11 24 571 Replacing all connecting rod bearing shells (N52K)

WARNING: This page is about a different variant/trim than selected.

IMPORTANT: All crank pins are connected with the crankshaft.
Modified procedure: The colors of the connecting rod bearing shells are the same at the top and bottom.
The Blue/Red connecting rod bearing shell colors are no longer fitted in combination.

Necessary preliminary tasks:

Remove OIL SUMP

IMPORTANT: All crankshaft crank pins are classified.

Possible classifications per connecting rod at top and bottom:

r: Red

b: Blue

Only one color may be fitted per big end bearing cap and connecting rod.

In direction of arrow from (1 to 2) crank pin (1 to 6).

Fig 1: Direction Of Fitting Color In Connecting Rod And Connecting Rod Bearing Cap

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Example:

Possible classification: rbbrrb

Cylinder 1: Classification Red/Red

Cylinder 2: Classification Blue/Blue

Cylinder 3: Classification Blue/Blue

Cylinder 4: Classification Red/Red

Cylinder 5: Classification Red/Red

Cylinder 6: Classification Blue/Blue

Release connecting rod bolts (1).

Remove connecting rod bearing cap (2).

Fig 2: Identifying Connecting Rod Bearing Cap And Connecting Rod Bolts

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IMPORTANT: Risk of damage to cylinder wall and to crankshaft.

Gently release connecting rod from crankshaft.

Remove connecting rod bearing shells (1 and 2).

Install new connecting rod bearing shells.

Installation:

Pay attention to guide lugs during installation.

Fig 3: Identifying Connecting Rod Bearing Shells

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IMPORTANT: All crankshaft crank pins are classified.

In each case insert only one color of connecting rod bearing shell (1 and 2) for each connecting rod.

Check connecting rod bearing clearance.

Piston in BDC position.

To determine the connecting rod bearing play, make sure that the bearing points are clean and free from oil and grease.

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

Fit connecting rod bearing cap so that pairing letters match up.

Fig 4: Locating Bearing Cap Pairing Letters

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IMPORTANT: Do not distort 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 11 24 1AZ .

Fig 5: Adjusting Connecting Rod Torsion Angle Using Special Tool 00 9 120

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Unscrew connecting rod bearing cap. Read off connecting rod bearing play at width of flattened plastic thread on measurement scale.

Connecting rod bearing play. See TED-TED-TDMUC1124-N52K-01B1S2 CONNECTING RODS AND BEARINGS N52K/B30 or TED-TED-TDMUC1124-N52K-01B1S1 CONNECTING RODS AND BEARINGS N52K/B25

Remove Plastigage
Coat crankshaft and connecting rod bearing shells with oil
Install new connecting rod bolts and tighten down with special tool 00 9 120.

Fig 6: Checking Bearing Clearance Width Of Crushed Plastic Thread (Plastigage)

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Tightening torque 11 24 1AZ .

Assemble engine.