Juki HZL F400 bobbin hook not spinning

[Seamyher89]

Please assist. My bobbin hook is not spinning at some points. I will move it around and sometimes it will spin and others it won't. I'm hoping there's just something stuck down there.

https://www.reddit.com/u/verniyah/s/4jdO9hBg9K

[Seamyher89]

The gear in the back is also clicking and jumping at certain points, as you can see in the video when I am hand cranking the machine. The hook also spins at certain points. It makes me wonder if there is just a jam somewhere, if the gear was absolutely done then the hook wouldn't spin at all, right?

https://www.reddit.com/u/verniyah/s/xqP3ehouwk

[CowboyBob]

@Seamyher89 Take the bobbincase out & unjam the hook. Then take the cover off under the arm,I think you jammed it & stripped the plastic gear that drives the hook.

Edited December 8, 2023 by CowboyBob

[Seamyher89]

Also the machine is bought used so I could not say what cause this problem. 

Edited December 8, 2023 by Seamyher89

[Seamyher89]

@CowboyBob Yes, I did take the case out so now it's just taking the cover off under the arm and checking that out? Should I see if anything got stuck under the bottom? I bought this machine used so I have no idea what the other person did to damage it, kind of lost on this but will definitely try your suggestion 

[CowboyBob]

2 minutes ago, Seamyher89 said:

@CowboyBob Yes, I did take the case out so now it's just taking the cover off under the arm and checking that out? Should I see if anything got stuck under the bottom? I bought this machine used so I have no idea what the other person did to damage it, kind of lost on this but will definitely try your suggestion 

Yes,there could be thread in the groove of the bobbincase that rides in the hook.You'll see the larger black gear that might have bad teeth.

[Seamyher89]

@CowboyBob Wowwww I may have found the issue. Check it out at the link. Is this a gear? Does it just need replacing? I wonder if I could just take the one off of my Singer Heavy Duty

https://www.reddit.com/u/verniyah/s/wJtU4MAflA

[Seamyher89]

I bought the machine used so attempting to fix it. JUKI HZL F400

https://www.reddit.com/u/verniyah/s/HgS1CBuG6r

[Northmount]

3 hours ago, Seamyher89 said:

I bought the machine used so attempting to fix it. JUKI HZL F400

https://www.reddit.com/u/verniyah/s/HgS1CBuG6r

@Seamyher89 Please keep these related posts in one thread instead of starting a new thread each time you find something related to your machine's problem.  I have merged your 2 other threads into this thread.

[CowboyBob]

21 hours ago, Seamyher89 said:

@CowboyBob Wowwww I may have found the issue. Check it out at the link. Is this a gear? Does it just need replacing? I wonder if I could just take the one off of my Singer Heavy Duty

https://www.reddit.com/u/verniyah/s/wJtU4MAflA

I don't the your pics on the link you posted,try posting them here.

[Seamyher89]

@CowboyBob I posted them here! Let me know what you think. I had to take a part a few layers just to finally get access (nothing electrical). I have faith that the reference parts diagram will assist me to put them back together, also I took a bunch of process photos. JUKI HZL F400

Edited December 10, 2023 by Seamyher89

[CowboyBob]

@Seamyher89 There's the problem!! I can check with Juki tomorrow & let you know if they have them.

[Seamyher89]

@CowboyBob thank you !!!