One more stray thought, and again, forgive me if this was already discussed.
Did you have this carb apart, clean/rebuild? If so, did you do anything with those pesky fiber needle valve seal/stiffeners located deep inside the valve cavity… The carb will suck air around the needle valve if those packing washers are missing/damaged or if the gland nut isn’t tight enough…The gland nut should be snug enough so it takes some effort to turn the needle with the knob installed, you should not be able to turn the needle by hand without the knob installed. I’m not saying pull all those messy fiber washers out of there, it is a messy job that can oftentimes introduce crud (pieces of the washers) into the needle valve and mixing pocket…Just make sure the nut is snug so air won’t leak around the needle into the mixing pocket…This could explain why the needle must be set out at two turns to run…Just a thought….D
