11 21 531 Replacing All Crankshaft Main Bearings (N54): Notes

WARNING: This page is about a different car, the 2010 BMW 135i, 2009 BMW 135i, and 2008 BMW 135i. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

For the following special tools, refer to MAINTENANCE AND GENERAL INFORMATION - SPECIAL TOOLS .

00 2 590

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

11 4 470
11 8 510

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 . See 11 21 500 REPLACING CRANKSHAFT (N54) .

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: Locating Oil Nozzle In Groove Of Special Tool 11 8 510

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Adjust oil nozzle.

Release screw (1).

Tightening torque. See 11 11 5AZ in 11 11 ENGINE BLOCK .

Fig 2: Identifying Screw

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Remove bearing shells (2) and (3).

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

Fig 3: Identifying Bearing Shells

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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 Shells

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

Observe bearing classification . See ENGINE - TECHNICAL DATA .

Bearing classification (2) of connecting rods code letters b and r. See 11 24 571 REPLACING ALL CONNECTING ROD BEARINGS (N54) .

Fig 5: Identifying Main Bearing Classification Number On Crankcase Lower Half (Bedplate)

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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

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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.