Things aren't looking too promising for this old girl. The feed dog stepper motor drive circuit seems to be flaky. Getting to this point though was a bit of a chore. First I was thinking the stepper motor itself was cutting out, so out comes the stepper motor:
Everything appears to be ok, so back together it goes:
And back into the machine it goes. First to show you the tight space the thing fits into:
There are two small retaining clips that must be installed after inserting the stepper into the case. The first one dropped inside the machine but fortunately fell out when I turned the machine upside down. The second clip was halfway on the shaft when it decided to sidestep the screwdriver blade and *ping* it went up into the air. A full second went by before I heard it hit something to my left. It sounded vaguely like it landed in the trash can, which was nearly empty:
I figured this was as good a place as any to start looking (after saying that short prayer when things like this happen). Lo, there it was. Thank you God. See it towards the right side of the can.
Finally the stepper motor is back in:
I then got the brilliant idea (somewhat delayed, as I could have saved myself a couple hours of grief and fiddling had the idea come sooner) that the two stepper motors in the sewing machine have the same connectors, so either motor can run off the other's circuit by just swapping plugs in the base. I did this and the zig zag stepper stopped working but the feed dog stepper started reacting properly. This confirmed that the electronic circuit for the feed dog stepper has some issues going on.
So now this machine will be delegated to the "I'll get to this someday, maybe" pile. On to my Fantasia (next blog entry).