I was cleaning up an outer main bearing and I got to wondering what this little hole is for. It's only 1mm or so in depth and there is no matching hole in c/case journal.
There is the large bearing locator hole. The oil injection holes. I have no idea why the little one is there. Anyone know ?
I thought it was to be used as the front case half alignment mark, when setting the crank into lower case, to help align bearing. Just a guess but, I think I noticed one of the times I put a crank in T500 the tiny hole was centered in the case half edge ... coincidence? I did give is much thought beyond that, I have extra engines/cranks and could check again.
I asked Pete Odell about it and he confirms your analysis that the little hole, dead opposite the locator pin hole, is there to aid assembly and align the locator pin hole when you drop a crank into the cases. As simple as that .
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