Troubleshooting carb problems while flying gives me the shivers, although I realize there's no more accurate way to do it. Larry Flesner once cleaned up the wreckage of a KR2 that the pilot stalled and spun in off the end of his runway after several flights of trying to iron out a carb problem. I suspect that this kind of "fine-tuning" is best done (if you absolutely have to) with no ram air from outside, in relatively cool air, and with carb heat available. Before a "first flight", I'd make absolutely sure the carb is set up per the manufacturer's recommendations, and lean and rich behavior identified by a mixture meter (best) or EGT readings. Make sure it will richen at least enough to drop the max RPM by 50 RPM at full rich (that's how Ellison has you set it up) while at full throttle operation.
As for the POSa, my advice would be to be very careful flying one that hasn't already been successfully flown on the same engine. I've flown behind one that was supposedly set up perfectly, but the experience was scary. At any given throttle setting it had two completely different locations where it ran OK. Everywhere else it was so lean or rich it threatened to quit. Throttle changes were an adventure, and full throttle was not a happy place at any mixture setting. Don't ever leave the ground like this! "It's all in the needle", they say, but the needle isn't likely to come out of the box "perfect" for your engine, and it's pretty risky flying until you get it dialed in. Good luck... Mark Langford ML at N56ML.com website at http://www.N56ML.com --------------------------------------------------------
