Mordy another interesting point to note on that photo is the heavy burnishing
on part of the mating faces of the 2 broken areas. This happened AFTER the
shaft broke. The faces were at an angle to each other, creating a wedging
action
& resulting in a heavy axial loads, pushing the 2 disconnected sections of
the shaft apart. The burnished witness marks were perfectly aligned with each
other fore & aft with the shaft sections positioned apart from each other, as
would be when the engine was running & power being transmitted. From this the
conclusion could be made that this engine did indeed run for some time with a 2
piece crank, albeit not too long!
BTW ultimate failure occurred when big end started slamming into the block
hard, but was also progressive as evidenced by witness marks.
Glen
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