I am with John. Baseline pure factory setup FIRST. Make sure you roll back any carb changes done by the PO or you will chase your tail. Agreed, sounds like simple rich condition, idle circuit.
Are you sure the choke is off? Not intended to make you feel like a dummy... I once disassembled a perfectly good motorcycle only to discover it was out of gas. Overthinking... yeah, been there, done that.
Heb Dduw, heb ddim; Duw a digon
I'm that gun-totin', farm-raised, evangelical, pro-environment, OHV ridin'/drivin', Southern civil rights pro-labor Liberal yo' momma told you couldn't possibly exist.