11 12 100 Removing And Installing Cylinder Head (N52K)

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Special tools required:

For the following special tools, refer to ENGINE- SPECIAL TOOLS (N52K) .

11 0 320
11 4 420
11 4 430
11 4 471
11 4 472
11 8 580

IMPORTANT: Aluminum-magnesium materials. No steel screws/bolts may be used due to the threat of electrochemical corrosion. A magnesium crankcase requires aluminum screws/bolts exclusively. Aluminum screws/bolts must be replaced each time they are released. Aluminum screws/bolts are permitted with and without color coding (blue). For reliable identification: Aluminum screws/bolts are not magnetic . Jointing torque and angle of rotation must be observed without fail (risk of damage) .

Necessary preliminary tasks:

Remove exhaust system . See EXHAUST SYSTEM COMPLETE .
Drain coolant . See 17 00 005 DRAINING AND ADDING COOLANT (N52, N52K, N51, N53) .
Drain off engine oil. See 11 00... ENGINE OIL SERVICE (N52K) .
Remove both exhaust manifolds . See EXHAUST MANIFOLD WITH .
Remove intake air manifold . See 11 61 050 REMOVING AND INSTALLING AIR INTAKE MANIFOLD (N52K) .
Detach coolant hoses from cylinder head
Remove inlet and exhaust adjustment unit . See 11 36 046 REMOVING AND INSTALLING/REPLACING INLET AND EXHAUST ADJUSTMENT UNITS (N52) .

IMPORTANT: Fit new cylinder head screws. Do not wash off bolt coating. There must be no coolant, water or engine oil in the pocket holes. Risk of corrosion and cracking!

Release screws (1).

Unclip timing chain module (2) at junction (3) and remove towards top.

Set down timing chain.

IMPORTANT: If the timing chain is stowed in the gear case, the crankshaft must no longer be rotated.
This would cause the timing chain on the crankshaft sprocket wheel to jam or jump.

Installation:

The timing chain is lifted out with a hook only during assembly.

Fig 1: Identifying Timing Chain Module At Junction With Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Release bolts (2) for eccentric shaft sensor (1).

Remove eccentric shaft sensor (1) towards front.

Fig 2: Identifying Eccentric Shaft Sensor And Bolts

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Screw (1) is not magnetic and must be secured against falling down.

Release screw (1).

Remove magnet wheel (2) towards front.

Fig 3: Identifying Magnet Wheel And Screw

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Magnet wheel (1) is highly magnetic and must be protected against metal filings/borings.

After removing, place magnet wheel (1) in a plastic bag (2) with a seal.

Fig 4: Identifying Magnet Wheel In Plastic Bag

Courtesy of BMW OF NORTH AMERICA, INC.

Pretension eccentric shaft (1) upwards in direction of arrow.

Remove stop screw between 1st and 2nd cylinders.

Tightening torque. See 11 37 5AZ in 11 37 VARIABLE VALVE GEAR .

Fig 5: Pretensioning Eccentric Shaft Upwards

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Bolt (2) can only be released when the timing chain module is pressed forward slightly.

IMPORTANT: Secure bolt (2) with a gripper against falling down.

Fig 6: [Identifying Timing Chain Module Bolt And Screw]

Courtesy of BMW OF NORTH AMERICA, INC.

Release screw (2).

Tightening torque. See 11 12 3AZ in CYLINDER HEAD WITH COVER .

Release screws (1).

Tightening torque. See 11 12 4AZ in CYLINDER HEAD WITH COVER .

Installation:

Replace aluminum screws.

IMPORTANT: Observe different bolt heads.

Release M10 cylinder head bolts (1) with special tool 11 8 580.

Release M9 cylinder head bolts (2) with special tool 11 4 420.

NOTE: Picture shows inlet and exhaust camshafts removed.

Fig 7: Identifying Special Tool (11 8 580 And 11 4 420)

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Observe different M9 bolt lengths (1 and 3).

Release M9 cylinder head bolts (1 and 3) with special tool 11 4 420.

Tightening torque. See 11 12 2AZ in CYLINDER HEAD WITH COVER .

Release M10 cylinder head bolts (2) with special tool 11 8 580 from outside inwards.

Tightening torque. See 11 12 1AZ in CYLINDER HEAD WITH COVER .

Fig 8: Identifying M9 Cylinder Head Bolts

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: All cylinder head bolts (1, 2 and 3) must be replaced. Joining torque and angle of rotation must be observed without fail.
Risk of damage!

Secure special tool 11 0 320 with existing cylinder head cover bolts (1).

Tightening torque. See 11 12 5AZ in CYLINDER HEAD WITH COVER .

IMPORTANT: Removing and install cylinder head with a second person helping. Weight of cylinder head with add-on parts is approx. 40 kg. Do not rest cylinder head on sealing surface. Risk of damage to valves!

Fig 9: Identifying Special Tool (11 0 320)

Courtesy of BMW OF NORTH AMERICA, INC.

Insert special tool 11 4 430 into bores.

Fig 10: Identifying Special Tool (11 4 430)

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Remove coarse residues on sealing faces with special tool 11 4 471 from cylinder head and crankcase.

IMPORTANT: Do not use any metal-cutting tools.

Fig 11: Identifying Special Tool (11 4 471)

Courtesy of BMW OF NORTH AMERICA, INC.

Remove fine residues on sealing faces with special tool 11 4 472 from cylinder head and crankcase.

IMPORTANT: Do not use any metal-cutting tools. There must be no coolant, water or engine oil in the pocket holes. Risk of corrosion and cracking!

Fig 12: Identifying Special Tool (11 4 472)

Courtesy of BMW OF NORTH AMERICA, INC.

There must be no fluids or contaminants in any of the threaded holes (1) for the cylinder head bolt connections. Risk of cracking and corrosion! - Clean all threaded holes.

Fig 13: Identifying Threaded Hole

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Replace cylinder head gasket. See 11 12 101 REPLACING CYLINDER HEAD GASKET (N52K) .

IMPORTANT: Observe sequence for tightening cylinder head bolts without fail.

Fit new cylinder head screws.

Insert cylinder head bolts (1 to 10) with special tool 11 8 580.

Tightening torque. See 11 12 1AZ in CYLINDER HEAD WITH COVER .

Insert cylinder head bolts (11 to 14) with special tool 11 4 420.

Tightening torque. See 11 12 2AZ in CYLINDER HEAD WITH COVER .

NOTE: Picture shows inlet and exhaust camshafts removed.

Fig 14: Cylinder Head Bolts Tightening/Loosening Sequence

Courtesy of BMW OF NORTH AMERICA, INC.

Observe sequence for tightening cylinder head bolts without fail.

IMPORTANT: The 2nd torsion angle relates only to cylinder head bolts 1 to 10.

Installation:

Tightening torque:
All cylinder head bolts 1 to 14 to 30 Nm
1st angle of rotation:
All cylinder head bolts 1 to 14 to 90°
2nd angle of rotation:
Only cylinder head bolts 1 to 10 to 90°
3rd angle of rotation:
All cylinder head bolts 1 to 14 to 45°

Insert bolts (1).

Tightening torque. See 11 12 4AZ in CYLINDER HEAD WITH COVER .

IMPORTANT: Secure bolt (2) with a gripper against falling down.

Insert bolt (2).

Tightening torque. See 11 12 3AZ in CYLINDER HEAD WITH COVER .

Fig 15: Identifying Timing Chain Module Bolt And Screw

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Replace aluminum screws.

Assemble engine.