If, when you removed the glowplug and spun the engine, fuel came out, you may have the needles too rich. I had this trouble recently with a new ST G45 engine. The NV settings in the manual were too rich to allow it to be started, even with the electric. It just spewed fuel out the exhaust. I've yet to see a mid-sized supertigre engine that needed the NV open more than 2 turns for a rich setting, so long as it had muffler pressure to the tank. Try at leaner settings.

If you've just "pumped the excess fuel" out of your engine, by removing the glowplug and spinning, try to start the engine WITHOUT connecting the fuel and pressure lines. It should start and run strong for a couple seconds while it burns out the remaining fuel. After that, set the high speed needle to 2 turns, prime only enough to fill the fuel lines, and re-start it.

Bobmac's suggestion to check the gasket under the carb is a good one too...

Good luck,

J