11 36 090 Removing and installing/replacing toothed shafts of VANOS gear on left and right (S62)

WARNING: This page is about a different car, the 2003 BMW Z8, 2002 BMW Z8, 2001 BMW Z8, and 2000 BMW Z8. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

11 2 300
11 7 120
11 7 130
11 7 150
11 7 200
12 6 050
12 6 410
12 6 411

Read fault memory and make a documentary record.

Open drain plug on radiator. Unfasten drain plug for coolant on right engine block. Drain and dispose of coolant.

Installation:

Replace drain plug sealing ring on engine block.

Tightening torque, 25 Nm.

Top up coolant. Vent cooling system and check for leaks. Refer to 17 00 005 DRAINING AND ADDING COOLANT (S62) .

Remove intake filter housing upper section with air-mass flow sensor.

Remove intake air manifold. Refer to 11 61 050 Removing and installing intake air manifold (S62) .

Remove both cylinder head covers. Refer to 11 12 004 REMOVING AND INSTALLING/SEALING BOTH CYLINDER HEAD COVERS (S62) .

Remove all spark plugs.

Remove water hoses between radiator and thermostat housing.

Remove fan clutch with fan impeller and fan cowl. Refer to 11 52 020 Removing and installing or replacing fan clutch (S62) and 17 11 031 REPLACING FAN COWL (S62) .

Remove oil lines (1) from cylinder head on cylinder banks 1 to 4 and 5 to 8.

NOTE: The oil lines (1) of cylinder banks 1 to 4 and 5 to 8 are different.

Fig 1: Removing Oil Lines

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NOTE: Joint removal and installation of the VANOS adjustment unit on cylinder banks 1 to 4 and 5 to 8 requires a step-by-step procedure.

The work steps alternate between cylinder banks 1 to 4 and 5 to 8.

Removal:

Removal of the VANOS adjustment unit and the toothed shafts is described separately from installation. The assembly sequence for removal and installation is different.

When the engine is switched off, VANOS moves the camshafts to a position which is advantageous to engine starting.

CAUTION: Before the VANOS adjustment unit is removed, the camshafts on both cylinder banks must be rotated back to their initial position.

Rotate crankshaft in direction of rotation as far as ignition TDC position of cylinder 1. Secure vibration damper in position with special tool 11 2 300.

Fig 2: Securing Vibration Damper

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Cylinder bank 1 to 4:

Remove oil line from VANOS adjustment unit.

Fig 3: Removing Oil Line From VANOS Adjustment Unit

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Cylinder bank 1 to 4:

Fit special tool 11 7 130 to VANOS adjustment unit.

Fig 4: Fitting Special Tool

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Connect compressed air (2 to 8 bar).

Cylinder bank 1 to 4:

Disconnect plug connection for solenoid valves on cylinder bank 1 to 4.

Connect special tool 12 6 050 in conjunction with special tool 12 6 411 (from special tool kit 12 6 410) to solenoid valves on cylinder bank 1 to 4. Connect special tool 12 6 411 to correct terminals on car battery.

Fig 5: Connecting Special Tool

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Alternately press toggle switch buttons 1 and 2 several times on special tool 12 6 050.

CAUTION: Do not damage the cylinder head.
If necessary, machine open-end wrench accordingly.

Fig 6: Fitting Open-End Wrench

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Cylinder bank 1 to 4:

Press and hold down toggle switch button 1 on special tool 12 6 050.

Simultaneously rotate inlet camshaft at hexagon against direction of rotation up to stop.

Fig 7: Rotating Inlet Camshaft

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NOTE: The splines in the VANOS gear are now in contact; the inlet camshaft cannot be rotated further.

Cylinder bank 1 to 4:

Alternately press toggle switch buttons 3 and 4 several times on special tool 12 6 050.

Fig 8: Pressing Toggle Switch Buttons

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Cylinder bank 1 to 4:

Press and hold down toggle switch button 3 on special tool 12 6 050.

Simultaneously rotate exhaust camshaft at hexagon against direction of rotation up to stop.

NOTE: The splines in the VANOS gear are now in contact; the exhaust camshaft cannot be rotated further.

Fig 9: Rotating Exhaust Camshaft

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Cylinder bank 5 to 8:

Remove oil line from VANOS adjustment unit.

