How familiar are you with that type of carb. Did you put a new noodle gasket and small o ring in. On those that have been set up for a while with the E gas, welch plugs have to come out and be put back in. I had 1 of those give me fits one time.
I have a gallon of dip I use. Then spray with a can of carb cleaner. You can't hurry up on those Nikki's......