Originally Posted by the casual quilter

If you take out your bobbin case to brush the lint out, you will see a hole with "fuzz" in it. Put a drop of oil on the fuzz. Just a drop. And do NOT try to pick the fuzz out of the hole. It's is really the wick. One more bit of un-asked for advice - don't use too much oil and not too often. Just one small drop every once in a while.