metal fuel lines

[Mr. Lav]

have a quick question on fuel lines. What is everyone running for fuel lines? Getting ready to replace and have seen people running metal looking for the size of line and where to pick up some at. I'm running the mustang EFI, so pressure and return Thanks Alex

[B.O.B.]

I ran 3/8 stainless for both. Got it from Summit. Some say you can run a smaller return but it was just easier for me to run the same.

[Strike2]

I'm running a 96 Explorer EFI/fuel pump and PTFE hose from summit, although running hard lines is much cheaper.

https://www.summitracing.com/parts/sum-220985

[cpldavis37]

I bought mine from BC Bronco's.

[Viperwolf1]

Bought a roll of 3/8" steel tubing from napa.

[Digger]

3/8" steel hardline for pressure side, 5/16" steel hardline for return.

I used poly for the soft lines (https://www.amazon.com/gp/product/B000CIXMM8/ref=oh_aui_search_asin_title?ie=UTF8&psc=1) and SAE J2044 quick disconnects (https://www.amazon.com/gp/product/B000E348A6/ref=oh_aui_search_asin_title?ie=UTF8&psc=1) to make the jump from hardlines to filters, tank and engine.

[Gunnibronco]

3/8" steel hardline for pressure side, 5/16" steel hardline for return.

I used poly for the soft lines (https://www.amazon.com/gp/product/B000CIXMM8/ref=oh_aui_search_asin_title?ie=UTF8&psc=1) and SAE J2044 quick disconnects (https://www.amazon.com/gp/product/B000E348A6/ref=oh_aui_search_asin_title?ie=UTF8&psc=1) to make the jump from hardlines to filters, tank and engine.

To attach the quick connect to the steel line it needs the push connector style flare?

http://www.gtsparkplugs.com/images/Mast ... Tool_4.jpg

And the barbed end just fits inside the nylon line with no other clamp or fitting?

Just want to make sure I understand. I have never loved using the braided fuel hose, and buying the EFI rated stuff gets silly expensive.

[Digger]

3/8" steel hardline for pressure side, 5/16" steel hardline for return.

I used poly for the soft lines (https://www.amazon.com/gp/product/B000CIXMM8/ref=oh_aui_search_asin_title?ie=UTF8&psc=1) and SAE J2044 quick disconnects (https://www.amazon.com/gp/product/B000E348A6/ref=oh_aui_search_asin_title?ie=UTF8&psc=1) to make the jump from hardlines to filters, tank and engine.

To attach the quick connect to the steel line it needs the push connector style flare?

http://www.gtsparkplugs.com/images/Mast ... Tool_4.jpg

And the barbed end just fits inside the nylon line with no other clamp or fitting?

Just want to make sure I understand. I have never loved using the braided fuel hose, and buying the EFI rated stuff gets silly expensive.

Yes. I used the Mastercool hydraulic flare kit when I did mine. (it comes with push-to-connect dies)
https://www.mastercool.com/product/72475-universal-hydraulic-flaring-tool-set/
I really like the Mastercool kit. It can work with lines on the car, it can flare 45° brake lines, fuel lines, power steering stuff, bubble flares, etc. and it has no issues flaring stainless. The dies are rock hard tool steel and I have never had a line slip. Recently I purchased the 37° flares to make AN/JIC lines for the Cummins swap.


The nylon lines have no clamps or additional fittings, it's pure press fit on the hose barb. Some people have had success heating up the nylon line and pushing onto the barb by hand. I did not. I ended up buying the tool for pressing the fitting on. It takes some grunt.

[Gunnibronco]

Great thanks. We had a tool kit at the first body shop I worked at and made my brake lines for my full width axles. I can see getting a lot of use out of that.

[Mr. Lav]

ok so which is better steel or poly (I was told to stay away from poly) cause if poly will work I have the kit with gun at work, with the steel lines looking at the fittings they look like they go together like air brake lines. thanks Alex

[Digger]

You want to use steel lines (stainless) as much as possible. They make up the majority of the run between the tank and engine, and attach to the frame rails. But you need to make connections between the rail and the tank and the rail and the engine. That's where poly or rubber comes in.

Any time there is motion between two components, you need a soft line. I chose poly over braided rubber lines because it used OEM style connectors, it's tough and not very expensive. The OE's spend a lot of time proving something out, so if they are using push-to-connects and poly line, its good enough for my 50 yr old Bronco. Another ancillary benefit I had was being able to use off-the-shelf fuel filters from the parts store. (shown in the picture above)


AN fittings are also good-to-go. They have a well established history in military and industrial applications.

The least preferred option is hose barbs and hose clamps. They work okay, but hose clamp quality has gone way down with the flood of foreign produced parts, which can lead to leaks. I've started collecting hose clamps at the Pick-N-Pull because parts store stuff is pure garbage. Disassembly after time can be difficult and make necessitate cutting the line. Push-to-connects and AN fittings rarely leak, require minimum effort to install and are reusable.


That's my sales pitch.

[Mr. Lav]

Thanks everyone for the info, I'm going to use stainless and then poly for the soft line part of it.

[Gunnibronco]

I like Digger's logic. I'm using steel line with rubber (not AN) hose. The EFI hose is expensive and very hard to disassemble from the barbs without cutting it off. I'll be doing it with the fittings & nylon next time for sure.