Brother 884-T78 Operation Manual page 29

Handwheel
Thread is getting tangled.
Doesn't Rotate
Re-thread machine.
Clean bobbin case and under
14-16.25
needle plate. Oil the machine.
Thread Gets
Upper threading is not
threaded correctly.
Tangled on Wrong
Re-thread machine
Side of Fabric
properly.
If you find it difficult to turn the handwheel, you may also see "Sewing Machine Doesn't Run" in "Trouble Shooting".
✽
Needle is not attached Needle is bent, or tip is
correctly. dull.
Change needle.
Reattach.
11
Upper thread tension is
Bobbin case may be scratched.
too low.
Remove needle plate and
Increase tension.
15
17 check bobbin case.
11
27