fuel delivery issue

Unfortunately I don't have a fuel pressure gauge to watch when it happens. I may have to install one to verify it. I have checked for restrictions from the tank all the way to the carb and can't find anything that's glaringly obvious. No tight bends on the line and all the hose is relatively new. When I built the engine year before last I put a new pump eccentric in it, a moly coated one. I'd think it's ok but no way to say positively without pulling the pump off and looking inside at it. I just picked up an inspection camera and if I don't find any problem soon will do that.

I bet your right about the tank being vented via the filler tube. Forgot about that but I think I remember seeing a small tube running along side the filler tube.

Thanks for the input Del