11 21 531 Replacing all crankshaft main bearing (N55)

WARNING: This page is about a different car, the 2013 BMW X5, 2012 BMW X5, and 2011 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

Necessary preliminary tasks:

Remove CRANKSHAFT .

Checking position of oil spray nozzles:

Check position of oil spray nozzle according to position on special tool 11 8 510 .

Insert special tool 11 8 510 into main bearing screw connection and secure from turning with screw (1).

Fig 1: Inserting Special Tool 11 8 510 Into Main Bearing Screw Connection

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If necessary, adjust oil spray nozzles and secure.

Tighten banjo bolt (1).

Tightening torque: 11 11 5AZ .

Fig 2: Identifying Banjo Bolt

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Installation note:

Bearing shell (1) with lubricating groove must be fitted in upper section of crankcase.

Bearing shell (2) without lubricating groove must be installed in lower section of crankcase.

Fig 3: Identifying Bearing Shell (With And Without Lubricating Groove)

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IMPORTANT: Allocation of bearing positions:
Bearing position 1 is at the front on the timing chain drive in the direction of travel.

Main bearing classification (1) in crankcase.

Installation note:

When all the letters and number code have been determined, the bearing shell color must be allocated, see chart below.

Fig 4: Identifying Bearing Classification Code In Crankcase

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Main bearing classification:

Code letters A/B or C) are used for the crankcase upper section.

For bearing seat assignment from 1 to 7, the first bearing position is indicated by a star (1) on timing drive.

Fig 5: Identifying Bearing Seat Assignment Code

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Main bearing classification:

ID codes 1/2 or 3) are used for crankcase lower section.

For bearing seat assignment (1) from 1 to 7, the first bearing position is located on timing drive.

NOTE: Code letters (2) are required exclusively for classifying CONNECTING ROD BEARING .

Fig 6: Identifying Connecting Rod Bearing Code Letters

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Observe bearing classification. See 1121 CRANKSHAFT AND BEARINGS (N55) .

Installation note:

The letter/number combination produces a bearing shell pairing.

Identification by different colors.

IMPORTANT: First bearing position is on the timing drive.
Engine damage will result if an insufficiently small radial clearance is determined.
If a large radial clearance is determined, this can lead to noises in crankshaft drive.

Code letters on crankcase:

Code letter A = bearing shell (1) color Yellow with lubricating groove.

Code letter B = bearing shell (1) color Green with lubricating groove.

Code letter C = bearing shell (1) color Red with lubricating groove.

Code numbers on crankshaft:

Fig 7: Identifying Bearing Shell With Code Letter

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Code number 1 = bearing shell (2) Yellow without lubricating groove.

Code number 2 = bearing shell (2) Green without lubricating groove.

Code number 3 = bearing shell (2) Red without lubricating groove.

IMPORTANT: The color set Yellow and Red must not be fitted; the bearing colors Green/Green must be selected for this color set.

Installation note:

Possible color combinations for mounting the crankshaft in the crankcase.

Installation example:

For bearing 1 with code letter B on crankcase and code letter 1 on crankshaft , the bearing shell (1) with the color Green is required for the crankcase upper section and bearing shell (2) with the color Yellow for the crankcase lower section (bedplate).

Fig 8: Identifying Bearing Shell Code Number

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Bearing 2: B and 2 colors Green and Green.

Bearing 3: A and 2 colors Yellow and Green.

Bearing 4: B and 2 colors Green and Green.

Bearing 5: A and 1 colors Yellow and Yellow.

Bearing 6: B and 3 colors Green and Red.

Bearing 7: B and 1 colors Green and Yellow.

IMPORTANT: The color set Yellow and Red must not be fitted; the bearing colors Green/Green must be selected for this color set.

(A 1) Crankcase/Yellow	(B 1) Crankcase/Green	(C 1) Crankcase/Green
(A 1) Crankcase lower section/Yellow	(B 1) Crankcase lower section/Yellow	(C 1) Crankcase lower section/Green
(A 2) Crankcase/Yellow	(B 2) Crankcase/Green	(C 2) Crankcase/Red
(A 2) Crankcase lower section/Green	(B 2) Crankcase lower section/Green	(C 2) Crankcase lower section/Green
(A 3) Crankcase/Green	(B 3) Crankcase/Green	(C 3) Crankcase/Red
(A 3) Crankcase lower sections/Green	(B 3) Crankcase lower section/Red	(C 3) Crankcase lower section/Red

NOTE: Guide bearing shell (1) at bearing seat 4 is a thrust bearing.

Observe bearing classification . See 1121 CRANKSHAFT AND BEARINGS (N55) .

Fig 9: Identifying Guide Bearing Shell

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IMPORTANT: Do not use any metal-cutting tools.
Only use special tool 11 4 470 to clean sealing surfaces.

Installation note:

Clean all sealing surfaces.

Install bearing shells (2) and guide bearing shell (3).

Fig 10: Installing Bearing Shells And Guide Bearing Shell

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Installation note:

If a radial clearance needs to be redetermined, use special tool 00 2 590 to do this.

Installation note:

All measuring points must be clean and free from oil and grease. If necessary, clean all measuring points.

The old bearing screws can be used to determine the radial clearance.

Set up CRANKCASE LOWER SECTION with bearing shells.

Remove crankcase lower section.

Read off radial clearance . See 1121 CRANKSHAFT AND BEARINGS (N55) at width of flattened Plastigage and measuring scale.

Installation note:

Remove Plastigage.

Apply a light coat of oil to bearing shells and crankshaft.

Fig 11: Checking Radial Clearance

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Fit CRANKCASE LOWER SECTION .

Assemble engine.