Vanos Control Unit, Removing (M52 Engine) - BMW 5251 Service Manual

I
Camshaft Timing Chain
Mark 0" location on socket (arrow). Tighten hub bolt in four
stages.
Tightening torque
Vibration damper
hub
to cranlrshaft
Stage
1 100 Nm (74
it-lb)
Stage
2 60"
Torque angle
Stage
3 60"
Torque angle
Stage 4
30"
Torque angle
-
install vibration damper and mounting bolts
NOTE-
Male sure to align vibration damper with locating dowel pin
in hub.
Tightening torque
Vibration damper to cranltshait hub (ME)
22 Nm (16
ft-lb)
-
Install drive belts. See 020 Maintenance.
-
Install cooling fan. See 170 Radiator and Cooling System.
-
Replace under engine splash shield, then reconnect nega-
tive battery cable.
!/ANBS CONTROL
UNIT AND
TIMING CHAIN (M52
ENGINE)
VANOS control unit, removing (M52 engine)
NOTE-
Special BMW service tools are required to remove and in-
stall the VANOS control unit. Read the procedure through
before starting the job.
If the camshafts are notproperly timed, the pistons can
contact the valves.
-
Disconnect negative (-) cable from battery.
CAUTION-
Disconnecting the battery may erase fault code(s) stored in
control module memory. Prior to disconnecting the battev,
check for fault codes using special BMW diagnostic equip-
ment.
*
Prior to disconnecting the battery, read the battery dis-
connection cautions given in 001 General Cautions
and Warnings.