Checking main bearing clearance

To check crankshaft bearing clearance, use the existing main bearing screws.

Fig 1: Checking Main Bearing Clearance

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Do not twist crankshaft.

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

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

Tightening torque 11 11 1AZ, see 11 11 ENGINE BLOCK

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 to angle of rotation.

Fig 3: Tightening Collar Bolt

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Remove main bearing cap.

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

Main bearing play  .

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

Fig 4: Checking Main Bearing Play

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Install crankshaft  .

Carefully strike back and front of crankshaft with a plastic hammer to center thrust 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 (axial play  ).

Check guide bearing shell, crankshaft and crankcase if necessary.

Fig 5: Checking Crankshaft End Play

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Assemble engine.