Originally Posted by IIonPilgrimg
I will also follow this thread with great interest.
On my dory, I have a fuel filter w/ two inputs and dual ballcock valves. I monitor and manually switch between the two tanks. The simplicity of this dual tank design is ingenious, having no moving parts. The only precaution is the main tank must remain tightly sealed for the system to function correctly. To remove the AUX, just swap the position of one vent hose and quick-disconnect the aux fuel line.
good point, i never thought about a leak developing in the seal on the filler cap of the main that would prevent the vacuum needed to pull from the aux. one of the advantages i have on my pwc, is it is also a gravity siphon, as the bottom of the Aux is about 4 inches higher than the top of the main. but i think like mentioned above by CGR, having a hand pump bulb that i can drop inline with the quick connects is a good plan regardless.