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Discussion Starter #1
I dunno, I don't really consider myself anal, but I'm not diggin how all of my fittings are sticking way out of everything on the npt side. I thought over on HB Superdave told someone he fixes that with a tap??? While were on the subject, how do I know if the braided stuff I'm running is fuel compatable, after that one post saying most were not, I've been wondering ever sense.
 

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Not sure on the ntp threads, never had a problem with that or maybe I never noticed. I have used sweet performance braided line (rubber) for fuel for years with out any trouble. Now I am going to have to go look at my fittings ntp:))eek:))
 

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In places where it shows, I sometimes use a carefully cut piece of SS tubing slipped over the threaded part of the NPT part of the AN fitting. I have found that there is usually at least 1/4 turn of adjustment between where the fitting will seal and where it won't turn any more without risking cracking something. You want to cut the tubing off at the right length so that the AN fitting snugs the tubing down (so it won't rattle) and is tight enough to seal. I use a cut-off band saw to get the angle as square as possible. If it needs to be trimmed, I use the milling machine to trim it, but a lathe would work just as well.

Depending on where the fitting goes, you may also be able to use the "hog the threads out" technique. I only do that if I can clean out the shavings on the back side after using the tap. If there is room, a SS washer looks nice under the hex part of the fitting. Just be careful you don't go too deep!
 

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I don't know why, but AN fittings always seemed to be bigger than their brass counterparts. Maybe SD can chime in with the reason why this is so. I never had the correct drawing standards to know for sure, but I assume this is why.

But I can tell you that I ALWAYS tap the pipe thread deeper by a turn/turn and a half or so on anything I used, machined, or put together that was destined to have an AN fitting installed.

I hated it just like you do.


Brian
 

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Hard lessions to learn for sure.

I have found that there is usually at least 1/4 turn of adjustment between where the fitting will seal and where it won't turn any more without risking cracking something.
 

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Discussion Starter #6
You'll prolly all laugph but I didn't realize taps got wider as they went, other than the inital, really obvious taper. I'll go give her a shot.
 

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You'll prolly all laugph but I didn't realize taps got wider as they went, other than the inital, really obvious taper. I'll go give her a shot.

It's all good.

It is real easy to go from too shallow to too deep in a hurry.

Try a half turn at a time until you get where you want to be.

Brian
 

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Also auto's (especially transmissions) sometimes have a "straight pipe" thread, which has only a small degree of taper compared to a "taper pipe thread". I have no idea why this is , but it is what it is.

So just be careful.

Brian
 

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Umm ...anyway to take it off the fitting instead? Long story short I don't think the tap deal is an option here.

Why?

You have plenty of room

Dont be scared



Brian
 

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"Take it off the fitting"

If you are suggesting shortening the fitting, that won't work anyway. Won't do you any good.
 

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Where the hell are you at dude?

Bring that thing by my shop, I will fix it for you in ten minutes.
 

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Discussion Starter #13 (Edited)
O.K I'll give it a shot(I thought I had that tap but I don't), I hope lowes is open on thanksgiving.lol It's hard to see in the photo.... but the hole that you are lookin at(nearest in the photo) isn't lined up with the ....hole in the front of the fitting. Hopefully I dont need to go past that. I hope that made some sense.. Thanks for the help BTW.
 

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O.K I'll give it a shot, I hope lowes is open on thanksgiving.lol It's hard to see in the photo.... but the hole that you are lookin at isn't lined up with the ....hole in the front of the fitting. Hopefully I dont need to go past that. Thanks for the help BTW.
You're welcome.

So what? Just run a drill thru the hole.

Looks like you have plenty of material all around the port opening.

I'll be at the shop Friday too.

Brian
 

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If there is any "dead spot" in the bottom of the hole where there aren't any threads, you are golden. If there are threads all the way to the bottom(doubtful), then you just need to use a shortened(or a short projection) pipe tap.

Either way, this is so easy of a fix, I am telling you, it is hardly even a blip on the pain-in-the-ass scale.

Brian
 

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I dunno, I don't really consider myself anal, but I'm not diggin how all of my fittings are sticking way out of everything on the npt side. I thought over on HB Superdave told someone he fixes that with a tap??? While were on the subject, how do I know if the braided stuff I'm running is fuel compatable, after that one post saying most were not, I've been wondering ever sense.
Most all the hose the reputable fitting makers use either comes from Parker or Aeroquip. The only hose I know of that people have had problems with is imported.

XRP (the fitting I sell) uses a mixture of the above (currently using Aeroquip). There should be no issues with fuel with Parker or Aeroquip hose.

There is only one way to get less thread extended and that is to tap the part deeper on NPT threads. Straight threads are not an issue as they seal with gaskets or o-rings anyway.
 

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Discussion Starter #17
Thanks Mike and everyone. Fwiw the fitting in question is a russel(sp?) Not all of my fittings stick out this badly, I'm glad I posted this thread because I did learn something.
 

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Rexon, that Parker hose is not what it used to be.
In a nut shell an NPT fitting should screw in 2 1/2 turns and be hand tight.

I donno what kind of pump that is but from looking at that port I know what kind it isn't.
 

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Also auto's (especially transmissions) sometimes have a "straight pipe" thread, which has only a small degree of taper compared to a "taper pipe thread". I have no idea why this is , but it is what it is.

So just be careful.

Brian
the NPSM threads have zero tapper. I've had great fun leaning all the different thread forms. I just happen to have a pile of GM trans fittings (powerglides do take 1/8" NPT).

 
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