Singer 111w155 assistance

[RustyShakleford]

Hi everyone, let me start by saying how immensely helpful this forum has been. 
 

I have an opportunity to purchase a mid 70s singer 111w155. I mostly make small leather goods, the majority being belts (usually 9-10oz with a 2-3oz liner). From what I can gather, this machine should suit my needs. 
 

The seller states that it has a new servo motor, NO speed reducer, and does have a random jam issue. I was told they took it to a repair shop and was told it may be an issue with the clutch. The asking price is 375 negotiable. 
 

My question to the experts here is, 1) is this a fair price for this machine in its current condition, if not what is; and 2) is the jamming issue something that may be common on these machines that I could reasonably figure out and fix myself, or am I better off passing on this one? 

I have no experience with sewing machines, but I am fairly mechanically inclined; spent my teens rebuilding and swapping out muscle car engines and still do my own work on guitars, amps, and guns. 
 

Thanks for any guidance y’all are able to offer. 

[Wyowally]

If it has a servo it doesn't have a clutch. "Jam issue" needs more explanation. Jamming usually means thread jamming. That can be for a number of reasons, most of them only requiring adjustment. I would confirm the mid-70's date if possible. Value depends on real condition and your wants. If it were me I'd throw $300 at him.

[RustyShakleford]

Yeah I believe the seller meant safety clutch, not clutch motor as it does have a servo. She explained it as a thread jam in the bobbin area. Said that it was fixed twice, but didn’t stay fixed for long, and just seemed to happen randomly. Anyway, I met up with her to demonstrate it and she said that she hadn’t used it since it was supposedly fixed a third time. Worked ok. I offered 250 and they agreed to it so I took it home. We will see how it goes. 

Edited October 15, 2021 by RustyShakleford

[huckleberrymoonshine]

My machine (a Singer 111w155 with a servo) had a jamming issue at first, and it was because a thread from the needle (the tail) had wound itself around the bobbin case.  Once the thread was removed, the problem was solved.  I start with long tails of thread and ensure they are held away from the sewing area when I start sewing.  I haven't had the problem since.  I hope your issue will be a minor one, too.  

[Wizcrafts]

There is a difference between machine error and operator error. If a machine has been adjusted and readjusted and a thread jamming situation persists, it may not be the machine itself that's at fault. Most top loading (vertical hook) industrial sewing machines are subject to jamming the top thread around the bobbin basket unless you hold back the starting threads for a couple of stitches. It is what it is. Hold back the top and bottom thread for a few stitches and the jamming will probable go away. If you can't grab the bottom thread, at least hold the top thread back and to the right. If the knot is visible on top from a top tension imbalance, pull down on the bottom thread when you are done sewing, before trimming the thread. You will be able to hide the knots after a few tries.

Note that this thread jamming can also happen on horizontal hook machines. I have to hold back the starting threads on a Consew 206RBL-18 or I get a jam. It is what it is.