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Aeroquip hoses & fittings

lostpilot28

lostpilot28

Well Known Member
Why is it so hard to find a steel braided hose with steel fittings for FWF use? After reading the multitude of threads here and on other sites, I'm sticking with aviation specific fuel lines, but I'm building my own. I can find non-steel braided (Aeroquip p/n 303) hose with Steel fittings, and steel braided 701 hose with aluminum fittings.

Anyone know where to get steel braided aviation hose with steel fittings? I don't really care about brand so much. I can't find the right size with brands other than Aeroquip.
 
Thanks, Anthony...I want to build my own hoses. I was under the impression that TSFlightlines just builds hoses. Any other sites with prices listed?
 
lostpilot28 said:
Why is it so hard to find a steel braided hose with steel fittings for FWF use? After reading the multitude of threads here and on other sites, I'm sticking with aviation specific fuel lines, but I'm building my own. I can find non-steel braided (Aeroquip p/n 303) hose with Steel fittings, and steel braided 701 hose with aluminum fittings.

Anyone know where to get steel braided aviation hose with steel fittings? I don't really care about brand so much. I can't find the right size with brands other than Aeroquip.
Click to expand...

I've built several steel-braided hoses with aluminum fittings for the RV-6 and haven't had any service problems for the past dozen years, even after reusing some of the fittings when rebuilding hoses due to service life. It appears aluminum fittings are the norm for the auto racing community.

But I can't provide a source to answer your question.
 
I agree with post #4 and have made my own hoses from Aeroquip 303 and 491 fittings for 9 airplanes with no problems. I can warn you that some of these hoses are difficult to put together and the larger they are the harder, -8 and -10 sizes being quite a task with hand tools. The 303hose is steel braded but also covered by a cloth outer braid. If you will be using fire sleeve in the engine bay you don't see the nice SS brade of the other hoses anyway. You will also need the proper tooling to cut and assemble the hose. Always, always use aircraft quality proven hose and fittings in the engine area, none of the auto/race car stuff will do.
Jerry
 
Are they AN or JIC industrial?

Or are they industrial fittings?
From a Parker Aerospace publication:

"AN flare and 37 degree industrial flare fittings appear to be functionally interchangeable, but they are not. The most notable difference is in the threads. AN fittings use a increased root radius thread ("J" thread) and a tighter tolerance (Class 3) to achieve a 40% increase in fatigue strength and 10% increase in shear strength.
These two fittings function the same, they look the same, AND the industrial version is much less expensive to manufacturer. The problem is that the industrial version is 40% weaker."

It may be that you know and are content that you are being supplied with JIC fittings instead of AN, but if you want an "AN" fitting, worth asking the question from the supplier.

Perhaps TS Flightlines can wade in here.

Bill Brooks
Ottawa, Canada
RV-6A finishing
 
C-GRVT said:
Or are they industrial fittings?
From a Parker Aerospace publication:

"AN flare and 37 degree industrial flare fittings appear to be functionally interchangeable, but they are not. The most notable difference is in the threads. AN fittings use a increased root radius thread ("J" thread) and a tighter tolerance (Class 3) to achieve a 40% increase in fatigue strength and 10% increase in shear strength.
These two fittings function the same, they look the same, AND the industrial version is much less expensive to manufacturer. The problem is that the industrial version is 40% weaker."

It may be that you know and are content that you are being supplied with JIC fittings instead of AN, but if you want an "AN" fitting, worth asking the question from the supplier.

Perhaps TS Flightlines can wade in here.

Bill Brooks
Ottawa, Canada
RV-6A finishing
Click to expand...

The Aeroquip Super Gem fittings I linked above are AN. Be aware that Aeroquip sells an industrial grade (JIC) line of Super Gem fittings as well, if you are concerned about sticking with AN.

In 25+ years of using automotive/racer grade Aeroquip/Russell/Earls fittings in automotive applications I have yet to have one fail, but I got paranoid on my RV build and bought aviation-spec firesleeved hoses.

I have a PDF version of Aeroquip's 666 hose & Super Gem reusable fittings brochure.
 
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Lars,
you are right - there are "Super Gem" AN and JIC - it is confusing unless one knows that, because sizes are often quoted as "AN", even for fittings that are JIC.
The prices are telling - your link shows prices more than $double for the true AN fittings. I wonder what Summit and other racing and similar shops supply?
Like you, I intend to use AN fittings. JIC may be fine to use, but doing so should be a matter of conscious decision, not because of not being told what was being supplied.
Bill Brooks
Ottawa, Canada
RV-6A finishing
 
Hey guys, as a follow up I really want to give a huge thumbs up to Tom at TSFlightlines.com. I'm ordering the parts I need from him and he's been fantastic to work with. If I would've just started there in the first place, I could've easily saved several hours of research and online shopping.

If you value your time, just contact Tom.
 
C-GRVT said:
Lars,
you are right - there are "Super Gem" AN and JIC - it is confusing unless one knows that, because sizes are often quoted as "AN", even for fittings that are JIC.
The prices are telling - your link shows prices more than $double for the true AN fittings. I wonder what Summit and other racing and similar shops supply?
Like you, I intend to use AN fittings. JIC may be fine to use, but doing so should be a matter of conscious decision, not because of not being told what was being supplied.
Bill Brooks
Ottawa, Canada
RV-6A finishing
Click to expand...

I've (gasp) used a few JIC fittings on my plane. Steel, as it turns out, US-made Parker fittings. Specifically on my oil cooler. I use lots of JIC fittings and hoses in a fairly (actually extremely) harsh environment, on a 400Hz, 15g hydraulic shaker with oil at 4000 psi. Again, no fitting failures (though we have lost hoses). One time I examined a few of those -8 90? JIC fittings and compared them to a known AN fitting of the same type and size, under a 10X optical microscope. I could not discern any difference, though with good enough measuring equipment you may well catch it. In any case, based on my work experience I'm ok with those.

That said, I've bought a lot of stuff from vendors like Summit Racing over the years; it irritates me that any and all 37? flare fittings are described as "AN" when I'm almost certain that they aren't. In fact my Eaton Aeroquip automotive catalog that I have on my desk right now describes everything as JIC/AN, what ever that means.
 
Lars- and others-

Most all industial fittings are manufactured to meet a specific SAE specification. Aircraft/aerospace fittings are manufactured to meet AN/ NAS specifications. Although similiar in appearance and function, there are some minor differences; generally in materials and thread machining tolerances.
For experimental aircraft applications, a good quality industrial fittings by known manufacturers are quite sufficient.
Where I find that guys get in trouble is purchasing fittings from the "clearance" houses that market their fittings as "AN". It might look like it, smell like it, but not necessarily be AN grade. This is especially true in aluminum fittings. There are some that are made from 'AN' spec aluminum, such as Earls. I suspect that Aeroquip's Performance fittings are also. Most 'race car' fittings that the aftermarket suppliers have may not have AN nuts and stems. That doesnt mean they are junk, it just means that they aren't AN quality. Most also print a disclaimer like" not approved or recommended for aircraft".
Most stainless fittings are 304 or 316, which is way overkill for experimentals. Alot of them are made to AN spec, as far as materials and tolerances, just not certified as AN.
 
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