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I just started my fuel lines and was wondering how many of you are plumbing your aircraft the way that zenith shows it or are using something like a andiar valve. I'm using a corvair which is just gravity feed. I don't know if it's worth the $400 or so dollars and lot of extra work, what do you 'all think?
h I'm building a 3rd edition 750
The plumbing from Zen is barely adequate. Rubber hose is a bad idea unless you run it all exposed. Trust me, in five years when you are drilling out a bunch of rivets to change the fuel line you'll be swearing. I used solid aluminum in the rear fuselage, from the wing root to the forward lower seat bulkhead. Teflon stainless braided lines in the wings and in the cockpit.
Bit of a PITA to bend but I did it easily with some patience. The SS lines I got custom cut at an hydraulic shop, spent maybe 300$ on the SS lines. Not cheap but I'll NEVER have to worry about them for the life of the plane... I went overkill with the Andair fuel valve though, dunno why those are so ridiculously expensive... but I love it!
Here's a photo of the bends required for the fuel line in the rear cockpit. I ran it in the side channel along the back and then down the center console. One on each side... double the fun! :D
i guess i should have been a little more specific i have run braided nylon s/s lines from the tank and am using aluminum in the down struts in the cabin just like mark. i just don't know which way to go, with a valve like paul showed or just tie them together before the gascolator I thank you both for you comments it all helps. From the gascolator and thru the f/w will be be braided line again.
I think the problem is that the rubber lines supplied by zen is,they only last about 5
years, and if you have return lines you would have to open nearly half your wings and half of your cabin to replace them.
Lots of different ways and reasons to do this, but I will say that if you can do it in aluminum or stainless, you won't have to be concerned with running fuel with alcohol as you may with the rubber fuel lines.
I wanted to keep the cockpit area free of fuel lines and electrical, so I ran my electrical and fuel in the channel that runs under the 750. I have soundproofing and carpet in the interior, so I didn't want to to have concealed lines and wires underneath the carpet, so everything runs under in the bottom channel, which is covered, and the easily removed cover is secured with blind nuts.
The fuel lines and electrical initially run thru the center console, then drop down, the electrical returning up inside against the firewall, and the fuel line continuing up against the exterior of the firewall.
It really cleaned up the cockpit, and the electrical was easier to run and label as it was all in one area. The electrical dropped into the channel via the center console, but the fuel and brake line dropped down via the additional center console I fabricated for the fuel selector.
(all of my temporary nuts for R&D are always castle nuts)
Here you can see the plumbing for the fuel and brake lines and parking brake
The center console covering the plumbing
Mark makes a point about perhaps not needing a fuel selector for balancing tanks, etc, which is ok, but the first time you have to set down beside the freeway with a compromised line and tank, you will be glad you have that selector so you can fix the issue and shut off that tank and depart before "authorities" arrive.
At least that's what I've heard……..
Your running under in that channel was a great idea, that puts the lines lower than the gascolator. is that a problem?i to don't know and am asking. i take it that you added a cover to the channel area were your lines ran. did you worry about keeping it water tight? i know it wouldn't hurt the hydraulic and brk lines but the electronics?
by the way i loved the way you use that spectropile mtl it looks great and will do the same Thanks for all the great ideas
I have a gascolator on my firewall, and I have a drain at my lowest points behind my gear where my lines comes down for each tank. I sample both of those also as part of my preflight.
Regarding the channel being watertight, with the cap on the channel it's about as watertight as my wing or under my cowling, though I do not have any connectors or splices in those wire runs, and I'm ok with that.
Really happy with the spectropile for a lot of reasons, and the link below is a thread on it.
Love your center console Walt, not as obnoxious as mine... Running the lines in that channel under the fuse is ingenious, I remember seeing a Viking setup like that!!! Wish I would have thought about that, would have saved me lots of headaches under the panel.
Originally I had shut off valves in the wings right at the tank outlets, reachable through the wing access covers. Unlikely the fuel lines would ever leak, maybe seep at a AN6 fitting at the most. I'm more worried about the junk VDO senders leaking. My console shut off valve won't help me there... :( There is a thousand ways to run the lines. When I did mine I did a photo search on the site images and found lots of ideas from other builders on what I liked and didn't and then figured out what would work in my case.
Overall, I'm happy I went with the center console shut off valve with the tank selection, it works great. Still can't figure out why Andair sells these valves for so much though. Here's how my center console wound up... I still have some room on the bottom horizontal area to add a few switches, but it would be pretty tight. Lots of dual stick parts in that area... :D