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Cracking fuel lines? Just replaced 5 months ago!

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Old 01-22-04, 02:05 PM
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Cracking fuel lines? Just replaced 5 months ago!

Anybody have any ideas on what I can do about my fuel lines? I just replaced them less than 5 months ago with the highest rating I could find, and it's cracked and leaking all over my car now. Any idea's on what I can do to prevent them from cracking like this?
Old 01-22-04, 03:35 PM
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I'd start by not buying that brand again. Fuel line should last for many years.

Someone's bound to suggest you jump dump lots of money into SS lines, but that doesn't change the fact that this shouldn't happen.
Old 01-22-04, 04:19 PM
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Did you replace the stock rubber lines ?
IF yes, I don't see how they could crack so fast.

or

Did you replace the stainless steel lines (that go along the rail) with rubber lines ?
If so, depending on what you mean by cracking, I would think it would be a good idea to use stainless steel like the factory stuff or at least protect them with something.

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Last edited by hugues; 01-22-04 at 04:25 PM.
Old 01-22-04, 04:29 PM
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There are no factory SS lines.
Old 01-22-04, 04:32 PM
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Spend the extra money on SS braided. You know its 40hp right there.


Maybe you shoudl use some of that water remover? If there is water in there it may have frozen due to the temps dropping during the winter and the expansion from the freeze cracked them. :/


Santiago

PS- I use Good Year Fuel Lines. 0 < number of probs so far.
Old 01-23-04, 03:13 AM
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I'm not sure the brand, it was somethin like $12 a foot for their 55psi rated hose, but there's a huge split about 3" long that I had to replace
Old 01-23-04, 03:58 AM
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A FI hose should last years. Even the cheap ones should. Maybe it's rubbing against something to cause the cut? A small puncture would cause it to expand from the pressure inside the hose.
Old 01-23-04, 06:59 AM
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There are no factory SS lines.
Pardon my ignorance,
but what are the factory hard fuel lines made of ?

What about the brake lines ?

Can standard hard brake lines 5/16 be used for fuel ?

Just trying to learn something,
hugues -
Old 01-23-04, 08:58 AM
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Be sure you are using hose specified for fuel injection. Many of the part counter flunkies don't know that there are different standards. I paid $3 per foot for 5/16 FI hose at the local Pep Boys.

I once installed regular fuel hose on my jeep. Same thing happend to me. 60 days later I was leaking fuel all over. The stanadard hose won't tolerate the high pressure of FI and the hoses. It tends to "balloon up" causing the cracking that you and I have experienced.

Make sure the hose you get is marked "fuel injection".

Good luck,
Michael
89 TII
Old 01-23-04, 09:47 AM
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Well I replaced everything with braided but I went big (-8 to dual -6) to prepare for BIG turbo. However, I might suggest using aeroquips socketless hose and fittings. It has a tough nylon outer sleeve with rubber and reinforcements on the inside. Best part, it's light and you just push the hose onto the fittings, no wrenches..etc required. I used this setup for in the tank to hook up to my fuel pump and for a return. It costs about $2.50/foot tand he fittings are a little cheaper than the ones for the braided hose, plus this hose is good for pressures up to 250 psi. You also get to dump the old regulator and pulsation dampner...Wheeeeee.
Old 01-23-04, 02:11 PM
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Yeah, it's FI hose, even says 55psi all over it 'for fuel injection'
Old 01-23-04, 02:26 PM
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Maybe you just got unlucky? Try going to a different parts store and getting some hose there. I payed 4.95/ft for my stuff IIRC
Old 01-23-04, 03:47 PM
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Curious, do you have a functioning Pulsation Damper?
Old 01-23-04, 03:48 PM
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If that was for me the answer is no.
Old 01-23-04, 03:56 PM
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did you buy fule line made in the us? thats your problem, the stuff is so shitty you need to replace it every 15minutes, unlike the factory stuff which lasts for 20+ years.

earls used to make nice rubber fuel line, but stay away from gates, goodyear etc etc
Old 01-23-04, 03:57 PM
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uh good year lines are still perfect in my car.
Old 01-23-04, 04:13 PM
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If the question about the pulsation damper was for me. I have one, the screw backed out (didn't leak), but the o-ring and everything else looked fine so I put the screw back in. Kinda surprised it was backed out. The car has 45,xxx miles on it and this PD still has the gold coating on it...weird.
Old 01-23-04, 04:58 PM
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Strange how you recommend to stay away from Goodyear Fuel Line. I've had It on my car for 2 years now and it's no problem with me.

And to compliment NZConvertible's anti-suggestion, I too am In the midst of doing the full AN Fitting conversion.
Old 01-23-04, 05:08 PM
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Originally posted by cbrock
If the question about the pulsation damper was for me. I have one, the screw backed out (didn't leak), but the o-ring and everything else looked fine so I put the screw back in. Kinda surprised it was backed out. The car has 45,xxx miles on it and this PD still has the gold coating on it...weird.
cbrock, I remember Icemark saying that the screw should only be set to a specific depth, ie. too far and it will tear the diaphram and not far enough and the PD doesn't damp the fuel pulsations. I thought this could be the cause of broken lines.

FWIW, my car has about the same milage and because the engine was replaced with a rebuild I decided for safety's sake to replace the PD (it was still gold in color too). In my case I figured that after all that I had spent on the car so far there was no way that I was going to risk it all for the cost of a PD!

I'm not sure when or if the rubber lines in my car have ever been replaced, but I did inspect them carefully for cracks and splits before re-using them.
Old 01-23-04, 05:46 PM
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Originally posted by silverrotor
Strange how you recommend to stay away from Goodyear Fuel Line. I've had It on my car for 2 years now and it's no problem with me.

And to compliment NZConvertible's anti-suggestion, I too am In the midst of doing the full AN Fitting conversion.
i put some one mine as a return, and it was cracked and swollen 6 months later. ive used for other stuff too, and its just not nearly as good as the 15 year old mazda stuff
Old 01-23-04, 06:51 PM
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Uh, 55psi is a bit low.
The stock fuel system runs at 40psi under boost and +1psi for every psi of boost.&nbsp; So at 10psi of boost, your fuel system is seeing 50psi of fuel pressure!!!

All of the "FI' hose we use have rating at least into the 150psi to 200psi range.



-Ted
Old 01-23-04, 09:11 PM
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I think Ted's right on this one. 55psi leaves almost no safety factor. I know that's not supposed to be the hose's
burst pressure, but it's still a bit too close for comfort.

cbrock and silverrotor, are you guys clamping those big expensive lines onto the stock steel lines that make up a large part of the total length of the fuel lines? Just curious.
Old 01-23-04, 09:38 PM
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I'll be running the lines, In It's entirety, all the way to the Fuel Pump. Imo, their Is no sense to do just the Engine Bay.
Old 01-23-04, 10:06 PM
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Yeah, I've got 90 deg bulkheads that replaced the nipples on the fuel pump bracket and it's -8 up to the split where it goes to -6 to each rail and then a -6 return.

Here's the fuel tank mod. This single walbro will eventually be paired up with another walbro once the need arises.

Old 01-23-04, 10:57 PM
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Why did you go -8 AN to the Y-Split than taper off to -6 AN? At this rate, wouldn't have been preferable to go -6 AN all around? Or have -8 AN as a return?


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