Fig 10: Removing Oil Line From VANOS Adjustment Unit

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Cylinder bank 5 to 8:

Fit special tool 11 7 130 to VANOS adjustment unit.

Fig 11: Fitting Special Tool

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Connect compressed air (2 to 8 bar).

Cylinder bank 5 to 8:

Disconnect plug connection for solenoid valves on cylinder bank 5 to 8.

Connect special tool 12 6 050 in conjunction with special tool 12 6 411 (from special tool kit 12 6 410) to solenoid valves on cylinder bank 5 to 8. Connect special tool 12 6 411 to correct terminals on car battery.

Fig 12: Connecting Special Tool

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Alternately press toggle switch buttons 4 and 3 several times on special tool 12 6 050.

Cylinder bank 5 to 8:

Press and hold down toggle switch button 4 on special tool 12 6 050.

Simultaneously rotate inlet camshaft at hexagon against direction of rotation up to stop.

Fig 13: Rotating Inlet Camshaft

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NOTE: The splines in the VANOS gear are now in contact; the inlet camshaft cannot be rotated further.

Cylinder bank 5 to 8:

Alternately press toggle switch buttons 2 and 1 several times on special tool 12 6 050.

Fig 14: Pressing Toggle Switch Buttons

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Cylinder bank 5 to 8:

Press and hold down toggle switch button 2 on special tool 12 6 050.

Simultaneously rotate exhaust camshaft at hexagon against direction of rotation up to stop.

Fig 15: Rotating Exhaust Camshaft

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NOTE: The splines in the VANOS gear are now in contact; the exhaust camshaft cannot be rotated further.

Remove special tool 11 2 300. Rotate crankshaft in direction of rotation a further revolution up to overlap TDC position.

Cylinder bank 1 to 4:

Slacken six accessible bolts two turns.

Fig 16: Slackening Accessible Bolts

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Cylinder bank 5 to 8:

Slacken six accessible bolts two turns.

Fig 17: Slackening Accessible Bolts

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Crank engine at central bolt in direction of rotation until 1st cylinder is at TDC firing position.

Secure vibration damper in position with special tool 11 2 300.

Fig 18: Securing Vibration Damper

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Cylinder bank 1 to 4:

Slacken six accessible bolts two turns.

Fig 19: Slackening Accessible Bolts

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Cylinder bank 5 to 8:

Slacken remaining six bolts two turns.

Fig 20: Slackening Remaining Bolts

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Cylinder bank 1 to 4:

NOTE: The camshafts have an opening. The 1st bearing caps have a locating bore.

Align camshaft opening to locating bore in bearing cap and secure in position with special tool 11 7 120.

Fig 21: Securing Camshaft

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Cylinder bank 5 to 8:

Align camshaft opening to locating bore in bearing cap and secure in position with special tool 11 7 120.

Fig 22: Securing Camshaft

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Cylinder bank 1 to 4:

Release screws on VANOS adjustment unit.

Fig 23: Releasing Screws On Vanos Adjustment Unit

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Cylinder bank 1 to 4:

Carefully lever out VANOS adjustment unit at "intended" openings with a screwdriver on left and right.

Fig 24: Levering Out VANOS Adjustment Unit

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Cylinder bank 1 to 4:

Detach VANOS adjustment unit together with toothed shafts.

Fig 25: Detaching VANOS Adjustment Unit

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Cylinder bank 5 to 8:

Release screws on VANOS adjustment unit.

Fig 26: Releasing Screws On Vanos Adjustment Unit

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Cylinder bank 5 to 8:

Carefully lever out VANOS adjustment unit at "intended" openings with a screwdriver on left and right.

Fig 27: Levering Out Vanos Adjustment Unit

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Cylinder bank 5 to 8:

Detach VANOS adjustment unit together with toothed shafts.

Fig 28: Detaching VANOS Adjustment Unit

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Cylinder bank 1 to 4:

Connect special tool 12 6 050 in conjunction with special tool 12 6 411 to solenoid valves of VANOS adjustment unit.

Fig 29: Connecting special tool

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Connect special tool 12 6 411 to correct terminals on car battery.

Press button 4 on special tool 12 6 050 and simultaneously pull out toothed shaft of exhaust side by hand up to stop.

Press button 2 on special tool 12 6 050 and simultaneously pull out toothed shaft of inlet side by hand up to stop.

