BMW 7 Series: Replacing All Crankshaft Main Bearing Shells (N63) Without Hybrid Drive

Notes

IMPORTANT: Risk of injury from sharp edge of housing.

IMPORTANT: If a crankcase or a crankshaft is replaced, old and new identifications can be used.

A mixed installation is permissible.

Example:

An old crankcase with an old crankcase designation and a new crankshaft with a new crankshaft designation.

An old crankshaft with an older crankshaft designation and a new crankcase with a new crankcase designation.

Or a new crankcase with a new crankshaft with new identifications.

Necessary preliminary work

• Remove CRANKSHAFT

NOTE: The main bearing caps 1 to 5 are marked with numbers.

Fig. 105: Identifying Main Bearing Caps Marked Numbers

Observe crankshaft construction stage:

S: Series
B: Repair stage 1
C: Repair stage 2

The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 (main bearing cap).

The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment on crankshaft 1 to 5

Y= yellow
G= green
V= violet

Fig. 106: Identifying Color Assignment On Crankshaft 1 To 5

The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 in the crankcase and is located on the transmission side in the Vee. The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment in crankcase 1 to 5.

Y= yellow
G= green
V= violet

Fig. 107: Identifying Color Assignment In Crankcase 1 To 5

IMPORTANT: New bearing shell classification.

The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 (main bearing cap).

The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment on crankshaft 1 to 5

Fig. 108: Identifying Color Assignment On Crankshaft 1 To 5

IMPORTANT: Changed bearing classification: Bearing position 1, 2, 3, 4 and 5

BEARING SHELL CLASSIFICATION LETTER WITH CODE

TOLERANCE CLASSES AND BEARING SHELL COVERS COLOR CODE REFERENCE CHART

Installation note: Install main bearing shells (1) with lubrication groove in crankcase.

Install main bearing shells (2) without lubrication groove in the main bearing caps.

Fig. 109: Identifying Main Bearing Shells

NOTE: Main bearing cap number 3 can be identified by the surfaces (1) for the thrust washers of the thrust bearing.

Fig. 110: Identifying Main Bearing Cap Thrust Washers Surfaces

Turn back thread support bushing into main bearing cap.

Fig. 111: Turning Back Thread Support Bushing Into Main Bearing Cap

Checking main bearing clearance

To check crankshaft bearing play, use the existing main bearing bolts.

IMPORTANT: Risk of cracking! No oil is permitted in the blind holes.

Do not twist crankshaft.

Place special tool 00 2 590

(Plastigage model PG 1) onto the oil-free crankshaft (see arrow).

Fig. 112: Identifying Main Bearing Clearance On Crankshaft

Tighten down all collar bolts (M11) of main bearing caps in sequence 1 to 5 to jointing torque.

Tightening torque 11 11 1AZ.

Fig. 113: Identifying Main Bearing Caps Collar Bolts Tightening Sequence

Tighten down all collar bolts (M11) of main bearing caps with special tool 00 9 120 with angle of rotation.

Fig. 114: Tightening Collar Bolts (M11) Of Main Bearing Caps With Special Tool 00 9 120 With Angle Of Rotation

Remove main bearing cap.

Read off main bearing clearance at width of flattened plastic thread with assistance of measurement scale.

Main bearing clearance: See CRANKSHAFT AND BEARINGS or CRANKSHAFT AND BEARINGS.

• Remove plastic thread
• Apply a coat of oil to new bearing shells and crankshaft

Fig. 115: Measuring Main Bearing Clearance

NOTE: Always replace main bearing bolts in main bearing caps with new bolts.

Do not wash off bolt coating.

IMPORTANT: Risk of cracking! No oil is permitted in the blind holes.

Install CRANKSHAFT.

Carefully strike back and front of crankshaft with a plastic hammer to center guide bearing (do not damage crankshaft).

Secure special tool 11 6 252 with magnetic foot on crankcase.

Position special tool 11 6 251.

Tightening specifications for main bearing: Check SIDE CLEARANCE.

Check guide bearing shell, crankshaft and crankcase if necessary.

Fig. 116: Checking Side Clearance

Assemble engine.

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