April 18, 2019, 02:29:44 PM

Author Topic: Adapting factory PS hardlines to AN line  (Read 675 times)

Offline shainiac

Adapting factory PS hardlines to AN line
« on: July 25, 2018, 10:16:12 AM »
*Full disclosure, I havent been able to test the methods below on a running car. Use at your own risk.*

Ive had bad luck getting off-the-shelf AN fittings to adapt to the stock FC power steering high pressure feed. The biggest issue is that the threads start below the surface and standard AN-metric fittings dont have enough thread engagement and eventually strip out. So, I bought a set of used power steering lines (threw my originals away a long time ago  :banghead:)

First things first, the OEM FC high pressure hose is two pieces, connected by a inverted flare tube nut.
The tube nut thread pitch is M12x1.0. This is an oddball size. I was unable to track down a fitting to adapt from M12x1.0 inverted flare to 6AN.
The second thing worth noting the tubing isnt metric, its copper tubing. Lucky for me, I have a box of old Swagelok and Parker compression fittings in SAE sizes. I had to use 3 fittings to make it work, but I successfully adapted from tube to 6AN right at the line.
These hydraulic fittings are very easy to use and rated to well over the working pressure of copper tubing.
You could accomplish the same for about $20. See the McMaster part in the photos below. The beauty of Swagelok/Parker compression fittings, you just cut and clean the tube, deburr, and tighten the nut. Its very easy and quick. Also, the fittings are reusable if you have spare ferrules.

My concern, The PTFE-line 6AN power steering hose Im using is much stiffer than the copper line. There isnt really a way to secure the OEM tubing to the chassis and isolate it from any tension from the PS hose. My question: If the OEM line is OD copper tubing, would it be acceptable to use 4AN PTFE braided hose? It is much less rigid than the 6AN. FWIW, I already have plenty of both on hand, so its not a cost issue.


OEM Feed line


Nut size


Thread pitch (compared to an M6x1.0 bolt


Factory inverted flare fitting on hard line


Factory hard line 0.25 OD


My hodgepodge of Parker/Swagelok fittings. Also, the cut, cleaned, and deburred tubing.


What you need: (plus a 6AN > NPT fitting)


Fitting installed


Compression ferule should look like this


Installed (needs tweaking to end up were you want it pointed)

'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

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Offline jwvand02

Re: Adapting factory PS hardlines to AN line
« Reply #1 on: July 25, 2018, 01:23:55 PM »
So there's really no alteration to the piece of the line closest to the rack - the point is more that we can split it at that flare nut to work on the pump side, right?

This seems straightforward enough that it might finally convince me to just do hydraulic PS if I can't make an electric system work.

Offline shainiac

Re: Adapting factory PS hardlines to AN line
« Reply #2 on: July 25, 2018, 01:56:50 PM »
Correct.
You could also easily break the connection at the compression fitting. They're designed to be tightened/loosened a few times without issues. You could just as easily cut the lower power steering line and omit the flare nut. I may end up doing that since I have to avoid a turbo and other stuff in the way.
'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

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Offline freeskier7791

Re: Adapting factory PS hardlines to AN line
« Reply #3 on: July 26, 2018, 04:16:13 PM »
Whatever tubing or hose you use should be rated to at least 6000 psi so you don't burst a line

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Offline DDv8

Re: Adapting factory PS hardlines to AN line
« Reply #4 on: July 26, 2018, 09:32:07 PM »
I was retasking the ps cool loop-return and it was not copper  (steel tubing) .  So I took a magnet to check the pressure banjo lines and they are steel also.

freeskier  fsm 10b-9 says 1138 psi hot is standard pressure for FC pump http://www.norotors.com/pdfs/s4manuals/10b_POWER_STEERING_SYSTEM.pdf   6000psi line may be overkill. 3000 is more flexible

Pressure and return lines on the FC rack are 8mm tube ~ -6  going with -4 will kill volume at the rack
the small pressure line is 6mm ~ -4 and is about 43 psi and very little volume   fsm see above link

I just rebuilt my ps pump (new front bearing, seal and O rings) The 3 line pump (vane type) has 2 pressure sections hence the 1138 and 43 psi pressure lines and relief spring I'll assume is around 1200psi haven't tested.
just an fyi for anyone buying a seal kit, most likely it is for the 2 hole pump.  The body gasket (steel/rubber) is correct but I had to supply 3 metric O rings and make the reservoir O ring ( cut down and glued larger one) Also discovered the front bearing was bad do to the seal leak which is behind the bearing (washes grease from bearing).

The job isn't hard just need to be scrupulously clean (cleaned out side in parts washer (sealed ports) and then brake clean before disassembly. also need small press to remove/install   bearing+shaft from housing and bearing from shaft.

