NPT to steel line - Hey I can edit subject lines in place, I didn't know that! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

davepl · 04-26-2018, 11:20 AM

I'm looking at an EFI pump module that uses an in-tank Walbro pump. It then has 1/4" NPT supply and return fittings.

I would like to use TWO factory fuel lines, one for the pressure side and then the duplicate right along side it as the return.

What's my shortest path to get from 1/4" NPT to braided flex and then to steel line? In other words, how to connect braided hoses to a steel fuel line.

I was thinking:

NTP -> NTP-6AN -> 6AN union -> tube nut on line

It's connecting to the 3/8" hard stainless fuel line that I'm most concerned about. I have the hydraulic flaring tool AND I ever have the 37 degree flaring pieces, so in theory I should have what I need.

I'm trying to avoid ANY rubber in the EFI system, so that's why I'm trying to go NPT to AN to braided line to hard line.

**HO455** · 04-26-2018, 11:40 AM

The most direct way would be to go to a hydraulic shop and have them make you two hoses with the fittings you want on the ends. These guys have done some for me.

http://www.ofsco.net

davepl · 04-26-2018, 11:43 AM

Yeah, but that doesn't help me connect it to the hard line. That's the hard part. Flaring in place with a 37 degree tool with a tube nut and so on... that's the part I have no idea about.

This guy is doing it I think:
https://www.youtube.com/watch?v=46hF...projectgattago

**Rickysnickers** · 04-26-2018, 11:59 AM

Will any of these work? https://www.holley.com/brands/earls/...o_an_adapters/

davepl · 04-26-2018, 12:00 PM

Here's what I wound up ordering:

TanksInc Pump module with 1/4" NPT inlet and outlet
1/4" NPT to -6AN male
-6AN hose end
-6AN hose
-6AN hose end
-6AN male to male union
-6AN tube nut and sleeve
3/8" stainless hard line

**HO455** · 04-26-2018, 12:01 PM

I would do double flares on the hard lines with male fittings before installing them. Then use a female inverted flare fitting crimped to the hose. Like the one shown. I believe you can get them in a 45* or a 90* versions too.

Benjamin · 04-26-2018, 12:47 PM

I ran into a similar problem recently. subscribed.

davepl · 04-26-2018, 01:08 PM

HO455, how do you put a male end on a hose? I was going to use the standard single-flare with tube nut and sleve (where you can't double flare)

**HO455** · 04-26-2018, 01:27 PM

I am assuming you mean male 45* inverted flare? Looks like these.

binford · 04-26-2018, 07:48 PM

Are you running a TBI?

Earl's makes NPT to AN fittings
That will work with the flex hose.
Use some type of PTFE liner as it will last forever

Double flares connection are a pain and I find I have to make a few practice ones first on some scrap tubing.
There is a local shop that has a machine he uses for making SS brake lines. Perfect flare everytime

Dorman make a TBI kit, that is steel and about 20" long with flared connection on both ends

MARKDTN · 04-27-2018, 07:54 AM

Go to a hydraulic shop and you can get hydraulic fittings for steel lines. Don't use hardware store brass compression gas line fittings, they were not made for the high pressure.

https://www.discounthydraulichose.co...tings_s/51.htm

Something like these.

binford · 04-27-2018, 09:25 AM

Thanks for the link, I like those fittings.

davepl · 04-27-2018, 11:00 AM

Unfortunately it's an 18 foot steel line that would be pretty tough to take out of the car and haul anywhere! I kinda have to do this one in the car, at least for the existing line.

I've always wondered about brass fittings. The factory uses brass fittings in the brake system. That doesn't mean Home Depot is your hot ticket for factory fittings, but I can't think of any downside to using a potable water fitting if it's NPT. No idea about compression. But all my compression stuff is 37 degree AN anyway.

binford · 04-27-2018, 12:28 PM

Dave check out the link Mark posted.
I've used these type of connectors before.
The advantage is less parts used and no flare needed
I've used brass fittings before, but on my current build I will be using theses

https://www.discounthydraulichose.co...7208-06-06.htm

https://www.discounthydraulichose.co...7205-06-02.htm

**HO455** · 04-27-2018, 04:04 PM

I used Aeroquip compression fittings to replace the little rubber hose in the middle of the fuel line on my Burban. I really didn't want to try and flare the ends in place. Worked well.

sprint_9 · 04-27-2018, 11:10 PM

This is the type of fitting setup you are after I believe.

