Gas Vent Problem

Hey I've got a 73 Cj5. There is a hose (believe it's a vent hose) coming out of the top of the gas tank. Whenever I put over a certain amount of gas in the hose starts leaking gas. It stops if you put it at an angle upwards. Anyone know what could be causing this, or how I could fix it. Thanks!

 

POst some pics to get this thread going

 

There should be a filler hose and a smaller vent hose, about 3/4" ID. The vent hose screws into a bulkhead fitting that goes through the side of the larger fill hose. You can replace the hoses, but if you don't have the bulkhead fitting, you'll either have to make it or get one from an intermediate CJ wreck.

 

I'm having a similar problem, when I fill it, it leaks (and gas is too expensive to have it hit the ground!)
I will be dropping the tank, (might as well, it's not quite running yet) and double checking the hoses and the gasket for the fuel gauge sending unit. I figure on something this old, if it still has original fuel lines, it's time to replace them.
<edit> I should say, if it has original rubber fuel lines... the steel ones should be OK.