I recently purchased a Singer 251-12 industrial sewing machine that up until a few days ago worked great. My husband oiled it etc and now it wont pick up and sew stitches at all. I dont know if it is threaded right now or there is maybe a problem with the bobbin or possibly the foot. I do not ave any info on threading this machine and wonder if anyone out there can help with making sure I have it threaded right or that my foot isnt too high.....I dont know what he might have done to it but he did adjust the teeth under the foot....now no sewing!!

thanks sharon