Can anyone point me to some info on fittings?

Specifically i'm trying to find out:

-where to use AN fittings
-why to use AN fittings
-alternatives? pipe, straight flared, hose barb.... which to use when and why and how...
-if I wanted to hook up my fuel pump to my carb, and the stock steel line won't work, then I need a pipe thread in the fuel pump and carb? or 'normal' straight fittings with a 45/37/47 degree flare? use anything on the threads for either? pipe threads are classified by the size of the pipe, and flared fittings are...?

ugh, my head is spinning as I realize I don't know anything about these fitting sizes, and i'm getting really tired of the parts store guys knowing nothing, and I'm driving back and forth....

 

huh, found some info
Brake Plumbing Secrets Revealed!

I guess tapered pipe threads to hose barb is common for coolant hoses, and 45 degree flare is common on brakes and fuel for my car.... fair enough.

 

Hahaha fittings are fun


If your redoing your fuel stick to pipe thread, unless you like to be constantly tightening those AN fittings because their coming loose!

JIC (37* flare) has got to be the most retarded fitting that has ever been invented...

As for the sizing on the flare fittings they work on 16th scales.


-4 = 3/8"
-8 = 1/2"
-10 = 5/8"
-12 = 3/4"
-16 = 1"


Ill give you reasons not to use a JIC fitting...

For whatever reason they made that lovely 37* flare on the end it in no way mates up to a female perfectly. You actually only get a very very small sealing surface on a JIC fitting (as seen in my lovely pic i drew...) and with the vibrations they are prone to loosening off.

 

? I think my fuel setup uses straight fittings, ie 45 degree flare, as it is right now...


I think that's AN sizing isn't it? Flare looks like you refer to the OD of the tube, ie 3/8", then the nut is 5/8" fine thread. Pipe is goofy, the 1/2" fitting for my coolant is like a 3/4" hole, and uses an 11/16" wrench or something? and I need sealant? I think they used a 3/8" fitting behind my carb, for the brake booster (which I will cap, and just use the one on the back of my q-jet...)
oh, and I guess my passenger side cylinder head needs a 3/8" pipe plug too.... geez, all of this fittings stuff right at the very end of my motor build
oh well, soon enough ->

 

I was talking flare fittings as in 37* (JIC) & 45* flare. or most often referred to as AN fittings for an automotive application.


For others, Tube is measured by OD and hose is measured by ID.


Straight cut threads require use of some type of sealant, but a taper cut thread does not require any sealant at all and if its used can actually cause a leak in some cases!

 

-4 is 4/16, or 1/4"
-6 is 6/16 or 3/8"
and -8 is 8/16 or 1/2"


Pipe threads use sealant, 45* flares like on brake lines and power steering use no sealant. -AN lines use no sealant.

For anyone that's had an AN fitting or hose come loose and leak, you assembled the line wrong. AN hose is the only way to run fuel lines IMO if you stray away from the stock setup. Rubber hoses in fuel systems deteriorate quicker, are less resistant to heat and abrasion not to mention any more than 12" of rubber hose is ILLEGAL at any NHRA track and your car will not pass tech. I never use rubber line on transmission coolers either. The high pressure has a tendency to push the hose right off of the line that it's slipped onto. AN is expensive, but reliable and worth the $$$.

 

That's interesting. All my lines clearly have a corresponding 37 degree mating surface on the female end as well.

 

I think he's confused.

 

I'm just questioning the picture, that's all. I've had fittings leak because the male to female surface wasn't perfectly flush. Flaretite makes some pretty neat seals to fix that.

 

c'mon guys, this is what i do for a living...


A tapered thread should not use any sealant, a straight cut thread needs it to seal.


Now i think we do have a mixup with inverted flare (tube) and AN (JIC) fittings...

Please dont ague with me about the sealing surfaces on a JIC fitting, tighten the 2 fittings together and take them apart and check out the tiny little ring in about the middle of the flare, thats where it actually makes contact in the corresponding fitting. Now i dont have much experience with these in an automotive application but in the industrial apps these fittings are very prone to coming loose if ther subject to vibration (which is pretty much anywhere!)


The dash sizing in our line of work corresponds to the ID of the hose, once again -4 = 1/4", -8 = 1/2", -16 =1" and so on...




