AN -8 to steel hard line

Clubbs

Well-Known Member
Joined
Jun 15, 2008
Location
Blounts Creek
Rookie question: What's the right way to run flex line from a fuel cell (#8 AN) and convert it to hose clamp onto the hard steel factory fuel line?
 
What are you building that has a -8 feed? Most everything is -6. With that said I would likely just run the push lok style hose and hose clamp to the steel line.
 
Chris_Keziah said:
What are you building that has a -8 feed? Most everything is -6. With that said I would likely just run the push lok style hose and hose clamp to the steel line.
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This junk RCI tank I found has -8 for pickup and return. I figured clamping the push Lok was the general way to go. Thanks
 
That seems even easier. I like it!
 
Chris_Keziah said:
No different than if a faulty AN connection fails. Aint nothing wrong with hose barb and clamp, just aint as pretty as AN stuff.
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Unless your steel tube has a barb on it, clamping a hose over a smooth steel tube is asking for trouble imo.

Nothing wrong with barb and hose clamp, but I understood that OP had a RCI fuel tank with AN8 pick ups and wanted to connect that to the factory steel feed tube.

For that purpose the fittings I posted above would be the correct way to do it. You are free to use a pushlock/barb style hose or full blown AN deal between the tank and the fitting that I posted which goes on the factory steel tube, as long as you don't hose clamp something directly over the steel tube.

@Junkyard Dog gave a great answer. But not everyone has access to a flaring tool for steel lines. The fittings I posted above will work by themselves without any specialty tool.


Plenty of people do it wrong and are happy with their results. The problem is when fuel shit fails, you're putting your life, your passengers and your vehicle at risk. Same as brake stuff. The cost increase is minimal, so why cut corners ?
 
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I've used clamps and rubber hose before. Just flare the end of the steel to make a bubble. Same process as regular brake line flare, but stop after using the little bit or mandrel or whatever you call it, just don't fold the line back on itself like a double flare. The bubble will help seal and keep the clamp from blowing off.
 
Tim C said:
I've used clamps and rubber hose before. Just flare the end of the steel to make a bubble. Same process as regular brake line flare, but stop after using the little bit or mandrel or whatever you call it, just don't fold the line back on itself like a double flare. The bubble will help seal and keep the clamp from blowing off.
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I have seen failures when doing things like that. My first job out of college was engineer for the fuel division of these guys : Products | AKWEL

Lots of issues with not properly barbed connections were detected when doing reliability runs etc.

Of course you can do it wrong and never have an issue, but why ?
 
I like copper nickel line over steel,

I also like to just put a bubble flare on the end and then can push the line over and hose clamp or spring clamp it.

For permanent stuff, I like to use the gates heat shrink hose clamps instead of worm drive clamps.

Make sure any hose is efi and ethanol rated. Even better if it’s Teflon lined, but the fittings for those aren’t cheap, and the hose doesn’t rotate/twist so make sure the clocking of your fittings are correct when you install them, or add a swivel fitting inline.

Just don’t use any of the aftermarket jeep 4.0/ls style to AN quick connects with plastic retainers.

I haven’t found any that actually stay attached. Ex: I shoved the correct size hose over the nipple and past the retaining shoulder on the fuel rail, and used two hose clamps. One before and one behind the shoulder. Never an issue.
 
Bebop said:
Unless your steel tube has a barb on it, clamping a hose over a smooth steel tube is asking for trouble imo.

Nothing wrong with barb and hose clamp, but I understood that OP had a RCI fuel tank with AN8 pick ups and wanted to connect that to the factory steel feed tube.

For that purpose the fittings I posted above would be the correct way to do it. You are free to use a pushlock/barb style hose or full blown AN deal between the tank and the fitting that I posted which goes on the factory steel tube, as long as you don't hose clamp something directly over the steel tube.

@Junkyard Dog gave a great answer. But not everyone has access to a flaring tool for steel lines. The fittings I posted above will work by themselves without any specialty tool.


Plenty of people do it wrong and are happy with their results. The problem is when fuel shit fails, you're putting your life, your passengers and your vehicle at risk. Same as brake stuff. The cost increase is minimal, so why cut corners ?
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OP said factory steel line, ever seen one that came from the factory without a flare? I haven't. Not saying an AN flare or crimp connection is wrong but hose over steel barb isn't wrong either which is what your implying.
 
Bebop said:
Unless your steel tube has a barb on it, clamping a hose over a smooth steel tube is asking for trouble imo.

Nothing wrong with barb and hose clamp, but I understood that OP had a RCI fuel tank with AN8 pick ups and wanted to connect that to the factory steel feed tube.

For that purpose the fittings I posted above would be the correct way to do it. You are free to use a pushlock/barb style hose or full blown AN deal between the tank and the fitting that I posted which goes on the factory steel tube, as long as you don't hose clamp something directly over the steel tube.

@Junkyard Dog gave a great answer. But not everyone has access to a flaring tool for steel lines. The fittings I posted above will work by themselves without any specialty tool.


Plenty of people do it wrong and are happy with their results. The problem is when fuel shit fails, you're putting your life, your passengers and your vehicle at risk. Same as brake stuff. The cost increase is minimal, so why cut corners ?
Click to expand...


Nothing wrong with compression fittings and I think those are the answer for this app, but the most correct in my opinion would be to buy a backing nut and ferrule then flare the line 37*.
 
Chris_Keziah said:
OP said factory steel line, ever seen one that came from the factory without a flare? I haven't. Not saying an AN flare or crimp connection is wrong but hose over steel barb isn't wrong either which is what your implying.
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There are different types of barbs and what came on a factory steel line isn't engineered to be hose clamped over AFAIK. No time to go dig in the ISO standards etc but that's my belief.

Edit : If you have access, I beleive that SAE J2045-201211 is where the standards are laid out. I'm ready to be proven wrong but have no access to the documents either.

And I'm just hammering the fact that a rubber hose that's clamped on a smooth tube is a giant no-no. Since I don't know what his hard line looks like I'd rather talk about it. Maybe the OP knows all of this, but maybe not, or maybe someone will find this thread and think it's a good idea.
 
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Thanks for all the input everyone. For some clarity, the factory steel lines still have the original barb(s) on them. However, this is an 85 CJ7 which obviously came with a low pressure engine mounted fuel pump. The previous owner converted the jeep to fuel injection with the Mopar MPEFI kit. So it now has an external high pressure (38psi) pump all connected with rubber hose and clamps to the factory line. The pump outlet has the same hose barb configuration as the factory line. These barbs seem to be legit and there's no sign of leaks here in the 3 years I've owned it.

I do like the Earl's compression fittings, and I do have flare tools. Not sure why I didn't think of that earlier. Also agree with Chris that the factory barbs are likely sufficient in this application especially if it was still running the stock fuel system.

This whole plumbing project will be temporary anyway:

77GreenMachine said:
The tank will crack before the fuel lines fail anyway. Ask me how I know
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I got this tank out of someone else's unfinished project for $40. I'll mount it in the barnes bracket and make my last run this winter, but will hopefully finish the cad model of an undermount tank soon and get my cargo space back before the spring.
 
@Clubbs yeah it should get you by. Mine lasted a while and had been welded up once before I owned it. It cracked on me about a year ago and I paid the expert @mcutler to weld it up, so far so good but it's inevitable that it would crack again at some point.
 
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