DD

86fc old school 327, T5, converting to 8.8 tbird

Offline freeskier7791

Re: Adapting factory PS hardlines to AN line
« Reply #5 on: July 26, 2018, 10:43:04 PM »
I would agree 3000 psi line is adequete.

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Offline shainiac

Re: Adapting factory PS hardlines to AN line
« Reply #6 on: July 27, 2018, 08:05:39 AM »
I was retasking the ps cool loop-return and it was not copper  (steel tubing) .  So I took a magnet to check the pressure banjo lines and they are steel also.
 

The tube I cut was definitely copper. Very flexible, non-magnetic, and looked like copper.


Pressure and return lines on the FC rack are 8mm tube ~ -6  going with -4 will kill volume at the rack
the small pressure line is 6mm ~ -4 and is about 43 psi and very little volume   fsm see above link
DD

So the lines I bought used on eBay, there was one small and one large. I presumed these were one high pressure and one return but I think they are both high pressure lines from the 3-port rack. The smaller line (1/4) that I spliced was for the high-speed circuit which is less flow. I will measure the other line tonight which is much larger. Hopefully it is 3/8 and steel. If that is the case, I will modify my first post so no one goes around using the tiny cooler line.

'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

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Offline DDv8

Re: Adapting factory PS hardlines to AN line
« Reply #7 on: July 27, 2018, 08:48:28 PM »
Good picture   both banjos are high pressure, the cooler/return line is the 8mm soft hose IFF connection without the banjo, it is low pressure to the loop and returns to the ps reservoir. 

your copper line is strange s5?   The 4 sets of s4 banjos I have are steel.

DD
86fc old school 327, T5, converting to 8.8 tbird

Offline shainiac

Re: Adapting factory PS hardlines to AN line
« Reply #8 on: July 28, 2018, 08:49:47 AM »
Good picture   both banjos are high pressure, the cooler/return line is the 8mm soft hose IFF connection without the banjo, it is low pressure to the loop and returns to the ps reservoir. 

your copper line is strange s5?   The 4 sets of s4 banjos I have are steel.

DD

So, the lines (both) are copper-lined steel tubing.
I couldn't see the copper at the flares, but only when I cut the lines.

See the color:

'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

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Offline shainiac

Re: Adapting factory PS hardlines to AN line
« Reply #9 on: July 28, 2018, 09:29:54 PM »
Here's V2

I was able to use the larger PS line and am much happier with the result.
The 10mm tubing is also copper-lined steel and pretty tough. I had to bend it to clear my turbo.
I ended up using two of the tubing vises from two different brake flaring kits so I could grip the tubing itself and not stress the tube nut or banjo fitting.
I'd like to add some head shielding but I'm a bit worried that if I do I won't be able to see any leaks at first startup until the fiberglass is saturated and potentially turns into a candle.

10mm OD


M16x1.5 at the tube nut


Adapter from M16 to 6AN


Banjo installed


Line installed

'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

Build Thread      Instagram      Youtube

Offline 346fc3s

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Re: Adapting factory PS hardlines to AN line
« Reply #10 on: August 25, 2018, 07:06:35 PM »
You can find m16x1.5 to -6an adapters that are made for a crush washer on summit for a few dollars.  Then just use your -6an PTFE hose from pump to rack.  I usually have a hose made by the local Napa or hydraulic shop.  The last one I had made cost me $4 for the fitting, $25 for the entire new hose and the rest was history.  Just have to make sure you get the hose made the correct length, as you said, the high pressure stuff is a lot harder to flex. 
'87 Turbo II 5.3/T56
'03 Ram 3500 diesel, tow rig
'04 RX8 track toy
'05 IS300 wagon- waiting for a v8

Offline shainiac

Re: Adapting factory PS hardlines to AN line
« Reply #11 on: August 25, 2018, 07:30:03 PM »
The problem with the AN fitting directly into the rack - there are no threads for the first 1/2" or so of the rack. You end up only getting a couple threads of engagement. I stripped out my first fitting before I noticed that. I think there are people that have had good luck, but I didn't want to risk it with my turbo so close to the fittings. A leak could total the car lol
'88 TII - 13BT, MS3X , EFR 9180 IWG, A2W Intercooled
539whp/407wtq @ 25.5psi

Soon to be Alum 5.3 GenIV LS, Twin EFR 6758s, T56 Magnum, Ronin 8.8" IRS, MS3Pro Ultimate

Build Thread      Instagram      Youtube

Offline 346fc3s

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Re: Adapting factory PS hardlines to AN line
« Reply #12 on: August 26, 2018, 02:31:21 PM »
Agreed, I had good luck with mine but I don't blame you at all.  It would be a silly reason to kill a car. 
'87 Turbo II 5.3/T56
'03 Ram 3500 diesel, tow rig
'04 RX8 track toy
'05 IS300 wagon- waiting for a v8