Stekman, I will shoot an E-mail over to our Aeroquip trainer and see if he can dig me up a picture he uses for the training. I know he has a great picture showing how the 2 surfaces actually mate. And for whatever stupid reason they dont make the whole flare contact instead of the crappy little ring.

 

ok sweet, so now you can see why i'm confused? Now there's differing opinions here....

Now I thought AN was different from 37* and 45* altogether? And they used very shiny fancy aluminum anodized fittings? Is it a tapered or straight thread?

Now it looks like the straight fittings like on my brakes didn't have a sealer, do they need it? It looks like the tapered pipe ones like on my intake for coolant, well, not sure, so I put some on...

 

So are you saying that an NPT threaded plug, fitting or whatever needs no sealant? yeah........

I'm right there with you on the contact area on the AN fittings. Never had one leak or come loose though if it was assembled correctly.

AN hose systems were developed by the military, (AN = Army/Navy). They're used in super-high pressure hydraulic systems in high heat, temperature and vibration areas. I don't understand how you can say that a rubber hose could possibly be more reliable in an automotive situation. Not to mention how many cars use AN hoses for brake systems in 800 psi + situations.

 

[QUOTE=84z28350]c'mon guys, this is what i do for a living...


A tapered thread should not use any sealant, a straight cut thread needs it to seal.


Now i think we do have a mixup with inverted flare (tube) and AN (JIC) fittings...

Please dont ague with me about the sealing surfaces on a JIC fitting, tighten the 2 fittings together and take them apart and check out the tiny little ring in about the middle of the flare, thats where it actually makes contact in the corresponding fitting. Now i dont have much experience with these in an automotive application but in the industrial apps these fittings are very prone to coming loose if ther subject to vibration (which is pretty much anywhere!)


The reason for the small sealing surface is to allow for a mild misalignment of the fittings and still have a secure seal. If the contact surface was larger then every connection would have to be perfectly aligned to seal, which in the industrial world doesn't happen to often. It also allows for a more positive seal ie the small sealing ring on a valve to seat surface in your cylinder head.

 

Flared fittings never need sealant, and should never have sealant.

The contact area between the male and female halves is small for a reason. A larger contact area would require more tightening for the fittings to put the same pressure on each other.

If you can't get an AN hose to seal, or to stay together without vibrating apart, you're doing something seriously wrong.

"AN" stands for Army/Navy. About 70 years ago the military decided they wanted their aircraft to use standardized fittings and hose to cut costs, and this is what they came up with. You can be certain that vibration in WWII-era combat aircraft was at least equal to anything you'll find in an industrial setting. After the war the huge surplus market became a source for hot-rodders, which led to the popularity of the fittings. It was the automotive aftermarket that started the fancy anodizing in red and blue, the original military stuff was probably boring olive-drab.

 

ok, i'm thinking conventially here, low pressure, low "corrosivity" I can use a hose barb, and nice cheap rubber hoses. This will probably use a tapered thread into the object to plumb.

more corrosive materials, higher pressure, I use a hard line, with a straight fitting.

AN fits in the middle here? A really expensive rubber hose with a fancy sheath on it? And holds higher pressure?

 

Going to AN fittings with the rubber hose with a fancy braided cover would be just for looks. IMO if you cant plumb a fuel system with tube and a foot of rubber line you really need to spend some time on your projects. Running the braided hose looks pretty cool but in the end all you have is a fancy rubber line that will deteriorate just like any other except that its a bit more abrasion resistant.


If you want something that you dont have to worry about leaking when you pull it out of storage every year run tubing as much as possible!

 

Flared tube is suitable only for so many disconnections and reconnections before it won't seal anymore. Look at how many people have problems getting their stock transmission cooler lines to seal.

If you want something that you don't have to worry about leaking when you put it back together, use AN fittings. You don't need to use braided hose though, there are a number of legal reinforced rubber hoses available.

