I have a old Kenmore, too. There is no button or lever to lower the feed dogs. They have a plate that you snap on to cover them but when I would FMQ with that plate, it would keep popping off. What a quilting instructor told me to do which helped tremendously was to turn the presser foot to "0" or darn, turn the stitch length to "0" (mine actually is four lines past 24) and use a darning or hopping foot. I could actually FMQ fine with these settings. Good luck!