I have a Singer 301 that I use. I'm pretty new too, but decent at using google to search for my answers. I found a PDF manual online for MY machine. Hopefully it helps you out, at least a little bit, on what your problem is. If this PDF doesn't load to the correct page, it's 12/13 in the manual, but 15(ish) according to the PDF.
Hope this helps (lots of pictures in the manual):
http://static.onecreativeblog.com/fi...301-manual.pdf