslib.com manuals search engine
Camshaft Timing Chain
- Connect electrical harness connectors to camshaft position
sensors and VANOS solenoid valves.
- Remove BMW special locking tools from rear of cylinder
head.
- Remove cranltshaft locking tool and replace sealing plug.
Install intake camshaft baffle and cylinder head cover.
Checlc for correct seating of half-moon seals (A) in back of
cylinder head cover.
Use a small amount of Three Bond 1209
O or equivalent
sealant at corners
(B) of half-moon cutouts.
Similarly, seat gasket and
seal corners in front of cylinder
head, at VANOS control unit.
Tightening torque
Cylinder head cover to cylinder head
(M6) 10 Nm (89 in-lb)
- Remainder of installation is reverse of removal.
Tightening torques
Radiator fan (viscous clutch) to
coolant pump 40
Nm (30 ft-lb)
Spark plug to cylinder head
25 Nrn (18 ft-lb)
VANOS timing, checking and adjusting
(M52 TU and M54 engines)
Use this procedure to check and, if necessary, adjust cam-
shaft timing. This procedure assumes that the cylinder head
cover and intake
camshaft plastic baffle have been removed.
Also, be sure the cooling fan and the spark plugs have been
removed.
Remove primary camshaft chain tensioner cylinder
(arrow).
~~ ~ ~~ ~--~
CA UTlOAC
Primary camshaft chain tensioning piston is under spring
pressure.

Downloaded from www.Manualslib.com manuals search engine
-
I Camshaft Timing Chain - --
Install BMW special tool 11 6 150 (VANOS setup bracket) to
front of cylinder head timing case. Tighten nuts
(arrows) by
hand, and then tighten down uniformly until special tool is in
full contact with cylinder head.
CAUTION-
Male sure all gasket material is removed from face of cylin-
der head. Clean
sealins face and keep free of oil.
Secure camshaft impulse sprockets and wheels:
Pretighten Torx screws
(A) on exhaust camshaft impulse
wheel to approx.
5 Nm (44 in-lb).
Pretighten mounting nuts
(B) on exhaust and intake
sprocket assemblies to approx.
5 Nm (44 in-lb).
- Torque down Torx screws (A) and nuts (8) to flnal
specifications.
Tightening torques Sprocket assembly
to camshaft
initial torque
5 Nm (44 in-lb)
Sprocket assembly to camshaft
M7 Torx screw (A) 20 Nm (15 fl-lb)
ivl6 mounting nut (B) 10 tdm (89 in-lb)
- Remove flywheel locking tool from transmission bellhousing
so that crankshaft is no longer locked.
- Remove camshaft locking tools from rear of cylinder head.
- Crank engine over twice by hand in direction of rotation until
cylinder
1 intake and exhaust camshaft lobes face each other - again.
- Secure crankshaft with BMW special tool 11 2 300.
4 Place BMW special tool 11 3 240 over camshaft ends and
measure clearance of tool to cylinder head surface.
NOJE-
If the exhaust side of the tool (A) is not flush with the head,
camshaft timing
Is incorrect. Repeat camshaft timing pro-
cedure.
* Due to flexible sprocket design and VANOS control unit tol-
erances and play, the
intake side of special tool 11 3 240
(6) may be up to 1 mm (0.04 in) above the sudace of the
cylinder head. This is normal. Otherwise, repeat camshaft
timing procedure.

Downloaded from www.Manualslib.com manuals search engine
-- - -- - -- Camshaft Timing chain1
- Remove camshaft locking tools from rear of camshafts
- Remove BMW special tool 11 4 220 (adjustable primary
chain tensioner). Reinstall primary chain tensioner.
Tightening torque Primary chain tensioner to cylinder head
70
Nm (52 it-lb)
- Remove crankshaft locking tool from transmission bellhous-
ing. Reinstall sealing plug.
- Remove VANOS setup bracket from front of cylinder head
- lnstall VANOS control unit as described earlier in this group.
- Remove compressed air fitting (BMW special tool 11 3 450)
from VANOS control unit.
- Fit VANOS oil line banjo bolt with new seals. Attach oil line to
VANOS control unit.
Tightening torque
Oil line to VANOS control unit (banjo bolt) 32 Nm (24 H-lb)
- Remainder of installation is reverse of removal, noting the fol-
lowing:
lnstall spark plugs.
* lnstall intake camshaft plastic baffle prior to installing cylin-
der head cover. lnstall ignition coil packs and connect elec-
trical harness connectors.
Install radiator cooling fan.
- lnstall air filter housing and top engine cover.
Tightening torque Radiator cooling fan
(VISCOUS clutch) to 40 Nm (30 ft-lb)
coolant pump
Cyitnder head cover to cylinder head 10 Nm (89 in-lb)
Sparlc plug to cylinder head 25 Nm (18 ft-lb)

Downloaded from www.Manualslib.com manuals search engine
-
Camshaft Timing chain1
< Remove intake camshaft sprocket mounting nuts (arrows)
and remove spring plate (labelled
FRONT).
Remove tom screws from exhaust camshaft sprocket
(arrows).
Lift off exhaust and intake sprockets with secondary chain,
thrust spacer
(A) and splined shaft (B).
CAUTION-
Splined shafts for both intake and exhaust camshafts share
the same part
numbe,: Remove and mark used splined
shafts in order to reinstall in original locations.
4 Remove exhaust camshaft splined sleeve (A) and shaft (8).

Downloaded from www.Manualslib.com manuals search engine
1 17-62
Camshaft Timing Chain
4 Install intake camshaft spring plate so that FRONT mark is
visible. Install mounting nuts (arrows) finger tight.
4 Worlting at exhaust side, insert sprocket mounting Torx
screws into threaded lioles (arrows).
Initially tighten screws to approx.
5 Nm (44 in-lb), then back
off one-half turn.
4 Fit thrust spacer (A) on exhaust camshaft.