 

Stick to what you know about plumbing in industrial applications because you clearly have no idea about the uses and advantages of AN hose in a automotive application. Or maybe you should find another field all together since you can't manage to make an AN fitting seal

 

For clarity:
1: SAE: 45` - Pneumatic, water, LPG.
2: JIC: 37` - Hydraulics on civilian equipment.
3: Inverted flare: low pressure fuel and low pressure hydraulics (ie: fuel connection on a Qjet and brake tubing)
4: Oring tube fitting: (ie: TPI fuel hoses, powersteering pressure hose)
5. NPT: tapered pipe thread (ie: coolant connections to heater on manifold)
6. AN: 37` Class 3A/3B UNJ/UNJF (radiused root threads) - Military and race.
The only fittings that require sealant are tapered pipe thread. (if you look at factory equiptment, ALL pipe thread joints will have sealant)

In defense of the lowly JIC fitting, you will find it on 95% of mobile hydraulic systems. Forklifts, backhoes, cranes, bulldozers, tractors etc. If it moves, has hydraulics, and was built after 1970, it is plumbed with JIC fittings and hoses. JIC was introduced as an improvement to the WWII era SAE fittings to allow sealing of higher pressures by changing the sealing surface angle.
A short time later, the adapter fitting business exploded.
EDIT: Corrected incorrect statements.

 

thank you supervisor!
so 45* = AN ? what degree is inverted flare? I thought they were 45*?

 

It is 45`because you use the same flaring tool as SAE to flare the end of the tube as non-inverted flare.

 

come again supervisor? what's non inverted flare?


is AN just meant for a flexible hose, or can it be hard line as well?

 

Non inverted flare=
A regular SAE flare fitting. Like copper tubing with a nut that covers the flare.
"AN" fittings are most common on the end of a hose but can be used for tubing runs. Aluminum tubing almost always has AN fittings on each end to prevent vibration related fatigue, a big problem for aluminum. The AN fitting supports more of the tube away from the flare as opposed to the inverted flare nut which only grips the flare at the end of the tube.
Inverted flare tubing connections are most common between cast parts that do not move in relation to each other because they can thread directly into a casting eliminating fittings at each end. Like fuel pump to Qjet.
EDIT: Changed incorrect statements.

 

ok thanks. so an inverted flare fitting is on my fuel pump to q-jet. I know what those look like, how they clamp the flared part into a fitting.

any AN fittings on my car right now? So I can see one?

 

Factory setup is a metal tube, slide a nut on each end of the tube and flare each end of the tube. One end of tube screws into fuel pump, other end screws into carb.
There won't be any AN fittings from the factory that I know of. They are easy to spot. They will usually be anodized aluminum, blue or red.
Most AN fittings are ALUMINUM. That's why they were military surplus (aircraft) and why racers love them (weight)
EDIT: Learning new stuff about about AN fittings. They are neither the same as JIC or SAE. The lowdown from the fitting people themselves: http://www.parker.com/tfd/fittingsol...ANFITTINGS.pdf
Second EDIT: Removed incorrect statements.

 

AN fittings are 37 degree, not 45.

 

Yep. I got my wires crossed by looking at thread pitch numbers.
Now, how do I clean up the mess? edit-edit-edit

 

Just to make it annoying, what's normally called "SAE" flare is 45 degrees, but SAE also adopted the AN/JIC stuff as a standard, so really there's SAE-45 and AN/JIC/SAE-37.

 

Clearly the people in charge of standards never talked to people that just ask "what kind of fitting do I need to hook up this hose?".
Their reply:
SAE J514/ISO8434-2 with Class 2A/2B, UN/UNF Series threads that conform to MIL-F-18866 as shown on MS51500 through MS5134.

 

aha!

Legris : 37° flare couplings to ISO 8434-2

So, bringing this back, how can I use an AN fitting on a flexible (ie, not hardline) ? I can't flare rubber tubing last I checked, and is braided just for looks and abrasion resistance, or is it fair game to use between my carb and fuel pump?

I had a few kinks in my 3/8" steel hardline from fuel pump to carb, and I've gone through about 3 now, I keep kinking the damn line! CHEAP POS princess auto $6 bender! Anyway, I was hoping to run a soft line, if possible...?

 

Braided is just fine between the fuel pump and carb, as are a number of approved non-braided hoses.

By the way, the bender to use is something like the Princess Auto 2910677.

 

Also... in the link you've posted above, that's just a regular tube nut and sleeve, not anything special.

 

Use aluminum line. Muuuuuch easier and cleaner to bend. Carquest sells a nice one. I have it and bent my new 5/16 steel trans lines with it. Works great. Does 4-5 different sizes up to 3/8. I think it was $20.00.

 

yea, i've never done that type of fitting myself, i've done some inverted flare, where the nut doesn't also need the sleeve... I guess that's part of the difference between inverted flare and AN.

