Bill Eck wrote:    Snip
<< . I will plumb positive vent to the mains and
 > "static  port"  style pressure to the sump. I hope to avoid the fuel
 > troubles Velocity's have had with only one tank feeding.  Bill Eck STD >>

Careful, Bill,  Too much positive to the mains and a little negative to the
sump can pump fuel overboard unless the negative vent is real high.

Bob Darrah

Scott Gettings wrote:

Why not just have the sump vented by a separate line terminated with a low
pressure one-way valve?  If the high-pressure fuel is returning to the sump, it
should not normally need any venting as long as fuel was flowing from one or both
tanks into the sump.   However, in an unusual situation, the sump tank would have
a separate vent to prevent a vacuum from forming and the separate line would
prevent any fuel from cross-flowing thru the vents.

Scott Gettings

 
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