11 24 571 Replacing all conrod bearings (M57T2)

Necessary preliminary tasks:

IMPORTANT: The connecting rod bearing shells for the connecting rod and the connecting rod bearing cap are different.
Replace connecting rod bolts.

Install the normal conrod bearing shell (low version red) in the conrod bearing cap.

Fig 1: Identifying Normal Connecting Rod Bearing Shell

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Install the more wear-resistant "S" conrod bearing shell (high version blue) in the conrod.

Fig 2: Identifying Wear-Resistant "S" Connecting Rod Bearing Shell

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Insert one blue and one red bearing shell for each connecting rod (irrespective of the colour coding on the connecting rod shaft).

IMPORTANT: Note grinding stages on crankshaft.

Fig 3: Locating Bearing Shell Of Connecting Rod

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Install piston.

Check connecting rod bearing clearance.

Piston in BDC position.

Place special tool 00 2 590 (Plastigage model PG 1) on oil-free crankshaft.

Fit bearing caps so that pair numbers match up.

Fig 4: Locating Bearing Caps Matching Numbers

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IMPORTANT: Do not turn the connecting rods or crankshaft.

Use the old connecting rod bolts to check connecting rod clearance.

Tighten down connecting rod bolts with special tool 00 9 120.

Tightening torque, see 11 24 1AZ in CONNECTING RODS AND BEARINGS .

Fig 5: Tightening Connecting Rod Bolt Using Special Tool (00 9 120)

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Remove bearing caps.

Read off bearing clearance at width of crushed plastic thread with aid of measuring scale.

Conrod bearing clearance.

Remove plastic thread.

Fig 6: Locating Bearing Clearance Reading On Crushed Plastic Thread (Plastigage)

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Summary:

Colour code/shaft diameter/bearing strength

Rt = red

Bl = blue

Fig 7: Identifying Bearing Clearance

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Assemble engine.