Hi Jerry -- initial idle settings shouldn't be much different than Chryslers, where appropriate. From lightly closed, open l.s. needle counterclockwise 1 1/2 to 2. Open the h.s. needle about 1 turn. Assuming the carb is clean, flow from the tank through the valve is good, and pumping water OK, let it warm up a little at idle or fast idle using the initial settings -- wherever it starts and runs. Object is to lean the idle mix as lean as you can with a low idle and no lean sneeze. Typical procedure is to throttle it down as low as it will go, lean the l.s. mix (rpms will increase), then lower the throttle a little more until you hit a low idle, running smoothly. 650 rpms in gear is pretty standard across the board, but I go by sound.
You can run that little unit in a barrel or similar container to get some back pressure. A plastic trash can works well for me with the little ones. The engine will stall at idle if the air/fuel mix is too lean. As you know, it's not the same issue as an overly lean gas and oil ratio. Low and slow is the object, leanest setting to achieve that. The h.s. setting will end up around 3/4 open in my experience. Should be able to throttle up and down without stumbling. You can get it very close running in a barrel with the 2hp, and the kid can tweak it a little when he's got it on the dinghy -- Good kid's motor. Don't forget to open the fuel shutoff.
Stumbling signals too rich. Lean sneeze is too lean. Correct setting is somewhere in the middle between those extremes. There's a couple of stickies around (Joe Reeves and others), but it's standard stuff. Not sure if the single cyl. 2 is much touchier than the small 2 cyl. J. and E.s -- early 3's run like sewing machines.
[ed. good to snug up the jam nuts for him when you have it dialed in. 1/8 turn one way or the other can spoil it, and don't want the needles to rattle loose or have the kid whipping them around.]
