Originally Posted by
monopas
If it makes a little slapping sound in the bobbin area when you turn the handwheel by hand, the jib screw might be missing (or put in from the back). Might be a bad idea to try to sew with it if that is the case.
Be careful of missing screws in general, as I think some of them are difficult to find replacements for.
Actually, the majority of the screws are available and work just fine. I sell a lot of them because they get lost when people take the machines apart to clean.