I would like step by step instructions on threading my Brother LX3125 sewing machine.. Thank you.

Your machine is probably out of adjustment. You can probably take it in for service, however, the repair cost may be as much as a new machine.

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increase top thread tension a little, make sure that the top thread is between tension discs.

http://www.sewingpartsonline.com/lookup.html?keywords=Brother+LX3125+Sewing+Machine

try removing needle thread completely and re threading the machine with pressure foot down. as sounds like top tension not working or simply too loose

the best thing to do is have the machine checked at a sewing machine shop

Make sure the thread on the bobbin is wound correctly. If it is incorrectly wound then it will cause the thread to break as well.

did u jam your thread in your bottom bobber you could have thread jamed..

keep a thread tail of 3-5 inches & when you sew make sure the thread is pulled behind the needle each time you sew, even if you have to hold the thread tail with your fingers

Call Brother at 1-877-276-8437 and see if they have something. Or you can look at www.sewingmanualsonline.com and look at the Mademoiselle 1243 model instruction book,, they have a download for that at $10. The picture may let you know if it would work. Good luck

please follow the instruction
1. raise needle to its hieghest position
2. remove hand hole cover plate
3. remove bobbin case from shuttle, pull open latch of bobbin case
4. pull bobbin case straight out of shuttle
5 insert bobbin into bobbin case making sure thread is coming from bobbin.
6. pull thread through slot
7. pull thread under tension spring
8. holding latch open position case into shuttle, and release latch. case should lock into place when latch is released

happy sewing.
regards please rated me.. thanks