MY machine has never worked perfet liked I hoped it would. When I embroider the top thread ends up all lose and

Suspect uneven feed of top thread.

Manual for reference if needed.
https://www.brother-usa.com/-/media/brother/product-catalog-media/documents/2018/04/20/08/38/um_pc_8500_en_194.ashx


Please check the following;

• This machine has a horizontal spool. Try using a spool cap that is slightly larger than the spool. Verify spool is in proper orientation, and threaded per instruction. See page 19.
• Embroider foot "Q" is installed per manual instructions. See page 32-33.
• Feed dogs are down (supposed to happen when automatically table is installed but check and make sure).

There should be no looping of thread on bottom side. This would indicate top thread tension is too loose or uneven feed (spool cap and/or orientation). Suggest you preset tension prior to installing table using normal presser foot and single layer of same fabric and same thread. Select a straight short stitch (machine default) and tension 4. With a single layer of fabric, tension at 4 is likely high and you will see bottom thread loop on top side so slowly reduce tension until bottom thread no longer shows on top, Then switch to embroider setup and test run.

Comment below with results and I'll assist further if need be.

http://se.bernina.com/download-n40-sD.html

hers the dl link ok butthey dont make it for win98 just vista and xp ok thx nick

it's sounds like there is something wrong with the motherboard and it would be a good idea to have the sewing machine checked.

Most machines have a stitch counter, stitch forward and step back features. Check your manual and embroidery machine's screens for this.

IN case you have misplaced your manual I found this one for you. It's big so allow time to download.
http://www.itsastitchonline.com/mastery_on_the_web/Mastery_170_180_1-10-02.pdf

have you tried changing the needle
rethread the machine top & bobbin
when embroidering make sure it good quality thread
clean under the needle plate & in the bobbin area for loose threads & lint
make sure the thread your using it not knotty
make sure the tension is set for the thread & needle & fabric your using
make sure the thread has not come off the thread take up lever

try decreasing the tension to 3, if that doesn't help I would suggest to have it checked if it's still under warrenty
also is the fabric & needle & thread compatable?

First check threading. If it is done properly, then it's probably because it is dirty between the lower tension blade and the bobbin case body. Remove this blade, clean, reassemble and it shoud work.

One of the things they don't really tell you about embroidering with the singer machines is that you really do need to use the same color in both the bobbin and the top. No matter how much you adjust the tension, you will still end up with some of the thread from both showing through on the other side, unlike with most other machines.

I found this out from a Singer technician about 3 years ago when I had the same problem with my CE 150 and was going nuts! He worked with both Singers, Vikings and Huskvarna's. and saved my sanity after demonstrating a lot of technical stuff that basically showed me why Singers did this.

Save your sanity-just bite the bullet and use the same thread in the bobbin as you do in the top.

brothers frame is much smaller I think 4 x 4. I have futura 200. found this to happen at first but now now. Make sure when threading that you floss the thread through the top part, it has plastic over it. The thread must fit properly in this part. (flossing means to run back and forth a couple of times holding thread tightly). Also, hold the 2 thread ends when you first start to embroider. Hope this helps

Sounds like the bobbin tension is loose. Look at this website on their "repair" page where it explains how to adjust the bottom(bobbin) tension.
www.sewusa.com