Probably has more crud in the carb body! You didn't say if you flushed it out, or opened it up to see what might be inside the carb body! If you are using Gas-o-hol, instead of pure, old style gasoline, then you had best do a thoro tear down and cleaning of carb. Also, change to fuel lines that are resisting the new gasoline effects.

Are you using fresh gas?
It sounds like you might have some water/crud possibly sloshing around in the bottom of the tank.

Also check the electric connection to the carb fuel solenoid to make sure it's tight.

It could also be dropping spark.

If all above fails, pop off the valve cover and have a look. Sounds kind of loose rockerish to me...

I have been using 1 oz of Seafoam per gallon of gas. Seems to works very well. People here recommended it.