SS Braided Hose Issue

[dive!dive!]

Folks,
I've recently converted to EFI (last Sept) and just now redone the fuel system again to add a feeder pump /swirl pot. In doing this, I have mostly -6AN SS braided hose and fitting throughout. In doing the conversion and swirlpot, I've made up some new hoses and re-used some from the carb installation - those would be about 2-3 years old. On firing up the pumps, I had two leaking hoses, made a mess, but replaced them and all seems well. I thought I take a look at the HP hose that leaked and stripped off the braiding. I was shocked at the state of the rubber liner - degraded and soft, splits easily if bent. I suspect the integrity would be ok if the hose wasn't re shaped, but I'm guessing my re-use added new bends and caused the split. Needless to say I'm now a little bothered about what might be inside the other hoses...especially as I can't remember which were 3 months or 3 years old, and the ones behind the shroud are a pain to get at....
Fuel has only been UK super unleaded.
Anyone else had a similar issue ?
And another question - any reason I shouldn't use hardline to connect my tank to my pumps /pot that are sitting on the frame head ?
Cheers
Steve

[BeetleBug]

Thank you for sharing,

1) Which brand hose?
2) How much ethanol is used in your UK Super unleaded fuel?

Best rgs
BB

[dive!dive!]

Lets just say its a well known UK supplier, I've put the question to them as well, and don't want to call them out unnecessarily....

Currently 5% maximum EtOH permitted in the UK...

[stretch]

I've had the same issue and I know of at least 2 other people who have had this problem.  Mine was caused it seems from the fuel lines being left dry.  The lines that contained fuel had no issue, but, the lines that were removed and stored 'dry' became porous over a winter.

[dannyboy]

i had same issue with lines that were used then reused have since switched to the blue aeroquip push on fitting hose and they seem to be btter so far...

[Dougy Dee]

Rubber liner? Should be Teflon. The costly stuff...

[dive!dive!]

Rubber liner? Should be Teflon. The costly stuff...

Maybe...the rubber stuff is sold as being compatible for all fuel types ....

[dive!dive!]

Thanks for the input chaps. At least its not just me then. I wish I knew this before I spent a lot of time and money installing this stuff. I mistakenly believed I was investing time/money to do a robust long lasting job. You all know how long it takes to get it fitting right. Its shocking to me how quick this stuff degrades - hardly fit for purpose. I'm guessing there are loads of vehicles out there with potential problems. Scary.
Even though its a right PITA I'm going to re-do again, just cant sleep knowing its not right.
I think I will put kunifer wherever I can (already have it on the long runs) and where I have to have flexibility (ie firewall to engine and engine to pressure reg) , maybe use the Teflon stuff.
Any other advice before I start would be appreciated.

Back to my question in the first post - I know OE had the flex pipe from the tank to tunnel , but why not have that hardline as well ? There is no flex required between the tank and framehead

Thanks
Steve

[dive!dive!]

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Well , that makes interesting reading. Wish I'd seen that a few months back.
12-18month hose life. Seems ridiculous to me.

[deano]

Before you re-use any braided hose, trying bending it with your hands into a "U" and listen to it.... If you hear any cracking inside, throw it away.

[Martin S.]

Someone told me that US made fuel hose was better than European fuel hose because it was 'flame proof' and I thought that didn't sound believable. The rubber hose available in here seems fine and I've never heard of a limited lifespan like what happened to you. That is horrible! It reminds me of what I was told about fixing the vintage gas heaters in VWs - Never trust the original steel braided hose on them because when they leak you can't see the leak easily and it can start a fire! Always replace with rubber gas hose. The disadvantage of the US hose is that it seems only to be available in inch sizes but here is a link... http://www.jegs.com/i/JEGS+Performance+Products/555/159210/10002/-1

[BeetleBug]

dive!dive!, I think you are not alone experiencing this and more will follow. If you are careful selecting your rubber hose (ethanol compatible) you can find a hose that will last longer compared to most AN hoses. Swedish tuners have years of experience with ethanol rich fuel and have managed to find high quality rubber hoses that last (Swedol/Trelleborg). A more permanent fix is to replace them with proper tubes and to only use hoses where it is needed. One thing to remember if you are going to race is that not all tech inspectors fancy ordinary hose clamps.

deano: good tip. The SS braiding make noises when you bend so you need to listen carefully if you want to identify that it is the rubber inside cracking.

Best rgs
BB

[dive!dive!]

One thing to remember if you are going to race is that not all tech inspectors fancy ordinary hose clamps.

No racing, but not a single hose clamp on my fuel system, everything is AN.
And that's the pain. I either try to find other rubber hose that will last more than three milliseconds or covert to Teflon where I cant use hardline. Trouble with Teflon hose is that its nowhere near as flexible and the fittings are totally different....

I find it totally cr*p that this stuff can be sold as fit for purpose....it blatantly isn't.

Oh well, an excuse for more garage time, we live and learn, thankfully its 'just' a hobby!
Cheers
Steve

[WhiteTrash]

Back to my question in the first post - I know OE had the flex pipe from the tank to tunnel , but why not have that hardline as well ? There is no flex required between the tank and framehead

Thanks
Steve

That was probably done to ease installation/quicker to assemble on the factory line. It would be more hassle to line up a pipe nut with seal to the thread on the tank and then tighten with a spanner, than slide a bit of rubber hose on and secure a couple of hose clips.
Time is money on the production line.

[Lids]

Back to my question in the first post - I know OE had the flex pipe from the tank to tunnel , but why not have that hardline as well ? There is no flex required between the tank and framehead

Thanks
Steve

That was probably done to ease installation/quicker to assemble on the factory line. It would be more hassle to line up a pipe nut with seal to the thread on the tank and then tighten with a spanner, than slide a bit of rubber hose on and secure a couple of hose clips.
Time is money on the production line.

As said it is so much easier to install a fuel tank with a rubber hose.

[dive!dive!]

Quick update on this.
I've re-done everything back to the engine firewall so far. I used 3/8 inch kunifer for everything , using tube ends with olives, each piece I made I hooked up to a compressor and leak tested to 10bar, so I reckon they are good enough. It was a bit of a fiddle to do the connections to the tank, but perfectly manageable.
There is one section I used Teflon SS braided hose as I needed the 150Deg end fitting because of space. I had not used the Teflon lined stuff before but wish I'd known about it at the beginning - it also uses a compression olive on the core but if anything is easier to assemble. The bonus is the bore is the same but the overall outer diameter is smaller. I'd encourage anyone to look at it in place of the traditional rubber cored hose as Teflon, should in principle last as long as a hard line.
I'm still shocked that the rubber stuff can have a 12-18mth life expectancy.....
Hope that's helpful.
Steve