Also make sure your AN hose is more than a braided rubber hose. I used PTFE hose.

72Cheyenne454 · 04-27-2018, 11:20 PM

I've used Swagelok fittings before. Take a look at their website...

https://www.swagelok.com/en/product

04-26-2018, 11:20 AM	#1
davepl Registered User Join Date: Aug 2006 Location: Redmond, WA Posts: 6,332	NPT to steel line - Hey I can edit subject lines in place, I didn't know that! I'm looking at an EFI pump module that uses an in-tank Walbro pump. It then has 1/4" NPT supply and return fittings. I would like to use TWO factory fuel lines, one for the pressure side and then the duplicate right along side it as the return. What's my shortest path to get from 1/4" NPT to braided flex and then to steel line? In other words, how to connect braided hoses to a steel fuel line. I was thinking: NTP -> NTP-6AN -> 6AN union -> tube nut on line It's connecting to the 3/8" hard stainless fuel line that I'm most concerned about. I have the hydraulic flaring tool AND I ever have the 37 degree flaring pieces, so in theory I should have what I need. I'm trying to avoid ANY rubber in the EFI system, so that's why I'm trying to go NPT to AN to braided line to hard line. __________________ 1970 GMC Sierra Grande Custom Camper - Built, not Bought 1969 Pontiac 2+2 427/390 4-speed Coupe 1969 Pontiac 2+2 427/390 4-speed Convertible

04-26-2018, 11:40 AM	#2
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 10,804	Re: NPT to steel line The most direct way would be to go to a hydraulic shop and have them make you two hoses with the fittings you want on the ends. These guys have done some for me. http://www.ofsco.net __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377

04-26-2018, 11:43 AM	#3
davepl Registered User Join Date: Aug 2006 Location: Redmond, WA Posts: 6,332	Re: NPT to steel line Yeah, but that doesn't help me connect it to the hard line. That's the hard part. Flaring in place with a 37 degree tool with a tube nut and so on... that's the part I have no idea about. This guy is doing it I think: https://www.youtube.com/watch?v=46hF...projectgattago __________________ 1970 GMC Sierra Grande Custom Camper - Built, not Bought 1969 Pontiac 2+2 427/390 4-speed Coupe 1969 Pontiac 2+2 427/390 4-speed Convertible

04-26-2018, 11:59 AM	#4
Rickysnickers Senior Member Join Date: Oct 2014 Location: Eagle, ID Posts: 2,937	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Will any of these work? https://www.holley.com/brands/earls/...o_an_adapters/

04-26-2018, 12:00 PM	#5
davepl Registered User Join Date: Aug 2006 Location: Redmond, WA Posts: 6,332	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Here's what I wound up ordering: TanksInc Pump module with 1/4" NPT inlet and outlet 1/4" NPT to -6AN male -6AN hose end -6AN hose -6AN hose end -6AN male to male union -6AN tube nut and sleeve 3/8" stainless hard line __________________ 1970 GMC Sierra Grande Custom Camper - Built, not Bought 1969 Pontiac 2+2 427/390 4-speed Coupe 1969 Pontiac 2+2 427/390 4-speed Convertible

04-26-2018, 12:01 PM	#6
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 10,804	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! I would do double flares on the hard lines with male fittings before installing them. Then use a female inverted flare fitting crimped to the hose. Like the one shown. I believe you can get them in a 45* or a 90* versions too. Attached Images __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377

04-26-2018, 12:47 PM	#7
Benjamin Registered User Join Date: Jul 2012 Location: New Orleans, LA Posts: 184	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! I ran into a similar problem recently. subscribed. __________________ 1972 K10, 350/SM465/NP205, 4 inch lift, 35x12.50s on 15x10 wheels 1976 K20 crew cab, 350/Ranger/SM465/NP205

