11 21 531 Replacing all crankshaft main bearing shells (N63) without hybrid drive

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Special tools required:

IMPORTANT: Risk of injury from sharp edge of housing.

IMPORTANT: If a crankcase or a crankshaft is replaced, old and new identifications can be used.
A mixed installation is permissible.
Example:
An old crankcase with an old crankcase designation and a new crankshaft with a new crankshaft designation.
An old crankshaft with an older crankshaft designation and a new crankcase with a new crankcase designation.
Or a new crankcase with a new crankshaft with new identifications.

Necessary preliminary work:

Remove CRANKSHAFT .

NOTE: The main bearing caps 1 to 5 are marked with numbers.

Fig 1: Identifying Main Bearing Caps Marked With Numbers

Courtesy of BMW OF NORTH AMERICA, INC.

Observe crankshaft construction stage:

S: Series
B: Repair stage 1
C: Repair stage 2

The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 (main bearing cap).

The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment on crankshaft 1 to 5

Y= yellow
G= green
V= violet

Fig 2: Identifying Color Assignment On Crankshaft
Courtesy of BMW OF NORTH AMERICA, INC.

The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 in the crankcase and is located on the transmission side in the Vee. The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment in crankcase 1 to 5.

Y= yellow
G= green
V= violet

Fig 3: Identifying Color Assignment On Crankshaft
Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: New bearing shell classification.

The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 (main bearing cap).

The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment on crankshaft 1 to 5

Fig 4: Identifying Color Assignment On Crankshaft

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Changed bearing classification:
Bearing position 1, 2, 3, 4 and 5

Code letter	Color code
New (A to H) Old Y	Yellow Yellow
New (I to R) Old G	Green Green
New (S is Z) Old V	Violet

	Tolerance classes	Bearing shell covers
Crankcase	A	Yellow
	B	Yellow
	C D E G H
Crankcase	I	Green
	C	Green
	M N P q R
Crankcase	S	Violet
Crankcase	T U W X Z
Crankshaft	A	Yellow
	B	Yellow
	C D E G H
Crankshaft	I	Green
	C	Green
	M N P q R
Crankshaft	S	Violet
Crankshaft	T U W X Z

Installation note:

Install main bearing shells (1) with lubrication groove in crankcase.

Install main bearing shells (2) without lubrication groove in the main bearing caps.

Fig 5: Identifying Main Bearing Shells (With And Without Lubrication Groove)

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Main bearing cap number 3 can be identified by the surfaces (1) for the thrust washers of the thrust bearing.

Fig 6: Identifying Thrust Bearing Surface

Courtesy of BMW OF NORTH AMERICA, INC.

Turn back thread support bushing into main bearing cap.

Fig 7: Turning Back Thread Support Bushing Into Main Bearing Cap

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Checking main bearing clearance

To check crankshaft bearing play, use the existing main bearing bolts.

IMPORTANT: Risk of cracking!

No oil is permitted in the blind holes.

Do not twist crankshaft.

Place special tool 00 2 590 (Plastigage model PG 1) onto the oil-free crankshaft (see arrow).

Fig 8: Locating Main Bearing Clearance On Crankshaft

Courtesy of BMW OF NORTH AMERICA, INC.

Tighten down all collar bolts (M11) of main bearing caps in sequence 1 to 5 to joining torque.

Tightening torque 11 11 1AZ .

Fig 9: Crankshaft Bolts (M11) Tightening/Loosening Sequence

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Tighten down all collar bolts (M11) of main bearing caps with special tool 00 9 120 with angle of rotation.

Fig 10: Tightening All Collar Bolts (M11) Of Main Bearing Caps Using Special Tool (00 9 120)

Courtesy of BMW OF NORTH AMERICA, INC.

Remove main bearing cap.

Read off main bearing clearance at width of flattened plastic thread with assistance of measurement scale.

Main bearing clearance See CRANKSHAFT AND BEARINGS .

Remove plastic thread
Apply a coat of oil to new bearing shells and crankshaft

Fig 11: Checking Main Bearing Clearance At Width Of Flattened Plastic Thread (Plastigage)
Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Always replace main bearing bolts in main bearing caps with new bolts.
Do not wash off bolt coating.

IMPORTANT: Risk of cracking!
No oil is permitted in the blind holes.

Install CRANKSHAFT .

Carefully strike back and front of crankshaft with a plastic hammer to center guide bearing (do not damage crankshaft).

Secure special tool 11 6 252 with magnetic foot on crankcase.

Position special tool 11 6 251 .

Tightening specifications for main bearing:

Check SIDE CLEARANCE .

Check guide bearing shell, crankshaft and crankcase if necessary.

Fig 12: Checking Crankcase Side Clearance

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.