Fuel Filler - Breather
I have a query regarding my fuel tank filler / breather.
Picture one, you can see the breather hose come off the top of the fixed tank.
Picture two, you can see where the breather comes up into the small hole at the top of the filler pipe.
However my question is, whilst this allows the tank to breath when filling, what about when it's running? Picture 3 shows the filler cap, which is nicely sealed with an O-Ring...
From my tote tank days, I know I need to let these tanks breath when they are being used thus maintaining correct pressure as the totes empty.
Is the situation the same with a fixed tank? If so, how do I let it 'breath' when it's being used, as I can't leave the filler cap undone as that'd get pretty wet........