It seems like several Forum regulars have written in the last 6 months about their experiences with crankshafts actually breaking while at a machine shop or being found to be cracked before or after remachining. Mike (46yblock) and Oldmics have been the most recent, and there was a third posting not too long ago from someone in (?) New Hampshire, I think.



Someone wrote recently about the value of taking a CLOSE look at cranks that have had the radiator cooling fan mounted on their front snout as apparently was the case on some large truck applications.



How wide spread IS this fatigue problem? Is it more common with 312 or 272/292 cranks? Is there a common breaking point, like a particular crank throw?



Is there value to having a used, 50+ year old crank 'destressed' by shot peening or a heat treat process like normalizing?



Input appreciated. -I HATE doing things twice and don't like thinking about the potential collateral damage and cost of having a crank break in the fresh build I'm embarking upon.



Regards,

NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York