ORIGINAL: Ernie Misner
If your spad is rather stiff you might be getting some tank foaming..... so point her up and look for that while on the ground. Make darn sure the pressure nipple is not plugged with a booger. Also, run it up to midrange on the ground and pinch the fuel line. It should speed up slightly, if not, it is running lean in the midrange for some reason still. Check everything for a possible air leak too.
Keep us posted, interesting, hope you don't have one of those GMS, 99 page threads.....
Ernie
Ernie knows of what he speaks.
If all else fails, a spritz or two of Armor All spray on treatment liquid into a gallon of model fuel will tame the beast enough to usually fly without much of a problem. The downside of using this technique is that it does cut the life of the glow plug by about one half, so don't be using expensive glow plugs. Besides, house brand plugs have been working flawlessly in my models for years. A friend and I were the first in our area to fly 3D and that was with cheap plugs. That was back in 84 or so.
Ed Cregger