I got the problem figured out!!!
Guess what it was?
The WRONG bobbin was in there.
That's how it came to me. And with no manual, how would I know?
Mystery solved.
I kinda wondered when the bobbin case didn't seem to be fully engaging.
It would snap into place but not a strong snap.
With my Viking, I can only use the Husqvarna bobbins,
but fortunately I still have my old Singer machine.
Found one still all wound up, and it worked!
The machine sews GREAT.
I'm still going to have a friend come over this week & look at it.
I want to make sure that it's as good & clean as it looks,
and maybe it could use a drop or two of oil.
Thanks, everyone! :-)