Cylinder bank 1 to 4:

CAUTION: CCW thread!

Brace against twin surface (1) and release hex head (2).

Release toothed shaft screw connection on inlet and exhaust sides.

Fig 30: Releasing Toothed Shaft Screw Connection

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Cylinder bank 5 to 8:

Connect special tool 12 6 050 in conjunction with special tool 12 6 411 to solenoid valves of VANOS adjustment unit.

Fig 31: Connecting special tool

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Connect special tool 12 6 411 to correct terminals on car battery.

Press button 1 on special tool 12 6 050 and simultaneously pull out toothed shaft of exhaust side by hand up to stop.

Press button 3 on special tool 12 6 050 and simultaneously pull out toothed shaft of inlet side by hand up to stop.

Cylinder bank 5 to 8:

CAUTION: CCW thread!

Brace against twin surface (1) and release hex head (2).

Release toothed shaft screw connection on inlet and exhaust sides.

Fig 32: Releasing Toothed Shaft Screw Connection

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Installation:

Installation of the toothed shafts and the VANOS adjustment unit is described separately from removal. The assembly sequence for installation and removal is different.

CAUTION: Risk of mixing up parts.

The VANOS adjustment units of cylinder banks 1 to 4 and 5 to 8 are different.

Cylinder bank 1 to 4
Cylinder bank 5 to 8

Fig 33: Identifying VANOS Adjustment Units

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NOTE: Install VANOS adjustment unit so that cables of solenoid valves are at bottom.

Cylinder bank 1 to 4:

CAUTION: CCW thread!

Install toothed shafts of inlet and exhaust sides.

Fig 34: Installing Toothed shafts

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Brace against twin surface (1) and release hex head (2).

Tightening torque 10 Nm.

NOTE: Coat all sliding surfaces on toothed shafts with engine oil as lubricant.

Cylinder bank 1 to 4:

Oil is sprayed when splined shafts are pressed back. Cover bore (1) with a cloth.

Connect special tool 12 6 050 in conjunction with special tool 12 6 411 to solenoid valves of VANOS adjustment unit.

Fig 35: Connecting Special Tool

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Connect special tool 12 6 411 to correct terminals on car battery.

Press button 1 on special tool 12 6 050 and simultaneously press back toothed shaft of inlet side by hand up to stop.

Press button 3 on special tool 12 6 050 and simultaneously press back toothed shaft of exhaust side by hand up to stop.

Cylinder bank 1 to 4:

Replace O-rings (1 and 2) on VANOS adjustment unit.

Coat O-rings (1) with oil as anti-friction agent.

CAUTION: O-rings (2) fall out very easily, secure with grease if necessary.

Fig 36: Replacing O-Rings

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Cylinder bank 1 to 4:

Rotate spline hubs (1) of inlet and exhaust camshafts to right stop.

Fig 37: Rotating Spline Hubs

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Cylinder bank 1 to 4:

Attach VANOS adjustment unit.

Fig 38: Attaching VANOS Adjustment Unit

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Cylinder bank 1 to 4:

CAUTION: Ensure that both VANOS splined shafts remain in initial position during assembly procedure.

Rotate splined shafts of inlet and exhaust sides until straight splines are engaged.

Push VANOS adjustment unit with splined shaft into VANOS gear until helical cut splines (2) are positioned shortly before meshing with spline hub (1).

Fig 39: Pushing In VANOS Adjustment Unit

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Cylinder bank 1 to 4 (exhaust side):

If the helical cut splines cannot be pushed into the spline hub (1):

Place special tool 11 7 150 on bore in spline hub (1). Rotate spline hub (1) against direction of rotation until splined shaft (2) is positioned with spline hub (1) exactly "tooth-to-tooth gap".

CAUTION: The "first" fitting tooth must snap into place.

Fig 40: Rotating Spline Hub

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Cylinder bank 1 to 4 (inlet side):

Place special tool 11 7 150 on bore in spline hub (1). Rotate spline hub (1) against direction of rotation until splined shaft (2) is positioned with spline hub (1) exactly "tooth-to-tooth gap".

CAUTION: The "first" fitting tooth must snap into place.

Fig 41: Rotating Spline Hub

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Cylinder bank 1 to 4 (inlet side):

Align radial piston pump to driver on spline hub.

NOTE: Picture shows a schematic representation.

