Tweet
I just re-did my fuel lines with AN style fittings, and thought I would do a quick how to write up.
first, what are AN fittings, AN fittings are not aerospace fittings as many believe, the may be used there, but their origins are in the military, AN stands for Army-Navy. All AN fittings are sized in 1/16" increments, to find the inch size of an AN fitting, simply divide the fitting number by 16. Example, -4 AN would be a 1/4" fitting (4 divided by 16 is .25 or 1/4), or -6AN would be 3/8", ect. fitting sizes are typically between -2 (1/8") to -32(2"). All AN flare fittings use a 37* flare, which is not compatible with typical plumbing flare tools, which use a 45* flare. Flaring a tube for an AN fitting is no different than any other flare, just make sure you use a 37* flaring anvil/die set.
Another option, if you don't have flare tools available is to use compression fitting. The compression fittings use a Ferrule/lockring combination, unlike typical plumbing fittings, which use just a ferrule.
they install in a manner similar to standard compression fittings, just need to make sure the ferrule and lockring are int he right order on the hose or it won't seal. There are Ferrule setting tools, but most people just install the tube nut lockring, the ferrule, and then tighten them directly to the fitting. I've done this multiple times to no ill effect. I'll add pictures of the actual install process later (this week, maybe next week)
now, for the main event, hose ends.
First, push lock fittings.
Name pretty much says it all, this style hose end uses sharp serrations to grip the inner wall of the hose. No hose clamp is required, but the fitting only works with certain types of hose. The only way to remove a push lock fitting is to cut it off, for that reason, I consider push lock fittings a one time use fitting. to install, oil the barbed end of the fitting, and push it onto the hose, beware, it can be a bitch to get them on. No hose clamps are required, although it wouldn't hurt anything, a finished product will look something like this:
Now, re-usable hose ends for stainless braided hose:
First step, measure the hose, get the length where you need it and mark it.
Next, apply tape over the marked area, I usually go around the hose 3-5 times for a -6 hose, with the middle of the tape over the mark made in step one. I use electrical tape.
now, using an angle grinder with an abrasive style cut off wheel, cut the hose, go slow, it's not a race. straighter is better. DO NOT REMOVE THE TAPE!
once the hose it cut, DO NOT REMOVE THE TAPE! The hose it will be full of dust and crap from the cutting process, clean it out, you don't want to kill your new injectors, or clog your new fuel filter.
now, press the hose nut onto the hose, make sure it's all the way in the nut. if you removed the tape, you now see why I said not to in the earlier posts because now, the braid has opened up and it's hard as hell to get the nut over it...
(this picture sucks worse than bad, working on a new one...)
after installing the nut, mark the hose with the marker you used to mark your cut, this mark will be a baseline so you can see how far the hose pushed out of the nut, I haven't had a hose push out more than 2-3% anything over 5%, and I would start over
Next, I pour a little bit of clean engine oil into a small container (in the case, the cap from the oil jug) and dip the other end of the fitting into the oil to lubricate it as it pushes into the hose.
many people say to put the hose nut in a vice as you press and turn the hose end into the hose nut, I haven't had a vice available, nor have I needed one. from here, just press the hose end into the hose nut, and turn to tighten the fitting, taking care not to crossthread, tighten until the hose end bottoms out on the hose nut, don't tighten an further or you night strip the threads, or mar the finish on the fitting.
now, you think you're done, but there's one step left, I recommend pressurizing the hose to at least 1.5 times operating pressure with compressed air, and giving a coating of soapy water to check for leaks, especially for fuel lines, you don't want all this work going up in smoke...
I'll work on adding more pictures and info here in the next couple of weeks, hope someone finds this post helpful.
-262
Edit: Please excuse any inexcusable spelling or grammatical errors, I'm a wee bit drunk...
first, what are AN fittings, AN fittings are not aerospace fittings as many believe, the may be used there, but their origins are in the military, AN stands for Army-Navy. All AN fittings are sized in 1/16" increments, to find the inch size of an AN fitting, simply divide the fitting number by 16. Example, -4 AN would be a 1/4" fitting (4 divided by 16 is .25 or 1/4), or -6AN would be 3/8", ect. fitting sizes are typically between -2 (1/8") to -32(2"). All AN flare fittings use a 37* flare, which is not compatible with typical plumbing flare tools, which use a 45* flare. Flaring a tube for an AN fitting is no different than any other flare, just make sure you use a 37* flaring anvil/die set.
Another option, if you don't have flare tools available is to use compression fitting. The compression fittings use a Ferrule/lockring combination, unlike typical plumbing fittings, which use just a ferrule.
they install in a manner similar to standard compression fittings, just need to make sure the ferrule and lockring are int he right order on the hose or it won't seal. There are Ferrule setting tools, but most people just install the tube nut lockring, the ferrule, and then tighten them directly to the fitting. I've done this multiple times to no ill effect. I'll add pictures of the actual install process later (this week, maybe next week)
now, for the main event, hose ends.
First, push lock fittings.
Name pretty much says it all, this style hose end uses sharp serrations to grip the inner wall of the hose. No hose clamp is required, but the fitting only works with certain types of hose. The only way to remove a push lock fitting is to cut it off, for that reason, I consider push lock fittings a one time use fitting. to install, oil the barbed end of the fitting, and push it onto the hose, beware, it can be a bitch to get them on. No hose clamps are required, although it wouldn't hurt anything, a finished product will look something like this:
Now, re-usable hose ends for stainless braided hose:
First step, measure the hose, get the length where you need it and mark it.
Next, apply tape over the marked area, I usually go around the hose 3-5 times for a -6 hose, with the middle of the tape over the mark made in step one. I use electrical tape.
now, using an angle grinder with an abrasive style cut off wheel, cut the hose, go slow, it's not a race. straighter is better. DO NOT REMOVE THE TAPE!
once the hose it cut, DO NOT REMOVE THE TAPE! The hose it will be full of dust and crap from the cutting process, clean it out, you don't want to kill your new injectors, or clog your new fuel filter.
now, press the hose nut onto the hose, make sure it's all the way in the nut. if you removed the tape, you now see why I said not to in the earlier posts because now, the braid has opened up and it's hard as hell to get the nut over it...
(this picture sucks worse than bad, working on a new one...)after installing the nut, mark the hose with the marker you used to mark your cut, this mark will be a baseline so you can see how far the hose pushed out of the nut, I haven't had a hose push out more than 2-3% anything over 5%, and I would start over
Next, I pour a little bit of clean engine oil into a small container (in the case, the cap from the oil jug) and dip the other end of the fitting into the oil to lubricate it as it pushes into the hose.
many people say to put the hose nut in a vice as you press and turn the hose end into the hose nut, I haven't had a vice available, nor have I needed one. from here, just press the hose end into the hose nut, and turn to tighten the fitting, taking care not to crossthread, tighten until the hose end bottoms out on the hose nut, don't tighten an further or you night strip the threads, or mar the finish on the fitting.
now, you think you're done, but there's one step left, I recommend pressurizing the hose to at least 1.5 times operating pressure with compressed air, and giving a coating of soapy water to check for leaks, especially for fuel lines, you don't want all this work going up in smoke...
I'll work on adding more pictures and info here in the next couple of weeks, hope someone finds this post helpful.
-262
Edit: Please excuse any inexcusable spelling or grammatical errors, I'm a wee bit drunk...
Comment