We found a 319W with cabinet. The motor is fine. Cleaned it up a lot and oiled all the oil holes but it seems to be continuing to not be able to turn the needle mechanism. I can turn the wheel around to make the needle go up and down but it feels tight. And it doesn't seem as though there's anyway to get inside the machine to clean the internal mechanism. I don't have the manual. I have other old singers that were very gunked up that I completely dismantled and cleaned all the gunk out and oiled and they run like jet engines but this one has a design that prevents one from accessing the internal mechanism. Any suggestions?