Engine cranks but does not start?

I do have fire, new plugs, new wires, new rotor, new cap, but it won't start, and I do have gas. I left my car at a friend's house because it was leaking from the gas tank. Apon returning and taking the gas tank I had to replace the hose and when I tried to start the vehicle it acted like it wanted to start but it didn't start and then it went, I had it I went through this no start situation. So, I replaced all the things above and it still turns over. I have spark and all the plugs fuel in the carburetor has a single carburetor injector, but it just won't fire it won't catch. I'm trying to figure out what it could be.