Thank you!!! I fixed it!!!!
You guys, THANK you more than I can say. I am so happy because even though I realize this was not brain surgery, I was intimidated by it, and I appear to have succeeded!
I watched the video that was recommended, and in the end it was educational but it was really hard to see where I needed to see on my Great Blue Clone. I had a look at it today; and in the end, I did as follows:
See these photos, there is a set screw; it was not very snug (it was also bruised already, on an otherwise near-pristine machine; so I am not the first to dig in there! Very awkward angle, and without the proper screwdriver, easy to bruise the head).
The set screw appears to have to do with keeping the needle bar timing from straying out of time. As it was not too snug, I imagine this is why it went out of time.
So, I loosened the screw and lined the mechanism up such that when the needle was at its lowest, the needle bar and the arm of the mechanism on which the set screw is, were parallel. Crud, that's awkward grammar. I hope it was clear! Shown are two photos, and if I have done this correctly, when the needle is in its lowest position, these are parallel, and as well, when the needle is in its highest, these are again parallel, only by now the mechanism has travelled upwards.
I sewed some glorious stitches, so it works! And no needle hitting where it ought not. But I would love it is someone could confirm whether this parallel rule is a good rule?
The first photo shows the needle-down position; the second show the needle-up position.
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