Should I install Fuel Return Lines

[sglynn]

I'm bulding my 7A wing now. Should I install fuel return lines? I've read the posts. I don't know what engine, or fuel pumps or fuel system I'm going to use yet. I'm always worried about adding un-necessary weight and complexity. So what is the general consensus about having fuel return lines? Your efforts replying are appreciated.

[flyvans.com]

Hi Steve,

we've put one in each tank and ended up using it with the ECI fuel injection system on our Mattituck TMX IO-360.
Didn't decide on an engine until later in the build and wanted to keep all options open. That's also why the return lines are oversize (-6) instead of -4 (ECI) or -5 (when we were looking into the subaru options).
i wouldn't be worried about weight so much. the "biggie" is rather the required duplex fuel selector valve from andair, which is $$$ (but also great quality and the only way to go when using return lines IMHO since it avoids fuel management issues, overflow of a tank etc...)
let me know if you have further questions about the ECI integration. We're not flying yet, so no performance reports yet.
it gets you ready(er) for alternative fuels, should be safer with the use of mogas (vapour lock) as well as you're ready in case diesels ever take off down the road.

kind regards,
bernie

[Dave_Boxall]

Don't proseal the inspection plates on the end of the tanks, then it's easy enough to fit the return line at any point until you put the tanks on the wings and the wings on the aircraft...

Dave

[DaX]

I decided to add AN6 return lines that terminate in the center bay of the tank on my RV-7. I just installed them - check out my log in my signature for details. FYI I am copying Brad Oliver.

[frankh]

And converted them for flop tubes and returns for my custom electric pumps in the wing roots system.

its really not hard to install the reutns later but I would probably put them in before glueing in the inboard rib to avoid filling thank with shavings.

Frank