By gum, it’s running!
Thank you all, so, so much for all your kind help and suggestions.
And joesnuffy, thank you especially for the videos – it hadn’t clicked for me when each of those adjustment valves would matter and when they wouldn’t.
Per fleetwin’s suggestion, I set the low one at 1.5 turns, and the motor ran for a few seconds before quitting, on the first pull. Progress! SO much better than before.
And then, thinking about Joe’s videos and need2fish’s comment about the missing butterfly on the throttle arm, it dawned on me that when I put the throttle cam back on after replacing the leaf valves this last time around, maybe I didn’t get it snugged up enough and it’d shifted.
Sure enough, when I set the throttle at the notch on the cowling (which I learned about from another super-helpful thread here), there was a great big (well, visible anyway) gap between the cam and the cam follower shaft. They didn’t even begin to touch until the throttle lever was just behind where I was setting it to “start” the thing.
I adjusted the cam forward to where it was supposed to be, snugged up the bolts, left the low-speed valve just as it was before, and on the next pull the little motor started right up and kept right on running.
So it turns out at least one of the problems here was the person wielding the wrench and her imperfect understanding of how that little arm was supposed to work.
Again, thank you all for your guidance and this amazing resource.
Now that I’ve got it running, it throttles up smoothly, and seems to idle okay, but cuts about when the throttle is well ahead of the “slow” mark – is this likely to be a further cam adjustment, or is this where I would (gently, and more patiently than previously) adjust the low-speed needle to get it to idle even slower?
