Interesting that the crack seems to mainly stem from the outboard engine mounting bolt. With twin-rail SB45s I normally expect the crack at the inboard bolt.
We need to get more information on how many cracked single-deckers are around, versus how many cracked twin rails, and whether there are any cracked rails on mowers that came from the factory with set screw engine-side clutch halves, versus the old captive cotter type. At the moment I haven't heard of a crack on a set-screw mower.