04-26-2018, 01:08 PM	#8
davepl Registered User Join Date: Aug 2006 Location: Redmond, WA Posts: 6,332	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! HO455, how do you put a male end on a hose? I was going to use the standard single-flare with tube nut and sleve (where you can't double flare) __________________ 1970 GMC Sierra Grande Custom Camper - Built, not Bought 1969 Pontiac 2+2 427/390 4-speed Coupe 1969 Pontiac 2+2 427/390 4-speed Convertible

04-26-2018, 01:27 PM	#9
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 10,804	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! I am assuming you mean male 45* inverted flare? Looks like these. Attached Images __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377

04-26-2018, 07:48 PM	#10
binford Registered User Join Date: Aug 2004 Location: Sacramento Ca Posts: 126	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Are you running a TBI? Earl's makes NPT to AN fittings That will work with the flex hose. Use some type of PTFE liner as it will last forever Double flares connection are a pain and I find I have to make a few practice ones first on some scrap tubing. There is a local shop that has a machine he uses for making SS brake lines. Perfect flare everytime Dorman make a TBI kit, that is steel and about 20" long with flared connection on both ends

04-27-2018, 07:54 AM	#11
MARKDTN Registered User Join Date: Jan 2011 Location: Chattanooga, TN Posts: 2,131	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Go to a hydraulic shop and you can get hydraulic fittings for steel lines. Don't use hardware store brass compression gas line fittings, they were not made for the high pressure. https://www.discounthydraulichose.co...tings_s/51.htm Something like these. __________________ '83 K20-TPI '73 C10 '79 C10-ex-diesel(SOLD) '07 Tahoe(Son driving) '14 Suburban-DD '71 C10-current project

04-27-2018, 09:25 AM	#12
binford Registered User Join Date: Aug 2004 Location: Sacramento Ca Posts: 126	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Thanks for the link, I like those fittings.

04-27-2018, 11:00 AM	#13
davepl Registered User Join Date: Aug 2006 Location: Redmond, WA Posts: 6,332	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Unfortunately it's an 18 foot steel line that would be pretty tough to take out of the car and haul anywhere! I kinda have to do this one in the car, at least for the existing line. I've always wondered about brass fittings. The factory uses brass fittings in the brake system. That doesn't mean Home Depot is your hot ticket for factory fittings, but I can't think of any downside to using a potable water fitting if it's NPT. No idea about compression. But all my compression stuff is 37 degree AN anyway. __________________ 1970 GMC Sierra Grande Custom Camper - Built, not Bought 1969 Pontiac 2+2 427/390 4-speed Coupe 1969 Pontiac 2+2 427/390 4-speed Convertible

04-27-2018, 12:28 PM	#14
binford Registered User Join Date: Aug 2004 Location: Sacramento Ca Posts: 126	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! Dave check out the link Mark posted. I've used these type of connectors before. The advantage is less parts used and no flare needed I've used brass fittings before, but on my current build I will be using theses https://www.discounthydraulichose.co...7208-06-06.htm https://www.discounthydraulichose.co...7205-06-02.htm Last edited by binford; 04-27-2018 at 12:40 PM.

04-27-2018, 04:04 PM	#15
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 10,804	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! I used Aeroquip compression fittings to replace the little rubber hose in the middle of the fuel line on my Burban. I really didn't want to try and flare the ends in place. Worked well. Attached Images __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377



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04-27-2018, 11:10 PM	#16
sprint_9 Registered User Join Date: Nov 2012 Location: 9 Posts: 862	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! This is the type of fitting setup you are after I believe. Also make sure your AN hose is more than a braided rubber hose. I used PTFE hose. Attached Images

04-27-2018, 11:20 PM	#17
72Cheyenne454 Registered User Join Date: Apr 2007 Location: San Diego Posts: 453	Re: NPT to steel line - Hey I can edit subject lines in place, I didn't know that! I've used Swagelok fittings before. Take a look at their website... https://www.swagelok.com/en/product

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