AT LONG LAST: A REAL BREAKTHROUGH
OK chaps, we all know by now my problem was glass.
But despite my extensive work I could not find / prove where exactly it was hiding in the first place, to do so much (localised) damage.
Well, the hunt is over and for the first time in the last few months I am 100% confident I can put my engine back together without worrying about a recurrence.
The @£$%^& glass beads were hiding inside the top holes (and presumably their connected little galleys) of the crank covers, which as I have now found out to my peril, are not blind.
THEY ARE CONNECTED WITH THE CRANK OIL WAYS. The existence of an 'o' ring there, should ring a bell about it but I missed it ...
Below is the RHS top crank cap hole (No 6 piston side, careful, not talking about the offending no 1 yet)
P1070926.jpg
And look what I got out of it ... and this is after intense cleaning in the degreaser.
P1070949.jpg
In fact and after using compressed air, this hole is still 99% blocked and I plan to look at it more carefully tomorrow to find out 'with what'.
But take a look at the crappy photo below of the crankcase oil way next to it; you can clearly see a piece of glass embedded on to a small 'crack' (or is it a small galley) in it - Amazing.
P1070937.jpg
BTW the LHS hole bore was clean-ish but with no glass to be found near it.
My analysis is not yet complete. But I think I can preliminarily say the following:
1. I made the fatal mistake of assuming these holes were blind, external, and therefore not critical during cleaning. Who knows what I was thinking

. I am sure I cleaned them, but had no reason to insist further for the above reason.
2. The LHS (infamous cylinder no 1 side) hole was full of the glass after my rebuilt, and this was quickly sucked up by the crank by means of the oil flow, and we all know what happened then.
3. The RHS was as bad, but for some reason 99% blocked by who knows what, WHICH AS A RESULT SAVED THAT SIDE!!!
I feel very relieved to have at last a viable proof of exactly what went wrong.
Dave, PLEASE, can you explain to me why these are not blind. I am sure there is a good reason.
Best, Aris
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