Posted for "Tommy James" <twjames@healed.org>:

Hi Paul,
To me this would be a question of temperature and pressure.  If the fuel can
cool down in the sump that would be better than running all the way back to
a tank.
What happens, pressure wise, when the 2 gallon sump fills up?  Actually, I
don't think it would be a problem, but an item to consider any way.
The surest way is to run the overflow back to a main tank.  Why did you
choose a 2 gallon sump?
Regards,
Tommy James<><