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Fuel cell plumbing.

Ghostrider 67

Jack Stand Racer #6..and proud of it!
FBBO Gold Member
Local time
9:12 AM
Oct 16, 2014
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Salisbury, Vermont
Need some help with my fuel cell please. Someone tell me where these lines run to. This cell has a feed (got that one lol) , a return and a roll over valve vent. So, where does the return line run to? Where does the roll over valve run to. Or what do they connect to if anything? Thanks. Ghost.

The rollover port should have a ball check inside, can you poke a wire thru all/any of the connections? By "feed" are you referring to the outlet or the fill opening? Can't the builder ID the ports? Strange that a cell would have a top located fuel outlet.
Mike, the cell has two fuel neck fill inlets. One fuel line out to carb One roll over valve with checkball and one return/vent line. Does the rollover valve get capped? Where does the vent line/return line go to? To the front? To each filler cap at the fill end as a vent on both caps?
I added a second inlet neck to the right side of the tank.
The roll-over check ball port is used to vent the tank. Usually connected to a hard line like aluminum that vents below the trunk pan.
The return is just a port that is used to return fuel to the tank when using a by-pass type fuel regulator. It might be short inside to return the fuel to the top of the tank.
The internal part of the Feed port should run to the lowest point of the tank to Feed the fuel pump (if external pump), or go to the internal fuel pump if it has one.
by-pass type fuel regulator? I have a fuel pressure gauge in line.........no regulator. So then that return goes where then?
Maybe this will help......

I have a Holley dual feed 4 barrel with an inline liquid filled pressure gauge to the fuel pump to the tank. THEN.......I have a pop up filler cap on the top of each quarter. These fillers pass down to each side of the tank into fill necks. THEN I have the return, and the rollover. I understand the roll over vents to the outdoors under the car. Got it. So what do I do with the return line? Fuel returning from where in this system? Only thing I can envision is the small line that connects to a filler neck as an overflow just below the cap. In which case i would need to runa tee and one up to each filler cap.
Use the return as an additional vent by adding a rollover valve or cap it. I’d add a bypass regulator and plumb it back to the return. You’ll get maximum fuel volume at the carb that way.