Yes, new os 4 stroke. Tried another to, no luck. It will idle rich for maybe a minute or less then sputters and wants to quit, Then I put the hot shot on and tweak a little more . When I get to lean with the low needle it will quit suddenly. Seems to have a very short window, even idling good it will still load up and quit. I tried the tee in the line from pump to carb with no luck. O-ring on the high needle valve looks good and the valves are really clean. Using cahusker's advice got it close, just can't find that sweet spot.