Small Engines (Lawn Mowers, etc.): extra gas tank, gal gas tank, fuel line

Question
I have a generator with a 1 gal. gas tank. I added another gal. gas tank to it so i could go longer between fill up but it doesn't work. Do i need to add fuel line shut-off to each line going to the engine instead of using a "y" that i have now? Thanks

Answer
Without seeing what you did exactly its hard to offer advice.  Is the tank you added higher?  Is it flowing before you hook it into your Y?  It should work just find unless you dont have enough height.  It will need to be a slight bit higher the your original tank.  

And make sure the cap is vented or you will have a vacuum inside that will not allow the fuel to come out of the tank either.