GCV 160 Engine does not start.

Two attempts ago I managed to cut the lawn, but the engine took forever to get started, and ran weakly upon mowing. I read up on the problem (google is filled with problems on the GCV 160), and i, indicated that the spark plug was the problem. I changed this and started the mower in my basement and it ran just fine for 30 seconds or so before I shut it off thinking it was fixed. I go to do the final cut of the season, and low and behold, it its the same problem; starts up after a battle and dies seconds later. This machine was bought this past spring, pretty disappointed.

I have the thing apart and am working on it, but don't really know what direction to go in? Carb, fly wheel? Anyone have any ideas? I'm not a complete newbie to lawn mower repair.

GCV 160 Engine does not start.