11 24 571 Replacing all connecting rod bearings (N47D20 K/U/O/T 1)

Special tools required:

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.

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

IMPORTANT: Note GRINDING STAGES ON CRANKSHAFT .

Fig 1: Locating Connecting Rod Mark And Bearing Shell

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Install piston.

Check connecting-rod bearing play.

Piston in BDC position.

Fit special tool 00 2 590 (Plastigage type PG 1) to oil-free crankshaft.

Fit bearing caps so that matching numbers match up.

Fig 2: 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 bearing play.

00 9 120 Tighten down connecting rod bolts with special tool or special tool.11 2 110

Tightening torque 11 24 1AZ.

Fig 3: Tightening Connecting Rod Bolts Using Special Tool (00 9 120)

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Remove bearing caps.

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

Remove Plastigage.

Fig 4: Checking Connecting Rod Bearing End Play

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Overview:

Color code/shaft diameter/bearing strength

Rt = red

Bl = blue

Crankshaft journal
Bearing clearance
Bearing shells: red or blue
Connecting rods

Fig 5: Identifying Bearing Clearance
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Assemble engine.