I sort of had the same problem. Mine would bog down badly when drilling and I had to back it out as you describe, but mine also would not idle properly even after trying all the adjustments on the carb screw. I took it in to a Jiffy authorized mechanic toward the end of the season. They called Jiffy HQ, described the problem, and the HQ sent a new coil. By the time I got it back there was no chance to try it out on the ice, but just starting it up, revving and running, it runs way better. We’ll see this season if its fixed or not. Glad it has a 2 year warranty.