Originally Posted by
cashs_mom
What she said ^^^^^^^^^^^^^^^^
I recently cleaned my Bernina 180 before a class and put in a new needle. I did a test sew and kept getting occasional little loops on the back. Rethreaded, took the bobbin out and put it back in. Still had occasional loops. As the machine was sewing fine before the cleaning and new needle, I put another new needle in. Sewed fine. I took the class and had no problems. You just never know.
When I needed to change a needle, as I do from time to time. The new needle I put it gave me a mess, loops, noise, broken thread, you name it. After a few minutes and after checking my bobbin, and how my machine was threaded, I changed the new needle for a second new needle. Worked like a charm. No more issues!