Fig 42: Aligning Radial Piston Pump To Driver

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Cylinder bank 1 to 4:

Push on VANOS adjustment unit only until O-rings of VANOS adjustment unit rest against timing case cover.

CAUTION: If this position is not reached, realign position of radial piston pump to driver.

Insert one bolt each on left and right and initially tighten without play. The bolts serve to locate the VANOS adjustment unit in position. Do "not" tighten down bolts yet. VANOS adjustment unit must "not" rest against timing case cover.

Fig 43: Inserting Bolt On Left And Right

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Cylinder bank 1 to 4:

NOTE: To tighten down screws on VANOS gear: Use special tool 11 7 200.

Tighten down six accessible bolts (three on exhaust side and three on inlet side) on VANOS gear to 10 Nm.

Then slacken all six bolts again by a 1/4 turn.

Fig 44: Tightening Bolts On Vanos Gear

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Cylinder bank 1 to 4:

Install all bolts. Alternately tighten down bolts in 1/2 turn increments carefully and evenly until VANOS adjustment unit rests against timing case cover.

Tighten down all bolts.

Fig 45: Tightening Down All Bolts

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Cylinder bank 5 to 8:

CAUTION: CCW thread!

Install toothed shafts of inlet and exhaust sides.

Fig 46: Installing Toothed Shafts

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Brace against twin surface (1) and release hex head (2).

Tightening torque 10 Nm.

NOTE: Coat all sliding surfaces on toothed shafts with engine oil as lubricant.

Cylinder bank 5 to 8:

Oil is sprayed when splined shafts are pressed back. Cover bore (1) with a cloth.

Connect special tool 12 6 050 in conjunction with special tool 12 6 411 to solenoid valves of VANOS adjustment unit.

Fig 47: Connecting Special Tool

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Connect special tool 12 6 411 to correct terminals on car battery.

Press button 2 on special tool 12 6 050 and simultaneously press back toothed shaft of exhaust side by hand up to stop.

Press button 4 on special tool 12 6 050 and simultaneously press back toothed shaft of inlet side by hand up to stop.

Cylinder bank 5 to 8:

Replace O-rings (1 and 2) on VANOS adjustment unit.

Coat O-rings (1) with oil as anti-friction agent.

CAUTION: O-rings (2) fall out very easily, secure with grease if necessary.

Fig 48: Replacing O-Rings

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Cylinder bank 5 to 8:

Rotate spline hubs (1) of inlet and exhaust camshafts to right stop.

Fig 49: Rotating Spline Hubs

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Cylinder bank 5 to 8:

Attach VANOS adjustment unit.

Fig 50: Attaching VANOS Adjustment Unit

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Cylinder bank 5 to 8:

CAUTION: Ensure that both VANOS splined shafts remain in initial position during assembly procedure.

Rotate splined shafts of inlet and exhaust sides until straight splines are engaged.

Push VANOS adjustment unit with splined shaft into VANOS gear until helical cut splines (2) are positioned shortly before meshing with spline hub (1).

Fig 51: Pushing In VANOS Adjustment Unit

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Cylinder bank 5 to 8 (exhaust side):

If the helical cut splines cannot be pushed into the spline hub (1):

Place special tool 11 7 150 on bore in spline hub (1). Rotate spline hub (1) against direction of rotation until splined shaft (2) is positioned with spline hub (1) exactly "tooth-to-tooth gap".

CAUTION: The "first" fitting tooth must snap into place.

Fig 52: Rotating Spline Hub

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Cylinder bank 5 to 8 (inlet side):

Place special tool 11 7 150 on bore in spline hub (1). Rotate spline hub (1) against direction of rotation until splined shaft (2) is positioned with spline hub (1) exactly "tooth-to-tooth gap".

Fig 53: Rotating Spline Hub

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CAUTION: The "first" fitting tooth must snap into place.

Cylinder bank 5 to 8 (inlet side):

Align radial piston pump to driver on spline hub.

NOTE: Picture shows a schematic representation.

Fig 54: Aligning Radial Piston Pump To Driver

Courtesy of BMW OF NORTH AMERICA, INC.

Cylinder bank 5 to 8:

Push on VANOS adjustment unit only until O-rings of VANOS adjustment unit rest against timing case cover.

CAUTION: If this position is not reached, realign position of radial piston pump to driver.

