New gas tank question

I just put a new tank and fuel lines on my Valiant. I figured it would take a few cranks till the gas made its way to the carb. I got it started, but it will only run for a few seconds. A freind of mine said maybe there's air in the line since it's all new line and such. I had a dirt and rust problem with my other tank. So I replaced everything. It is a four tube vent tank. I blocked off the two smaller 1/4 inch vents and used the two 3/8 vent tubes. Do I need to use all four lines? :scratch:

Thanks in advance for your help!!!!!!!!!!!!!!!!!