11 21 531 Replacing all crankshaft main bearings (N54)

WARNING: This page is about a different car, the 2010 BMW X6, 2009 BMW X6, and 2008 BMW X6. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

00 2 590
11 4 470
11 8 510

See MAINTENANCE AND GENERAL INFORMATION - SPECIAL TOOLS .

See ENGINE - SPECIAL TOOLS (N54, N63) .

IMPORTANT: 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 crankshaft

Check setting of oil spray nozzles, adjusting if necessary:

Attach special tool 11 8 510 to bolt connection on main bearing and secure with bolt (1).

Installation:

Oil nozzle must be located precisely in groove of special tool 11 8 510 .

If necessary, adjust oil nozzle.

Fig 1: Identifying Special Tool 11 8 510 And Bolt

Courtesy of BMW OF NORTH AMERICA, INC.

Adjust oil nozzle.

Release screw (1).

Tightening torque 11 11 5AZ , see 11 11 ENGINE BLOCK

Fig 2: Identifying Screw (1)

Courtesy of BMW OF NORTH AMERICA, INC.

Remove bearing shells (2) and (3).

NOTE: Guide bearing shell (3) is a thrust bearing.

Observe bearing classification.

Fig 3: Identifying Bearing Shells

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

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

Bearing shell (2) without lubricant groove must be fitted in crankcase lower section (bedplate).

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

Fig 4: Identifying Bearing Shell

Courtesy of BMW OF NORTH AMERICA, INC.

Main bearing classification (1) for crankcase lower half (bedplate), code numbers 1 2 3, see table.

Observe bearing classification.

Bearing classification (2) of connecting rods code letters b and r.

Fig 5: Identifying Main Bearing Classification

Courtesy of BMW OF NORTH AMERICA, INC.

Main bearing classification (1) in crankcase, code letters A/B or C, see table.

Installation:

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

Fig 6: Identifying Main Bearing Classification In Crankcase, Code Letters A/B Or C

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

The letter/number combination produces a bearing shell pairing.

Identification by different colors.

IMPORTANT: First bearing point is on the timing drive.
The color combination Yellow and Red must not be fitted.
Engine damage will result if excessively small bearing play is determined.

Code letters on crankcase:

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

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

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

Code numbers on crankshaft:

Code number 1 = bearing shell (2) Yellow.

Code number 2 = bearing shell (2) Green.

Code number 3 = bearing shell (2) Red.

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

Installation example:

For bearing 1 with code letter A on the crankcase and code number 1 on the crankshaft bearing shell (1) with the color Yellow is required for the crankcase and bearing shell (2) with the color Yellow for the crankcase lower half (bedplate).

Bearing 2: A and 2 colors Yellow and Green.

Bearing 3: B and 2 colors Green and Green.

Bearing 4: C and 2 colors Red and Green.

Bearing 5: B and 1 colors Green and Yellow.

Bearing 6: C and 3 colors Red and Red.

Bearing 7: C and 1 colors Green and Green.

The color combination Yellow and Red must not be fitted.

Fig 7: Identifying Bearing

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Possible color combinations for mounting the crankshaft in the crankcase.

CRANKSHAFT COLOR COMBINATIONS REFERENCE CHART

(A 1) Crankcase/Yellow	(B 1) Crankcase/Green	(C 1) Crankcase/Green
(A 1) Crankcase lower half/Yellow	(B 1) Crankcase lower half/Yellow	(C 1) Crankcase lower half/Green

(A 2) Crankcase/Yellow	(B 2) Crankcase/Green	(C 2) Crankcase/Red
(A 2) Crankcase lower half/Green	(B 2) Crankcase lower half/Green	(C 2) Crankcase lower half/Green

(A 3) Crankcase/Green	(B 3) Crankcase/Green	(C 3) Crankcase/Red
(A 3) Crankcase lower half/Green	(B 3) Crankcase lower half/Red	(C 3) Crankcase lower half/Red

Insert all bearing shells (2 and 3).

IMPORTANT: Clean sealing surfaces.
Do not clean sealing faces with a metal-cutting tool.

Clean sealing faces with special tool 11 4 470 only.

Determine bearing play with special tool 00 2 590 .

Installation:

All measuring points must be free from oil and grease.

Use used screws to determine bearing play.

Fig 8: Installing Bearing Shells And Crankshaft

Courtesy of BMW OF NORTH AMERICA, INC.

Set up crankcase lower section (bedplate) with bearing shells.

Remove crankcase lower section (bedplate).

Read off bearing play at width of flattened plastic thread and measurement scale.

Crankshaft bearing clearance radial.

Installation:

Remove plastic thread.

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

Fig 9: Reading Off Bearing Play At Width Of Flattened Plastic

Courtesy of BMW OF NORTH AMERICA, INC.

Install crankcase lower section (bedplate).

Assemble engine.