Teflon fuel line, Carbon lined really necessary?

[GSLENK]

I am about to fix all my crappy AN fuel lines (nylon braided, "rubber" core) with gasoline proof Teflon core stainless lines. I have searched for the best and so far, many upper end builders recommend carbon lined stuff (I think that's what its called, whatever its called, you know what I am talking about now).

I will also be replacing my crappy failing push lock (quick disconnect) methanol lines. Will I need the same type (Carbon lined) Teflon lines?

I am hell bent on Teflon lines, just I am not sure if flowing gas can really create that much charge on the Teflon, and spark internally and explode.

Anyone running either meth or gasoline through regular Teflon lines without issue?

BTW this carbon lining stuff seems to be on average twice the price of name brand type line without the internal coating...

 

[yokotabrat]

I went with the carbon impregnated ptfe hose just recently(got it from pegasus). It was very easy to work with and the corrugated inner core made it easy to route around everything. I'm sure there's quite a few people running the non carbon impregnated stuff, but I didn't want to risk anything with my fuel system.

That probably doesn't help you much, but honestly it'll probably just come down to whether you think it's a safety issue with standard ptfe hose.

Also, I think most of the ptfe hose out there isn't corrugated, so it makes it harder to work with since the bend radius is quite a bit larger.

 

[pksystems]

Old thread, but seems to fit...

I picked up some Aeroquip Teflon race hose and was going to replace the flex sections of my fuel lines.

After doing some more research I was finding threads stating you NEED the carbon inner liner to properly ground the line against static electricity, which WOULD cause pinholes.

On Aeroquips site they state this hose is good for pretty much everything, including fuel. If it's the fuel flowing through the line that causes the static build up, what exactly is this hose for? Fluids with little or no movement (brake lines).

I was going to use it for my power steering line aswell, but wouldn't that have the same static build-up?

Anyone used non-grounded teflon fuel lines without issue? I've seen it sold on several sites as fuel line.

Is it marketing to sell a different product, or is it a real issue?

 

[yokotabrat]

I know I've heard of a lot of people running the non carbon impregnated PTFE hose and not having any issues.

From the research I did, it seemed to be a Mil spec and aviation requirement to have the carbon impregnated hose for safety reasons. They are obviously designing with a lot more safety in mind than most other industries, so for us it becomes a more economic decision.

I chose the peace of mind of the carbon hose for my fuel lines so I'll never have to worry about it ever again.

For the power steering hose you have to be more careful. That system is under much more pressure than a fuel system. As long as the hose you choose works with the special high pressure compression type fittings, you should be fine. I went with Russell PTFE lines and fittings designed specifically for power steering for the high pressure side. The low pressure side, I just used push lock hose or standard an hose.

 

[GSLENK]

I thought the carbon lining was because you do not want static electricity (sparks) mixing with fuel. Since so many people have done it without, I decided to go ahead and use regular taflon line. "Permeates"/smells-through a lot less than the regular rubber/nylon braid hose.

Been on for quite a while now pump to rail and back. No issues so far. I'm happy.

If assembled correctly, I think these hoses can handle the pressure of power steering. They do make the power steering adapter etc... Also, the place I buy the hose from calls it power steering hose (teflon etc...), I just use it for fuel.

 

[yokotabrat]

The carbon lining is to provide a path for the built up charge inside the hose to safely dissipate before arcing through the teflon to the braided shielding that's on the outside of the hose and causing small holes in the teflon. Not saying that I've ever heard of that happening in an automotive application, but who knows.

I don't think it's the hose that can't handle the pressure of a power steering system, but more the fittings and how the hose interfaces to that fitting. My power steering fittings used a ferrule type system similar to a compression fitting rather than the standard an fitting that's just pushed onto the hose end.

 

[curt-s]

..how and where is the gasoline going to ignite (what is the initial ignition location), and exactly what location is the static electricity going to be a problem at?

 

[pksystems]

Supposedly it forms pinholes when the static shorts through the teflon to the Stainless braid. Then it could ignite from the fuel leak.

Most of my searches on this kept coming up with the same company that was one of the first to add the carbon into their teflon inner tube. That's why I was asking if it is marketing. They were on several forums telling of the dangers of non-conductive teflon. Now Buy our product.

Just ordered some Fragola 600006 teflon hose & fittings. It is conductive.

 

[curt-s]

That's what I'm wondering about.. it sounds like "they" believe the ignition comes from within the line itself, which seems unlikely for most conditions. If the hose was empty, then maybe you'd have your source of oxygen for combustion, though. Hmm.. are there even enough joules in static to punch holes through lining, nevermind the insulator itself..

 

[crimsondragon]

I run Fragola line. Very easy to work with. Not as bad as some people make it out to be. I used a flat screwdriver to spread the braid to fit the olive on. After starting my car and finding a pinhole leak at the line from the filter to the rail, I replaced that with the same type of line I had left over. That in turn caused more leaks to form at the line from the tank to the filter and the rail to the AFPR. I decided it was a huge fire hazard to run that line anymore and replaced everything with Fragola PTFE. And that new line I made for the filter to rail, you could already feel it start to wear out when i removed it after a week of being in the car.

 

[daren_p]

I've ran Earl's Teflon lined SS hose from the rail to FPR for probably close to 10 years now. I initially switched because I hated the fuel smell you would get with reg synthetic lined hose. I can't recall if the hose is carbon lined (I'd guess it's not) but no issues here. When I called Earl's, this was the line they recommended for fuel.

 

[GSLENK]

I switched for the same reason (I swear that smell does permeate the rubber hoses, others disagree, but my nose wins for me...). 10k+ miles and no blown up car. I think that static electricity is probably for some over engineered military aerospace jet fighter tech. I couldnt justify doubling or tripling the price for carbon so I kept to regular. I get mine from a speed shop on ebay and I have yet to get a leaky fitting.

For 6an, I cut it with a angle grinder and cutoff wheel, then clean the PTFE "burr" with a razor blade. Then shove a 1/4" entension in the hole (a few of mine fit perfectly) to fix any minor out of round, and keep the shape while I pry away the SS braid. Insert the olive easy peasy, then press it together. Use a vice and big wrench to tighten it up. Never get a leak.

I try to use ptfe exclusively. For the price I get it at it pretty much costs the same as big name nylon braid.

One thing I do also is order 3:1 shrink wrap usually the cloth looking kind. It makes very clean lines that do not scratch surfaces for much less than buying nylon/cloth wrapped SS PTFE line.