I have a Kenmore Model No. 385.16524000. I purchased this machine around 8 or 9 years ago. The feed dogs were fine up and until this morning. I've been sewing on this machine for several years, and all of a sudden the feed dogs are too low. I did not attempt to lower them. I was just sewing. Took a break, came back, and the fabric wouldn't feed through the machine. I've tried raising them according to my instruction's manual to no avail. My husband doesn't know anything about working on sewing machines, but he opened it up and took a look. He is attempting to adjust the height of my feed dogs. The feed dogs are too low. He believes that he has found an adjustment screw and nut. He thinks he may need a special "Phillips Head like" tool of the proper size and a tool to adjust small nuts in tight places. A) Do you think my husband is going in the right direction? B) If so, where can he get proper tools for working on sewing machines?Do you have any idea what could have happened to have caused this and what we can do to fix it?