Measuring radial bearing play
Measure main bearing journal with an external micrometer in two planes, A and B at right angles.
Enter measured values on record sheet. See Technical Data.
Caution!
- The crankshaft can only be reground in grinding stage 0; after this it must be rehardened and finished. Grinding stages are identified by a paint mark on the front crank web. See Technical Data.
- When replacing the bearing shells, make sure that the colour marks on the crankpins and big end bearings match.
Installing main bearings
Insert tensioner rail/slide rail pivot pin (1) for centering purposes.
Tighten M8 and M10 crankcase screws.
Tightening torque/tightening order:
- 1. M10 screw (oiled):
- Initial torque — 25 Nm
- Wrench angle — 90°
- 2. M8 screw (oiled) — 22 Nm
Measure front and rear bearings in the load direction.
Enter measured values on record sheet and calculate main bearing play. See Technical Data.
Measuring axial bearing play
Place crankshaft in crankcase.
Insert tensioner rail/slide rail pivot pin (1) for centering purposes.
Tighten crankcase screws.
Screw measuring device, BMW # 00 2 500, with dial gauge, BMW # 00 2 510, in tapped hole for alternator carrier cover.
Move crankshaft forwards and backwards and read axial play from dial gauge. See Technical Data.