11 21 500 Replacing crankshaft (M52 / S52 / M52TU / M54 / M56)

WARNING: This page is about a different car, the 2003 BMW 525i, 2002 BMW 525i, and 2001 BMW 525i. However, it is still accessible from the selected car via links, so may be relevant.

(engine removed)

Necessary preliminary tasks:

Removing cylinder head
Removing lower timing case cover
Removing all pistons
Remove end cover at rear; this operation is described in the section Replacing crankshaft radial seal.

Checking axial clearance:

If permitted end float is exceeded, check crankshaft, guide bearing shells and engine block, replacing if necessary, end float.

Fig 1: Checking Axial Clearance

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Unfasten screw connection on reinforcement plates.

NOTE: The reinforcement plates are not fitted on engines with gray cast iron engine blocks or on engines with oil pumps integrated in oil scrapers.

Fig 2: Identifying Screws On Reinforcement Plates

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Unfasten screw connection on main bearing.

Remove main bearing caps (1 to 7).

Lever out crankshaft.

Fig 3: Identifying Main Bearing Caps

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If necessary, release incremental gear.

Installation:

Replace screws.

Install screws and tighten down in two passes.

Tightening torque. Refer to ENGINE - TIGHTENING TORQUES .

IMPORTANT: Check grinding stage of crankshaft.

Fig 4: Identifying Crankshaft Mark

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Replace main crankshaft bearing shells.

Replace conrod bearing shells.

Replace grooved ball bearings in crankshaft.