How to determine which hose goes to which port when replacing gas tank?

[MThomas]

The gas lines are easy since one goes one direction, the other goes the opposite direction.
However there are two hoses that just slide onto adapters and I forgot to notate which came from which on the gas tank.
Is there any way to determine this? I don't even know what those hoses are :-o

[Sunbeemer]

One is a drain line from the rim around the gas cap and the other is a vapor line from the charcoal canister.
Blow on one of the tubes with the gas cap open and feel for air escaping from the small drain hole in the filler's rim. That tube just drains to the ground.
And if you then seal the gas cap and blow on the other line and feel building back pressure, that confirms that line should be connected to the tube that goes to the carbon canister.

[Buckster]

I have made this mistake as well. Next time you disassemble, leave one barb connector on the tank side line and the other barb connector on the bottom side line.

[MThomas]

One is a drain line from the rim around the gas cap and the other is a vapor line from the charcoal canister.
Blow on one of the tubes with the gas cap open and feel for air escaping from the small drain hole in the filler's rim. That tube just drains to the ground.
And if you then seal the gas cap and blow on the other line and feel building back pressure, that confirms that line should be connected to the tube that goes to the carbon canister.

Thank you, I will try that