Checking main bearing clearance

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

Do not twist crankshaft.

Place special tool 00 2 590 (Plastigage model PG 1) onto the oil-free crankshaft (see arrow in illustration).

Fig 1: Locating Main Bearing Clearance On Crankshaft

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

Tightening torque 11 11 1AZ .

Fig 2: Crankshaft Bolts (M11) Tightening/Loosening Sequence

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

Fig 3: Tightening All Collar Bolts (M11) Of Main Bearing Caps Using Special Tool (00 9 120)

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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 - TECHNICAL DATA .

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

Fig 4: Checking Main Bearing Clearance At Width Of Flattened Plastic Thread (Plastigage)

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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 5: Checking Crankcase Side Clearance

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Assemble engine.