I don't know anything about Janomes americangirl but I would try everything possible before buying a new case. new needle, different thread, cleaning the race well, ask the dealer what they think, it could b a lot of things, the fabric maybe. the tension on the bobbin case should b adjustable. Do u have a manual that tells u anything about adjusting the tension. U can always take the case to a dealer & ask them to put n a machine like yours & try it & see how it does. Maybe someone with the same machine will tell u what they think U should do. *4U

Hello Americangirl, I have the same machine as you, and I have just recently had a question about the tension on mine and that was 5 days a go, whether you can find it or not, I hope you can as I got so many answers from so many helpful people. All of their suggestions are great. See if you can find it, I hope you can.