The machine I probably should tear completely down is Mr. Rusty. A sad little 99K I got free for nothing because he was rusted tight. By all the debris inside I'll bet he was caught in a flood. When I got him the bobbin was still all threaded up and the needle was still there. All rusted. Using G96 gun cleaning solvent, then Liquid Wrench, and a lot of labor I've freed him up and have most of the bottom parts out for deeper cleaning. For the top and the main shaft I am going to give that a kerosene or diesel flushing in the near future. There is just no way to flush out the rest of the debris and rust without a lot of liquid to do the flushing.
Rusty is another of my junk machines I just can't stand to see go to waste. I was going to part him out but now that I'm getting him freed up, I think I'll make a hand crank machine out of him. That aughta be fun.
Joe