Just rebuilt carb.idle tube goes fromnozzel well to fitting on carb body. fitting on carb body is blocked.I could not get a drill bit thru it(not spinning)is this supposed to be.engine runs good at idle but will not speed up,but I beleive that problem is from a crack in the top carb body cover.Just want to know about the idle tube.should it be drilled out or left as is?Thanks much. dave(I dont understand why there would be a tube to a closed fitting. 