While there are many parts that will be similar or the same between several of the class 15 machines. Yours is different in many respects from the manual for your machine and the one 1.41 referred to.
A manual for your machine would be found at
https://www.sil.si.edu/DigitalCollec...0203/index.htm I'm not sure where I found it, but I have a diagram that shows the needle threading directions for multiple machines. It indicates that the
15-86 (which is what you have) threads from left to right, as does the Smithsonian manual. It also shows the rectangular thread stitch regulator. The one that 1.41 referred to has the round plate stitch regulator and has reverse, which according to the needlebar site, yours does not have. The manual that 1.41 referred to also threads the other direction. Also the bobbin case's finger is going the opposite direction.
Yes, please rewire.
I'm fairly certain that your tension assembly is probably complete. It is like the one in the Smithsonian manual. Many of the older tension assemblies did not have numbers on them.
Janey - Neat people never make the exciting discoveries I do.
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