"The initial setting for your
"The initial setting for your engine is supposed to be 1 7/8 turns. So you are not too far off. The main thing is if you turn it out more, will the cylinder start faultering? If so, note where that is and turn the screw back in until the cylinder improves then faulters again. Then find the midpoint of those two spots. Hit the throttle quickly...if it sneezes then adjust the screw out a little. Turning them out just a little after you hit the sweet spot will probably fix any sneezing. You may have to adjust the other carbs as well.
It would be excellant if you can sync the carbs, especially since you are moving them around. If they are out of sync, you will see a definite improvement in how it runs as you zero the carbs in.
You should again go back to the idle mixture screws to assure they do not need further adjustments.
It is all an iterative process.
If the idle screws are not damaged, worn or corroded, there should not be a need to change them. If a carb is giving me problems, I always change the o rings, especially on the idle jet to remove all doubts. Since the o rings come as a set, change them all.
While doing these adjustments, you should keep the rpm around 950 plus/minus 50. I tend to set the idle closer to 980-990. The idle will increase as you keep making adjustments. Be sure to readjust idle as you go.
When everything is ready to go, be sure to use a good fuel treatment (all the time) such as PRI-G, Sea Foam, etc. There are several out there.
If you do not already have one, adding a water separating fuel filter in the fuel line between the tank and the engine will minimize any water problems that may arise in the future."