Figuring Out Crankcase and Crankshaft Metrology

[tshaw]

Dear all,
I am figuring out the airworthiness of a Continental A65 Crankcase, CrankShaft and CamShaft, from the metrology point of view.
Looking at the literature we find the table of limits as shown below.
Most of the limits are given in looseness (L) or tightness (T) limits.
For instance, there shall be a maximum of 0.005L gap in the crankshaft front main bearing (Ref 8a)
Taking the outside diameter of a crank or camshaft journal is straight forward. Have a calibrated micrometer and its done.
However, taking the inner diameter of a crankcase main bearing or camshaft bearing seem not that easy.
The bearings should be snapped into the crankcase, the crankcase closed and bolts torqued, without the crankshaft and camshaft.
Then, using a subito (inner dia comparison) or equivalent instrument we should verify the bearings dia, subtract the correspondent journal dia and find if it is within the serviceable limits.
Well, front and rear bearings are easier because they are within easy reach but center bearings are more difficult.
Does anyone have experience with this issue?
Does my "draft procedure" makes sense?

Thanks for advise.
Tom Shaw

 

[bob turner]

 

[fastmax4]

 

[tshaw]