i have a 240 6cyl with a 1bbl carb. i recently put a carb kit in it. almost every morning, when i start it, it will run long enough to run the gas out of the bowl and quit because my needle valve is hung. i can then go out and tap the top of the carb and you can hear it fall back down and let the gas in. it doesnt do it again untill the next morning. it has good gas pressure....any ideas of how to fix it

 

Does your Needle have a Rubber tip on it?
You might have a snag in the seat, catching the needle tip.
Also you might have a little bit of misalignment in the Float, and it's binding on the side of the Carb or some other obstruction.
Is there a Fine wire spring missing? It's on the Float/needle junction.