Well here goes. I checked the fuel lines and found one that was cracked. Make note to self. When replacing fuel lines, toss the old ones out. I replaced them with some lines I found in my field box. Guess they were used. Anyway, I pulled the engine and replaced the o-ring on the carb and the needle valve. Put it back together and tried it out less than an hour ago. Same damn thing happened. However, it only happens when the engine gets hot. When the engine is cold, it is fine. I am running the correct mixture as per the engine instructions. After it occurs, if I let it set to cool off, it is fine until it heats up again. So what ever is causing it, it is a heat related issue. I did notice in the grand scheme of things, the threads for the glow plug are hosed. Apparently, somewhere along the line, I cross threaded the plug in the engine. Could this be causing the problem?