Closer inspection revealed that the Cotter Pin sheared and the Nut let go. Looks like the Nut loosened off a bit, then took the threads off, and well, you can see the result.
Needless to say, i've ordered the correct rated/grade Cotter Pins as specified in the TM. Time to put her up on stands again for a bit.
Oh, as for the sputtering... It was the plugged up Sock Filter in the Tank
