Quote Originally Posted by the evil twin View Post
Petty tanks aren't supposed to have a 'breather' direct to atmosphere
That is the job of the Charcoal Canister.

You should have the fill line breather that goes from your tank to the top of the filler so you don't get blowback when filling.
Both the filler and fill breather should be sealed from atmosphere with the cap on.
The tank 'evaporates' to atmosphere via the Charcoal Canister and not a separate line
Ok cool, thanx mate. I'm pretty confident now, that I can leave the fuel tank system as it is.
Kallen was telling me the same thing, but I was still bit paranoid. ('cos I dismantled every part of the fuel tank system, including the fill point, to clean them).
Cheers.