When I have the hood off it runs great, Idles great, good acceleration, steady under load, in test tank. high and low speed carb adjustments very responsive. When I put the hood on it it starts loading up at idle, and gets really rich at higher speeds. I can get it to lean out with the hood on and adjusting the high speed mixture but only if the screw is nearly shut. Then when I pull the hood back off it goes to extreme lean condition and dies. I have to quickly open high and low speed screws a bunch to keep it going. Put the hood back on and it gets really rich again, not just a little bit but close to flooding. It has great and steady spark. I have cleaned the carb, twice, inspected the air intake port in the bottom cowl and it is not obstructed or nothing mis-aligned, I compared the air intake to other known good running engines I have of the same design.
What might be the problem? I suspect I am missing something simple but have no clue what it might be.
What might be the problem? I suspect I am missing something simple but have no clue what it might be.
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