Found a stray bushing in my Seiko CW8-B

[WMages]

I do not have an ftp site to upload images here but the part I found wandering around in my machine is about 1/8" thick 1/4" in diameter and flat on two sides with an unthreaded hole in it. I presume it's a bushing. I can message or email images. 
 

My Seiko CW-8B started leaving the top thread (138) lay on top in tight radius turns. I tried making certain the needle had started back up before turning and didn't resolve the issue. Although there have been zero changes to bobbin tension since it sewed fine, and no major changes to top thread tension and same size needle. 

Yesterday, it was missing occasional stitches even in straight aways on a belt.  

I investigated this morning with an intention of increasing the bobbin tension by a half turn. I paused and took time to do a little cleaning and found this small bushing lying inside the chamber that houses the bobbin case. It's about an eight inch thick and in threaded. It has straight sides so I assume it's a bushing that isn't supposed to rotate. This also indicates to me there is likely a small screw somewhere yet none fell out when I slipped off the lower cup from the end of the cylinder? I'm fairly mechanically inclined but do not have experience with a sewing machine. I'm reluctant t try to remove the bobbin case for fear of getting its out of one. 

I'm looking for advice if anyone recognizes what part this is. I do not have a schematic for this machine.

[fredk]

23 minutes ago, WMages said:

I do not have an ftp site to upload images

You can paste photos directly* from your computer or phone. They need sized to no more than 800 x 600 pixels, ie about 150kb

* this is actually preferred

[Northmount]

44 minutes ago, WMages said:

I do not have an ftp site to upload images

I don't know where you get that idea from!  At the bottom of the comment box it provides some very simple instructions.

As Fredk says, reducing file size is preferred, to 800 pixels in the longest dimension.  Especially helpful to members on the fringes of the internet where large files take forever to download.

[friquant]

2 hours ago, WMages said:

Yesterday, it was missing occasional stitches even in straight aways on a belt.  

I would check if the machine is in time. And if it has a safety clutch, make sure it is engaged.

If you can, make a slow, closeup video like Karbo's here to show the timing of your machine: https://leatherworker.net/forum/topic/131845-pfaff-345-issues/#findComment-784860 and post it for us  to review