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

WARNING: This page is about a different car, the 2005 BMW 530i, 2005 BMW 525i, 2004 BMW 530i, and 2004 BMW 525i. However, it is still accessible from the selected car via links, so may be relevant.

(engine removed)

Necessary preliminary tasks:

Remove Cylinder Head .
Remove lower timing case cover. See 11 14 110 Removing And Installing Lower Timing Case Cover .
Remove all pistons. See 11 25 530 Removing And Installing Or Replacing 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

Courtesy of BMW OF NORTH AMERICA, INC.

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: Unfastening Screw Connection On Reinforcement Plates

Courtesy of BMW OF NORTH AMERICA, INC.

Unfasten screw connection on main bearing.

Remove main bearing caps (1 to 7).

Lever out crankshaft.

Fig 3: Unfastening Screw Connection On Main Bearing

Courtesy of BMW OF NORTH AMERICA, INC.

If necessary, release incremental gear.

Installation:

Replace screws.

Install screws and tighten down in two passes.

Tightening torque, see 11 21 1AZ in ENGINE - TIGHTENING TORQUES .

IMPORTANT: Check grinding stage of crankshaft.

Fig 4: Checking Grinding Stage Of Crankshaft

Courtesy of BMW OF NORTH AMERICA, INC.

Replace main crankshaft bearing shells. See 11 21 531 Replacing All Main Crankshaft Bearing Shells .

Replace Conrod Bearing Shells .

Replace grooved ball bearings in crankshaft.