TheSamba.com :: View topic - AN-6 vs AN-8

Fri Aug 05, 2016 2:47 pm

Hi Everyone, I have a question I can't find an answer to.

I'm getting ready to prep the setup for the remote oil filter. I ordered AN-8 to 3/8 fittings. Then I noticed a lot of images of remote filters with AN-6 lines. I figured the more flow I can get in/out of the filter the better by going to AN-8.

Is there any reason to run such a small line to and from the filter? Is there any reason I shouldn't run AN-8?

Fri Aug 05, 2016 2:57 pm

I've only seen AN8 used for oil. AN6 is too small.

Fri Aug 05, 2016 2:58 pm

That was my thought but wanted to be sure. Thanks Glenn

Fri Aug 05, 2016 3:03 pm

AN8 for oil lines, AN6 for fuel lines

Fri Aug 05, 2016 3:25 pm

That's what I have but I seen these and to me they look like 6s and I was thinking what if this is one of those "Oh you need some special thingy to run 8s" :lol:

Fri Aug 05, 2016 4:09 pm

Fri Aug 05, 2016 4:25 pm

Teflon hose is smaller in the outside then standard steel braided rubber hose.

Fri Aug 05, 2016 4:37 pm

AN6 will match the too small passages in many filteradapters and pumpcovers though.
I bore them out if necessary.

Fri Aug 05, 2016 5:01 pm

The whole "AN" system goes by 16ths of an inch... Thus, AN-8=1/2". But, I'll bet no one here has a filter mount, case, or cooler tapped for any larger than 3/8" pipe thread.

Fri Aug 05, 2016 5:17 pm

NPT is measured differently, so 3/8" NPT is closer to AN 8 than 1/2" NPT. Just compare the 2 in your hand, it's a big difference. A 1/2" NPT matches a -10 much better.

Fri Aug 05, 2016 5:40 pm

Being used to the rubber hoses, looking at those Teflon hoses I could have sworn I was looking at -6 hoses. :oops:

Fri Aug 05, 2016 6:20 pm

I use AN-10 for the oil hoses. Regardless if you use AN-8 or AN-10 make sure you do not use restrictive brass fittings. If you do you should port the restrictive fittings first. Better yet just buy some quality XRP fittings that flow well from the get go and are not restrictive. You still may need to clean up casting flash on the oil cooler mount.

Fri Aug 05, 2016 7:19 pm

roachdub58 wrote: NPT is measured differently, so 3/8" NPT is closer to AN 8 than 1/2" NPT. Just compare the 2 in your hand, it's a big difference. A 1/2" NPT matches a -10 much better.

Pipe is always measure by the bore(except above 12 inch). Ultimately, your plumbing will have no better flow than through the smallest orifice through which it has to flow... In this case, 3/8". In my mind's eye(cause I never measured the damned thing), I don't imagine any of the oil passages of the case being any larger than that either.

Fri Aug 05, 2016 7:53 pm

My main galley measured 11mm.
So my pump cover and the an fittings and such are sized to have no less than 11mm minimum id restriction. So that meant an-10 fittings. The hose is huge looking but the fittings id are just barely larger than 11mm.

Fri Aug 05, 2016 8:03 pm

74 Thing wrote: I use AN-10 for the oil hoses. Regardless if you use AN-8 or AN-10 make sure you do not use restrictive brass fittings. If you do you should port the restrictive fittings first. Better yet just buy some quality XRP fittings that flow well from the get go and are not restrictive. You still may need to clean up casting flash on the oil cooler mount.

Nope, no brass fittings. I use either Russell or Earl's fittings only.

Fri Aug 05, 2016 10:11 pm

I started using AN10 hose and fittings.I also use filter housings with 1/2 npt openings. I have always used AN 8 before but i have all 1/2 " hardware available now so i went AN10.

Sat Aug 06, 2016 6:19 am

74 Thing wrote: I use AN-10 for the oil hoses. Regardless if you use AN-8 or AN-10 make sure you do not use restrictive brass fittings. If you do you should port the restrictive fittings first. Better yet just buy some quality XRP fittings that flow well from the get go and are not restrictive. You still may need to clean up casting flash on the oil cooler mount.

I'm always praising XRP. I've sold thousands of fittings and made/crimped tons of a/c, Teflon brake, oil, hydraulic, and fuel hoses. The quality and consistency are some of the best. Not all fittings are the same. If you were to order a standard XRP -8 NPT to AN adapter fitting, it will be 3/8" NPT. The hole machined through is one size. AN seals on the face, so the size of the hole can vary between manufacturers. If flow is your concern, don't get hardware store fittings or Chinese AN that may have a smaller hole or step machined into it.

Sat Aug 06, 2016 9:59 am

Glenn wrote: -8

I like this combo cause you get more room to not hit header pipes, but still maintain 3/8 id.

Where did you get this hose kit Glenn?

Sat Aug 06, 2016 10:00 am

jpaull wrote: Where did you get this hose kit Glenn?
Gene Berg.

Sat Aug 06, 2016 12:12 pm

roachdub58 wrote: 74 Thing wrote: I use AN-10 for the oil hoses. Regardless if you use AN-8 or AN-10 make sure you do not use restrictive brass fittings. If you do you should port the restrictive fittings first. Better yet just buy some quality XRP fittings that flow well from the get go and are not restrictive. You still may need to clean up casting flash on the oil cooler mount.

I'm always praising XRP. I've sold thousands of fittings and made/crimped tons of a/c, Teflon brake, oil, hydraulic, and fuel hoses. The quality and consistency are some of the best. Not all fittings are the same. If you were to order a standard XRP -8 NPT to AN adapter fitting, it will be 3/8" NPT. The hole machined through is one size. AN seals on the face, so the size of the hole can vary between manufacturers. If flow is your concern, don't get hardware store fittings or Chinese AN that may have a smaller hole or step machined into it.

Is my perception wrong but isn't the hole in fitting and inside diameter of tube supposed to be the same for "-X" AN fitting you get..

Though AN stood for "ARMY-NAVY" (AN) standard so military machinery all have same fittings so there would never be a supply problem if a replacement fitting was needed.... Some place a few years back the was a military document the specified any AN fitting to be used on military machines....

Also as you increase size of fitting the area of inside almost doubles so a a AN-8 will flow almost double a AN-6 will flow...

Just for giggles...

http://www.diamondfasteners.com/Military-Fasteners/fittings/an-fittings

Dale