Nothing similar enough in the book to give any advice. If I were you, I'd try slightly loosening every screw slightly (from the top L-C-R control all the way to the needle bar) that looked like there's adjustment capability (a slot, possible eccentric, etc)...& try moving the needle bar to center. Then tighten them all. Your adjustment (set screw, eccentric, slot...whatever) is for sure SOMEPLACE between the L-C-R control & the needle bar. Then deal with the bobbin carrier if necessary.