I had an empty zippo, and didn't have any lighter fluid. I know how to fill a lighter, but i've never done it before. Today, i found charcoal fluid in my garage, and decided to use it. ...It didn't work. I was wondering that after i buy some zippo fluid, can i put it in the lighter without worrying about the fact that there's already charcoal fluid in the lighter. If i should be worried, what do i do about it??