Just picked up a DS90, Brand new, dealer didn't have time to prep it, so I was doing it myself. Pulled the carb and cleaned it all out, looked like a gel pac may have been in there. Put it back on , runs good, seems to surge after opening the throttle and releasing it back to idle. It surges for a bit, then drop right down and almost stalls, or stall completely. I've played with the air screw, but it seems I can't turn it out more than a 1/4 turn and it kills the motor. Had anyone had a similar problem? It almost seems like the pilot is to lean from the factory?
Thanks for any input?

Crazeejames