Good. My suspicion is that there is a small piece of debris/rust still in one of the orifices of the carburetor. See if you can get a little piece of floral wire or other very small rod or wire to run through various holes.
Even if you can't see straight through a hole with right angles, you should be able to see light if you put a little flashlight up to one end.
What's the story on the carb? I'm not familiar with Zenith on stovebolts.
Everything I've learned about stovebolt carbs from this site is that the Carter YF is preferred over the Rochester B and that almost no one uses the Carter W-1 or whatever it was called.
Last edited by Otto Skorzeny; 12/07/2022 1:02 AM.