Dave H M wrote:
If you are going to set up a gravity feed, why not just install a 12 volt veton fuel valve?
Ditto.. Plus a true story:
Years ago (1976) Went to Disneyland.. Met a group of kids in a van who had problems. they had even gone so far as to replace the fuel pump.
Seems the owner had installed a second gas tank, in the fender, above the main tank, and installed a home made changeover in the "Cockpit" area, consistin of TWO valves and a "T" instead of a 3-way vavle.
When the fender tank finished draining into the main tank the fuel pump sucked air from the fender tank and ... Done.
I closed one valve and off they drove.