Copperized steel tube OK for fuel lines?

[iTurbo]

I'm going to try and make new fuel hard lines for a Spirit R/T today. 6-7 years ago, I had removed the original fuel lines and replaced them with 3/8" aluminum tube from Summit. They only lasted about 5 years before galvanic corrosion took over and the aluminum developed pitting where the line clamps secured them to the underside of the car. It got bad enough that it eventually started to spray fuel!

A few weeks back I had asked about PTFE hose, which is braided stainless hose with a Teflon inner liner. Ultimately what I would really like to do though, is use steel hard line. I want to stay away from using anything that comes packaged in a large coil, and start with rigid tube instead. My thought is that the final product and bends will look nicer if I start with straight sections of tube.

I went to NAPA and found 3/8" straight steel tube that comes in a variety of lengths up to 60". It is for brake lines and comes double flared with nuts already on them. I figured I would just cut off the double flare and reflare the ends for 37' -6AN flare. It is copperized steel, so the inside is copper coated and the outside is mild steel. They also have the same line available with a PVF (poly vinyl flouride) outer coating for ultimate corrosion resisitance. Would this stuff be OK for fuel line use?

I had also looked into copper/nickel (Cunifer) lines, but they only come packaged in coils and I'm looking to avoid having wavy looking hard lines.

[iangoround]

Yes, that is fine for fuel use. In fact, it is how I built the fuel system for my car. I used two or three 60" sections. I cut the flare off one end of the 1st chunk and reflared with a nut for an AN fitting, ran it down from the engine bay in the stock location, joined with a union to a second section back to the fuel filter, and from there to the fuel tank.

[iTurbo]

Great, thanks for the input.

I'm in the process of bending up the lines now. I'm doing both supply and return with it. Like you, I also plan to cut the double flare/nut off the ends near the tank and underhood and put a 6AN flare on with the proper AN tube sleeve and nut. I'm going to leave the double flare/nut on between the sections and join them with a union for simplicities sake.

[iTurbo]

Well today was a total *fail* as far as bending the new fuel lines up. I was dreading having to do this, and sure enough I ended up trashing both new 60" line sections I bought. It wasn't pretty but I guess it just going to take some practice.

I think I'm going to try again with a slightly different strategy. Next time I'm going to get shorter sections of the same kind of line, which will automatically make it easier to bend into place along the firewall and inner fender. It should also help place the location of the unions needed to join the sections in a much more accessible place under the vehicle. I'm thinking of something like using a 30" section from the inner fender to the bottom of the car, a 60" section along the bottom of car, then a 24" or so from where the original fuel filter was to the tank. I'm 'bent' on getting this right.

[iTurbo]

Things are going much better now. I used 30" lines for the inner fender/firewall section. Basically it starts adjacent to the strut tower (like stock) and goes down to the bottom of the car where it starts to go parallel with the ground. I even reused the OEM line bracket on the lower firewall but had to ream out the rubber bushings to make room for the larger 3/8" lines. Tomorrow I plan to use 60" line sections to do the the run along the bottom of the car which should be easy.

[Turbo Joe]

the nickle/copper lines ( Ni-Co) are actually really nice to work with ! there just a little tuffer to bend than aluminium line compaired. Also thats what I had just used on my car when i removed all the braided fuel line. I even did all my brake lines with this stuff, so i shouldn't have to touch any lines in this car again and having solid lines with no joints is nice insurance against leaks. just a FYI on how that Ni-co stuff is to work with.

[iTurbo]

Yeah, I noticed NAPA sells the Copper/Nickel line too nowadays. I guess what turned me off is the fact that it only seems to be available in coils (no rigid straight sections). When I had previously used aluminum line for this car, I bought the aluminum line from Summit which also came in a coil. It was easy to bend and flare for sure! But one thing I didn't like is that even the straight sections of the line weren't exactly *straight*, and I was never really happy with the final outcome. I mean, who wouldn't love to post pictures of beautifully bent bent fuel or brake lines on the forum or show of at SDAC?! Because everybody really wants to see under hood and the 'bar' has been raised up quite a bit as evidenced by a lot of the Project forum threads.

The Co/Ni line seems to be best as far as materials and easy of installation though, particularly corrosion resistance. It's just that I'm really wanting nice appearing lines and I'm not sure if my own ability would enable the Co/Ni lines to make me happy. I don't know if it's the perfectionist in me, or that I'm demanding too much symmetry or what. If the rigid copperized steel tube from NAPA doesn't work, I will be looking at Cunifer next though. I had considered PTFE braided hose, but I don't think the limited bend radius would work for me.

I am learning a lot about bending and making fuel lines though, even if today was a crash course. 10 years ago I had used the same copperized steel tube to remake all the brake lines on my Shelby Lancer (in 3/16" of course) and it has been great ever since.

[iTurbo]

I found a different product at NAPA today. According to their catalog, it is also copperized steel tube, but has a PVF (poly vinyl fluorine) coating. It is available in straight sections with double flare on both ends, BUT, it is much easier to bend than the normal copperized steel tube I have been using. With the PVF coating it is also more corrosion resisitant.

As far as I can tell, it's NAPA's in house version of Poly Armour. I ordered two 60" and two 40" sections. I have a friend that works at NAPA (who is buying the car) and he demonstrated how easy it was to bend and I was pretty amazed compared to the regular copperized tubing.

Poly Armour from AGS:
http://www.agscompany.com/faq/10

NAPA product:
http://www.napaonline.com/Catalog/Ca...479_0361071985

[Dez]

Very nice! I bookmarked the NAPA page for future reference, as I am sure this will come in handy soon enough. Hope to see some pics of the finished product.

Thank you and good luck!