Measuring the Crankcase Bores

General
Whenever the crankcase is dismantled in the course of rebuilding the engine, measure the main bearing bores.

Measuring
1. Attach crankcase to engine support P 201 using mounting hardware P 201 b and assemble both housing sections. Lightly tighten all through bolts and four M 8 fastening nuts at bearing 1 (flywheel side) and at bearing 8 (pulley side).





2. Applying light blows with a plastic mallet, align both crankcase sections. The gap at bearing bore 8 must not show any offset whatsoever. Use an internal measuring device to measure bearing bore 8 diagonally and align to max. 0.02 mm.
3. Tighten all through bolts and 4 additional hexagon nuts (M 8) at bearing I and bearing 8 to specified torque.
4. Measure all 8 main bearing bores using an internal measuring device.

If the bearing bores are too narrow, use a standard reamer to ream bores to standard dia. 65.00.

Specified size for bearing bores 1 to 8 is 65.000 mm to 65.019 mm.

5. If the bearing bores are too large, use a roughing or finishing reamer, respectively, to ream to 65.25 mm oversize dia. (B bearings). The checking dimension for B bearings is 65.25 mm dia. to 65.269 mm dia.