Teflon vs rubber fuel hose.
 

I have been searching about this for some time now and just wanted to share for those of you who don't know.

I am running Teflon fuel lines with parker fuel fittings which are similar to this due to Mr Garfinkle.
Attachment 715904.Attachment 715905

About a year ago Mr Garfinkle told me to use Teflon hose and steel fitting because the standard fuel line and fittings where XXXXXXX i rather not say. I didn't ask questions i just did what he suggested. I never though it mattered whether it was Teflon or rubber, a fuel hose is made for fuel right??

I started searching about fuel lines my self because I found the standard rubber braided fuel hose basically rotted in a car I was working on. The car was sitting for a few years with 3 year old -8an SS fuel lines and when i removed them they where all mushy and gooey basically useless. Although the car was sitting around these fuel lines should not deteriorate like this.
Right before i found This hot rod magazine article i was thinking about the effects of these rubber hose rotting over the years and particles clogging up your fuel system.
http://www.hotrod.com/techarticles/e...ses/index.html

Unfortunately i never took pics of the my fuel lines or the fuel lines from that car i was working on but i just wanted to share my little story and my opinion of why Teflon hose is superior.

What source did you use for your teflon fuel lines?

aeroquip's manual specifically says to plug hoses when being serviced. when the fuel is exposed to air it oxidizes. the oxides attack the rubber hose.

also look at an oem car. the rubber hoses tend to outlast the metal on the car :P

teflon is good stuff, but i dislike the fittings that come with the hose ends. i only use teflon on high pressure stuff such as power steering.

I work for the largest distributor of Gates Hosing in the world, I'm currently learning A LOT about hosing & fittings.

Teflon or PTFE material based hoses are nonreactive, so they don't brake down over time due to exposure.

I'm still learning, but if anybody has questions regarding various hoses & fitting let me know, I have access to answers (all hose manufacturers, not just Gates$

There are some flaws in this article. First of all, it's Hot Rod magainze which already has its share of Luddites among the readership. Getting fuel injection advice from a carburetor magazine is already dicey. But first I will agree and say yes, it is true that there are some low quality Chinese stainless braided line and fittings.

But the main problem is that it was poorly researched. It sets up a "hierarchy" of fuel lines. The crappiest are really old fuel lines from a long-gone era of carburetors. Well that's obvious. Then it says SAE J30R9 spec (normal fuel hose) are improved over old rubber (of course), and J30R12-spec is even better. Except if the author had actually read the SAE standard he would see that there aren't even any specific ethanol degradation specs for J30R12 hose listed in the specification paper. It makes me think that he is just parroting what some sales rep told him. If you want to see the full J30 version 2 specs, send me a PM.

All the normal auto part store hose you get that usually says "J30" on it has been engineered to withstand E15 under reasonable use. During testing the hose is completely immersed in E15 fuel for 70 hours and then must meet a minimum standard for deformation.

https://www.rx7club.com/attachment.p...1&d=1293335630

When you read the acceptable tolerances, on paper it may look like a lax standard. But there are many 20+ year old properly maintained cars with original fuel lines today. If you let fuel sit in the lines for years then yes there will be problems. And if you use E85 with Autozone fuel line then yes you may eventually have a problem over the long run.

In the magazine article it shows a couple lopsided-looking comparison tests (carefully scaled bar charts) that show the teflon hose is better. Well I don't doubt that expensive teflon braided line is better than hardware store fuel line for withstanding ethanol-formulated fuel. But it's like comparing, in a drag race, a stock FD to a stock Civic or a stock C6 Z06 to a stock Civic. If you're trying to beat a Civic a Z06 will perform better than an FD but that doesn't mean the FD won't easily get the job done.

Is the teflon hose better? Yes. Do you actually need it? Probably not. In fact, I still have a few sections of original 23-year-old fuel hose on my 2nd gen, and that's probably seen E10 for at least a decade.

I am trying to find -10an Teflon line and fittings for my turbo oil return line but it sucks i cannot use Teflon for coolant because they don't stretch on the coolant nipple like rubber.

Another FAQ worthy thread. Filed it under the F section.

Here is the aeroquip pdf which mentions rubber hoses should not be left open during service(page 8, last paragraph). There is some other useful information in the pdf regarding hose construction.
http://www.scribd.com/full/45999675?...9dfgwmcgv810m8

I hope i am not violating any forum rules by quoting people in other forum but this is just one of many opinions i have read simply by surfing the web in different forums.

many people use rubber fuel line for years with out problems but how can i trust a rubber hose that will deteriorate on me if i simple forget to plug it off.It doesn't make sense.

no hose is idiot-proof, but the expensive teflon stuff is a lot closer to it than Autozone fuel hose meeting SAE J30 specification. Based on these SAE J30 specifications I am of the opinion that regular hardware store hose is fine for most applications.

But if installing expensive teflon hose and any associated fittings makes you feel better, you have to ask yourself what's the highest price (in time and trouble) that you are willing to pay for your personal peace of mind?