Apeiron, can you list off an approved hose type, or where I might purchase it? I know a rubber line wouldn't work, or is dangerous, but what other choice do I have?
Can I use an AN fitting on a non metal line? Ie, a rubber or otherwise?

ah, ok, I have 2920119. The one you listed shows the angle you've bend to. If I can get a 90* bend without a kink it's worth trying I guess.

 

You can put any kind of hose end on any hose, as long as the end you're using was designed for the hose you're using.

Aside from braided stainless hose, these pushlock hoses are NHRA-approved:

Aeroquip: FC300, FC332, Star Lite 200, AQP Socketless
Earl's: Prolite
Gates: LOL Plus
Goodridge: 536, 710
Russell: Twist-Loc 836 and XRP HS-79
Dayco: Nylo-seal tubing.

 

alright, i'll be dropping by crappy tire to see if they have any of those, but I doubt it. Then i'll be trying mopac.

I'll have to get them to show me how to assembly a hose fitting on a soft hose, that throws me off. That flash animation on that webpage showed an AN fitting on a flared hardline, soft line I can't picture that. We shall see, thanks.

 

Canadian tire won't have any at all, and Mopac likely won't have any in stock. Gregg distributors might be a better bet, some of that stuff is regular industrial hose rather than racing stuff.

Soft line doesn't get flared like in the animation. A fitting which has the flare inside it is attached to the end of the hose. How the fitting attaches depends on the type of hose it's designed for. With braided stainless hose, a threaded collar is forced onto the outside of the hose, and then the fitting end is screwed into the collar and hose. The hose is squeezed between the two parts and held in place. Socketless fittings usually have some sort of a cutter that bites into the hose making it impossible to get the fitting off without taking a chunk of hose with it.

 

finally got around to this.

Went all the way to greggs. They had some -6 AN hose, but they had the braided stainless stuff for $11/ft, or some other kind of heavy duty stuff for $3/ft. They assured me either would work for fuel, and high pressure....
I got the $3/ft stuff, it was aero quip, and buddy said that the AN line that uses a threaded fitting on the end is the SS braided stuff only, the stuff I got you can only use a hose nipple and hose clamp....
they gave me a hose nipple - NPT thread, then an NPT thread - AN thread adapter... They weren't quite clear on what I wanted... So I ended up using a few 3/8" nipple - SAE male swivel adapters. They don't leak, and look pretty good. I'll see if this clears up my top end stutter.
Thanks.

 

Buddy was half right, then. The AQP hose takes the ever popular red and blue anodized AN fittings, but there are other AN fittings for their other hoses.

At places like that, it's a lot easier to look up the parts you need in the catalog first and just give them a list of what you want.

Depending which stuff he gave you, it might not be allowed if you plan to run at the track.

 

hmm, ok. I didn't exactly break the bank doing this mod, maybe $30 including the gas and new the new fittings I got from C-tire, so if it works I know it was a kinked line in the first place. Then I can look into other ways to do it.
I'll try and find the Aeroquip catalog online and see what I could have used..

ok, i've got AER 2556-6 line. Gear clamps on a c-tire brass hose nipple-straight SAE. Is there a way to know if this is legal? Or for that matter, what combo of fittings would be legal on this hose? (preferably without going to the flash style of braided hose, AQP I guess, since it would look VERY out of place on my car...)

Yea, I still need a battery hold down too, but I can't use anything due to the oversized battery i'm running. I'll have to get creative.

 

Useful catalogs:

Eaton Aeroquip Performance Catalog
Eaton Weatherhead Brass Catalog

All Eaton Documentation

Last I looked only the FC300, FC332, Star Lite 200, and AQP Socketless are the only non-braided hoses from Aeroquip approved by NHRA.

 

aww crap - I mixed up SAE 45* and inverted flare. I asked him for an SAE 45* end (which is what I got), when I really wanted an inverted flare... well, that explains that.

thanks for the links - you beat me to it.

 

ok, just a last minute sanity check

-FC 300 hose - say 4'
-190111-6S funky adapter goes on carb side, with socket #1212
-190235-6S on fuel pump side, with socket #1212.

I'm assuming the socket is used in conjunction with that adapter, but no other gizmos in there eh?
5 parts in total. That would be the FC300 setup, others being similar.
This right?

 

You're not planning on using a fuel filter?

 

?
Yea, that's still in the carb. Those fittings would connect to the carb - the 5/8-11 thread, with the filter behind it.
Or is an in carb filter a big restriction? (can I use one before the fuel pump?)