My experience with most of my RDs has been that it is easy to try and run them too rich at first. Are you able to start it regularly and just have running issues, or is it hard to start?
Assuming that your ignition is 100% solid, giving a good spark and the points are set to break 180 degrees apart, move on to fuel.
I have had to go to just under 1/2 turn out on the HS in some cases. The fuel passages in these carbs are huge. If your carb is clean, the bowl vent is working well, and the float does float, you should get it to start.
If the glass fuel filter bowl is staying full, you can probably assume that your tank is supplying fuel properly.
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