Juki 341 issue

[Constabulary]

As I said before - reinstall all parts and make sure the small tab of the bobbin case is inside the notch (not left or right of it) and then check again because thats how we can se if something is binding under regular sewing conditions.

[Darren Brosowski]

My first suggestion was going to be the basket as it only takes a microscopic amount of thread or rubbish to cause binding.

Pull it back out and look very closely at the male and female slots to see if something is in there. If it is damaged in any way I would replace rather than try to polish out

[the deacon]

reinstalled and there is no more binding. I have no idea why it is working now. Perhaps I didn't notice if the bobbin case was not inside the notch when I first took it apart. One question. I notice that my bobbin opening lever has an ever so slight bit of play and a distinct clicking sound when wobbled. Should that be?

 

thanks for all the help!

Edited January 10, 2018 by the deacon

[the deacon]

scratch that. After test sewing it's still happening, though intermittently. Ahh the joys of machine maintenance.

 

[brmax]

What is the noticeable difference when oil is applied to the basket, in typical amount. I am curious if some grit has made a bur in the raceway. Best to have the throat plate back on while checking this. 

Good day

Floyd

[the deacon]

I applied some oil when I re installed the basket. This may have accounted for the machine to be working a bit better than before. I did run my thumb nail around the chase and basket. I didn't feel any burrs. I suppose I could order a new one and see if that solves the problem.

I've never adjusted/set the timing on the machine. I'm wondering if that could be the issue?

[Uwe]

This binding trouble may have to do with the bobbin case opener in two totally different ways.

1. When the throat plate is removed like in your first video, the bobbin case rotates more than it normally does and the bobbin case opener finger pushes against the triangular bobbin case tab and causes a bind. You can see the bobbin case popping backwards when the bind releases.

2. When the throat plate is installed, your bobbin case may simply be pulled back too much, causing the tab inside the throat plate cutout to touch and cause a bind. Neither of the videos shows that detail to verify or disprove.

I made a video that hopefully will illustrate what I was trying to say in words above:

 

Edited January 13, 2018 by Uwe

[Constabulary]

Not possible to explain this any better - again great video , Uwe  

This works for any sewing machine rotating hook who have a bobbin case opener similar to the one shown in the video not just Juki 341 (Pfaff, Singer, Consew, Seiko, Adler... you name it) so it´s worth watching.

 

[the deacon]

Uwe,

Exceptionally helpful video, Danke Uwe. The bobbin case timing was off. I have adjusted and have much better results. I noticed on your video the loop that is created by the hook is much tighter than mine which seems to me would cause less efficient stitch execution and/or sloppier stitches (first video). Is there an adjustment to make to tighten that up. Also I noticed there is a little bit of play with the finger that pulls back the bobbin switch, there is also an audible click when moved (second video). Is that normal or is this part loose in some way.

Again, thanks so much for a great video tutorial.

Dieter

 

[Wizcrafts]

You can loosen and tighten up the loop by readjusting the position of the check spring disks. Loosen the small screw near the top of the disks, which sits inside a curved slot. Use your fingers to turn the disks one way or the other until you get the amount of slack you are happy with. Then tighten down the set screw.