cjr,
I suspect this machine had been sitting for quite a while before I got it. I've oiled and greased it as well as cleaned it. I just finished putting together a strip of 36 3 1/2" squares for a quilt I'm starting and as I used it it seemed to begin to ease up. I also adjusted the top tension a bit and the thread problems stopped.
It just needs to be used I do think.
Joe