Pfaff Coverlock 3.0 serger: in changing needles to positions A and B.....B needle won't tighten enough to hold needle in place. What might I be doing wrong or not doing?

SOURCE: Pfaff serger stuck

your needle bar has been pushed up and is out of adjustment. You need to take off the side cover, there should be a screw on the back of your machine holding it on. Remove this screw, and remove the cover.You may have to remove the light assembly to reach the screw on the needle bar. Once you can see the needle bar, rotate the handwheel until you can see the screw on the needle bar. Loosen this screw SLIGHTLY until you can turn the needle bar. Hold and rotate the needle bar back and forth as you push down slightly. This will lower the bar.Lower it about 1/4 inch. Adjust the needles by turning the bar so that they are straight across. Tighten the needle bar screw so that the bar doesn't move. Turn the handwheel to see if the threads will be picked up. If not, adjust until they are. Tighten the needle bar screw tightly,reinstall the side cover ,and tighten the screw. Change your needles.Rethead and sew.
sewman7

Hassy

• 1388 Answers
• Posted on Nov 15, 2008

SOURCE: serger 794 from pfaff--calanda type 794

There are two holes running vertically inside the needle arm.........the needles are held firm by very small screws or hex allen keys.........they may have worked loose over time, if they have fallen out and been lost, it is a call to your  local Pfaff dealer for advice......be sure to quote model number.
Your User manual may have a diagram to assist.

Have you ever changed the needles since buying this machine ??
Needles ought to be changed every 6 - 8 hrs of sewing, and more often with heavy or abrasive fabric.

SOURCE: Needle holder fell off of machine

there should be an allen screw on the back side of the needle bar clamp push it up and on and make sure its as stright as you can get it and tighten down on the allen screw

SOURCE: Serger won't chain off a stitch. Stitches won't chain and hold to fabric. Added new needle, rethreaded whole machine. Stitches won't connect to fabric or make a chain.

is it possible that the needles are in backwards?
it's very possible that the machine is out of time & would have to be taken to a sewing machine repair shop to be retimed

SOURCE: My Singer 5050 sewing machine won't let me

sounds like a part is damaged or jamed, the machine needs to be checked
to see what's wrong with it