[cheesy]

Almost have the welder dialed back in. New contact tip, nozzle, .030 flux core wire, cleaned internal connection, and reworked the ground clamp. But, I found the real culprit. The wire feed drive roller is shot with a teeny tiny flat spot on it. Even with the clamp bottomed out, once the flat spot meets the idler roller, the wire stops moving until the flat spot is past the idler. Explains a lot.

I have a new roller on order. In the meantime, I flipped the roller to use the .025 side with just enough pressure on the idler roller to move the wire. Works a hell of a lot better.