Fig 55: Inserting Bolts On Left And Right

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Cylinder bank 5 to 8:

NOTE: To tighten down screws on VANOS gear: Use special tool 11 7 200.

Tighten down six accessible bolts (three on exhaust side and three on inlet side) on VANOS gear to 10 Nm.

Then slacken all six bolts again by a 1/4 turn.

Fig 56: Tightening Down Screws

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Cylinder bank 5 to 8:

Install all bolts. Alternately tighten down bolts in 1/2 turn increments carefully and evenly until VANOS adjustment unit rests against timing case cover.

Tighten down all bolts.

Fig 57: Tightening Down All Bolts

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Remove special tool 11 2 300.

Fig 58: Removing Special Tool

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CAUTION: The camshafts remain locked in position with special tool 11 7 120.

Carefully rotate engine at central screw against direction of rotation until there is noticeable resistance and spline hubs are at the stop.

NOTE: This procedure creates compensation for play. Only with this compensation for play is the timing diagram correctly set.

Then crank engine again in direction of rotation until 1st cylinder is at TDC firing position.

Secure vibration damper in position with special tool 11 2 300.

Fig 59: Securing Vibration Damper

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Cylinder bank 5 to 8:

NOTE: To tighten down screws on VANOS gear: Use special tool 11 7 200.

Tighten down six accessible bolts (three on exhaust side and three on inlet side) on VANOS gear to 10 Nm.

Fig 60: Tightening Down Screws On Vanos Gear

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Cylinder bank 1 to 4:

NOTE: To tighten down screws on VANOS gear: Use special tool 11 7 200.

Tighten down six accessible bolts (three on exhaust side and three on inlet side) on VANOS gear to 10 Nm.

Fig 61: Tightening Down Accessible Bolts

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Cylinder bank 1 to 4:

Remove special tool 11 7 120.

Fig 62: Removing Special Tool

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Cylinder bank 5 to 8:

Remove special tool 11 7 120.

Fig 63: Removing Special Tool

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Remove special tool 11 2 300. Crank engine at central bolt in direction of rotation a further revolution up to overlap TDC position.

Cylinder bank 5 to 8:

NOTE: To tighten down screws on VANOS gear: Use special tool 11 7 200.

Tighten down remaining six bolts on VANOS gear to 10 Nm.

Fig 64: Tightening Down Screws On VANOS Gear

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Cylinder bank 1 to 4:

NOTE: To tighten down screws on VANOS gear: Use special tool 11 7 200.

Tighten down remaining six bolts on VANOS gear to 10 Nm.

Fig 65: Tightening Down Remaining Bolts

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Rotate crankshaft in direction of rotation as far as ignition TDC position of cylinder 1. Secure vibration damper in position with special tool 11 2 300.

Fig 66: Securing Vibration Damper

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Cylinder bank 1 to 4:

Check camshaft adjustment.

Fig 67: Checking Camshaft Adjustment

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NOTE: Groove on 1st bearing cap is a little wider than groove in camshaft.

Groove on inlet and exhaust camshafts must be located inside groove on 1st bearing cap.

Cylinder bank 5 to 8:

Check camshaft adjustment.

Fig 68: Checking Camshaft Adjustment

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NOTE: Groove on 1st bearing cap is a little wider than groove in camshaft.
Groove on inlet and exhaust camshafts must be located inside groove on 1st bearing cap.

If necessary, adjust camshaft timing. Refer to 11 31 505 ADJUSTING CAMSHAFT TIMING (S62) .

Remove special tool 11 2 300.

Fig 69: Removing Special Tool

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Cylinder bank 5 to 8:

Replace sealing rings.

Fit oil line to VANOS adjustment unit.

Fig 70: Fitting Oil Line

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Tightening torque, 13 Nm.

Cylinder bank 1 to 4:

Remove special tool 11 7 130 from VANOS adjustment unit.

Replace sealing rings.

Attach oil line to VANOS adjustment unit.

Fig 71: Attaching Oil Line

Courtesy of BMW OF NORTH AMERICA, INC.

Tightening torque, 13 Nm.

Assemble engine.

CAUTION: There is air in the VANOS system once it is opened.

In the first few seconds after startup this results in a clearly discernible "rattling noise".

This rattling noise does "not" indicate incorrect assembly.

The rattling noise will disappear as soon as the oil pressure has built up and the system has vented.