Power steering leak/question
 

I'm about ready to burn this darn thing to the ground!!!! I've had a persistent power steering leak. I thought I had it fixed, but noooooo.

The truck has an MII style front suspension with a power rack (obviously). I have installed fittings in the supply and return, to allow the use of -6 lines. I cannot get the pressure side to seal! I took it out yesterday and the leak was more like a flow. I left a oil slick everywhere.

I'm thinking of just going to a manual rack. Has anybody done this? How difficult is it to drive one of these trucks without P/S? I'm open to suggestions and questions as far as the power steering leak goes.

Thanks!!!

Re: Power steering leak/question
 

Have you figured out exactly where the leak is in the line? Is it fitting to fitting, fitting to hard line or fitting to hose?

Re: Power steering leak/question
 

Studying a bit shows that AN style fittings are a bit picky about what hoses you connect them to and that actual aircraft fittings and hoses don't match up with automotive AN fittings that well in some cases.
https://www.pegasusautoracing.com/do...ocID=TECH00096

https://www.speedingparts.com/i/guid...ight-size.html

https://www.dragstuff.com/techarticl...nce-Chart.html

Re: Power steering leak/question
 

I installed PTFE fittings the other day, they seem to be working fine

Re: Power steering leak/question
 

Posted via Mobile Device
I struggled with AN leaking on my Bronco and finally went to local industrial, heavy equipment hose maker (bunches in Tulsa) and had em make SS PTFE lined. Had em make lines for my 51.
I’ll never go back!

Re: Power steering leak/question
 

i had a hydraulic system on a nissan that leaked like a puppy and went to the local parker store. they made end to end hoses and even refilled my accumulators. it wasnt cheap but they never leaked again

Re: Power steering leak/question
 

I believe and am almost positive, it's the fitting to the rack.

Re: Power steering leak/question
 

if you could take the connection apart and post a few pics that may help us figure it out. some had a fitting with a teflon sealing ring and they are finicky about any stress on the line, it has to be kept stress free in an inline configuration.
anyway, don't give up yet, snap a few pics before and after the hose connection "take apart" and post them up. sometimes it helps to thoroughly clean the area with brake cleaner to get any oily residue off, then you can see exactly where the leak starts from and go from there on getting a seal on that spot. it may be a cracked fitting or a set up that needs a swivel where there currently isn't one so the fitting get stressed as the engine moves slightly nder torque etc.

Re: Power steering leak/question
 

i like you Ricky chased that damm high pressure leaks for weeks.
I have found like posted above the AN fitting (most cheap ones) don't seal like they should. AND i have had what looked like NPT actually be a o-ring fitting missing o-ring in the past. My new motto on high pressure stuff for power steering and fuel is the absolute least amount of fittings and use good ones.

On you note of going manual. We drove this truck for 3 years with manual steering. once I went to PS I will never go back. :)


Holst

Re: Power steering leak/question
 

Steering effort depends on your rack and steering wheel diameter, tire width and offset.

Factory '50s truck is probably 4-5 turns lock to lock with a big diameter wheel and skinny tires.
Mustang II power rack is 2-3 turns lock to lock, you may have a smaller wheel and wider tires and some offset.

It will probably steer fine without ps rolling at speed, but be a bear to park. There is technique to parking manual steering that helps, slow roll while you crank the wheel.

Re: Power steering leak/question
 

Ok, here's my take on this having worked in the hydraulic fitting business. I do not like the term "AN" as it very generic. In my experience and in MY mind, AN actually refers back to Army/Naval drawings which covered a lot of different styles and type of fittings. In addition a lot of these were used on aircraft and the tolerances were a lot tighter and had class 3 threads versus a commercial grade class 2 thread. I do not think these fittings termed this way in the current automotive market are manufactured to these standards and I assume they are stating AN=37 degree. Then there are also 45 degree (not the inverted 45 deg used on brake lines) and 37 degree angle seats used. The 45 deg is used for air brake applications and the 37 is for hydraulic applications. Need to also note these are designed to seal using one small ring of surface area on the seat - not the entire face and seat. This means both fittings must be made to the same tolerances, preferably to SAE J516. If they aren't you can be chasing your tail. Also need to make sure you're following proper torquing when installing. In addition keep an eye out for inch and metric threads nowadays. If some of the ports are straight thread o-ring on the rack make sure you have those torqued correctly and have the the correct o-rings. My $.02 - not sure if it helps or not.

Re: Power steering leak/question
 

I'd say fix the leak and keep power steering.
If you can find where the actual leak is, take the hose off, snap a pic of the connection point at the rack and pump and then take the hose to a hydraulic shop and have one made for you. Ensure there is ability for the hose to swivel on at least one end and that there is sufficient hose length to allow for engine flex. Personally I am not a big fan of the aluminum fittings as they look cool but threads bind fittings go out of round when tightened down and the threads tend to fall. That's just me though.
A fitting that looks like not but has an O ring may be an ORB fitting. O ring boss.

Re: Power steering leak/question
 

57 tailgater wrote out what my thoughts were after I did some searching the other night but with an educated answer. Not all -6 or AN style fittings are created equal. You may have a 37 degree fitting connected to a 45 degree fitting and not sealing as it should.

I'd take the line off from pump to rack and set it on the bench and check the fittings closely. Still I believe that you would be better off either to order a complete hose designed for the application or go to a hydraulic shop and have one made that had the correct ends on it.

Re: Power steering leak/question
 

Yup, don't let it beat you. It's just a hose and fittings. You got this, just take it off, check for cracks on the sealing surfaces or distortion and grooves, out of round fittings, galled threads, torn seals, etc. If there appears to be no reason for a leak, take it to a hydraulic shop and see if they can check it visually or just get a new one made with matching fittings

Re: Power steering leak/question
 

Thanks for all the tips. I purchased these, https://www.summitracing.com/parts/BRG-925120 and hopefully, this might end the issue. I have plenty of hose to allow engine movement and I know it's the fitting from the high pressure side. As I said, I will give these a go and see what happens.

Re: Power steering leak/question
 

what fitting do you have going into the rack? thats where the leak is, correct? so the new fitting is gonna sfrew into the rack and seal with the O ring? maybe check the housing where the O ring is gonna seal and make sure it is nice and flat/smooth so the O ring doesn't get cut.

Re: Power steering leak/question
 

After looking for a -6 fitting that will work with Matt 50's fuel filter it came to mind that you didn't by chance use a compression fitting on that pressure line? They are low pressure only and won't handle power steering or brake pressure.

Re: Power steering leak/question
 

Nope, no compressions fittings at all in the power steering loop!

Re: Power steering leak/question
 

good to hear

Re: Power steering leak/question
 

If it is leaking at a specific -6 connection I would take that connection apart and examine the male and female parts to see if the angle of the contact area was the same. I'm assuming that you bought the fittngs from a reliable automotive fitting source but if you happened to get mix and match fittings they can screw together but have different tapers depending on the original application.

I've run into issues with bad flares on tubing when I used my 50 something year old flare tool that didn't always do a perfect flare so you may want to check flares on any flared tubing.

Best thing is probably run it down to the quarter car wash, wash it all off and then check to figure out exactly where the leak is when it is clean. Power steering fluid tends to spread out all over stuff when you have a leak and it is hard to figure out exactly where the leak is.

Re: Power steering leak/question
 

First, I have to exchange the fittings I just bought. They are listed as fitting the Mustang rack, well, they don't!! I'll be ringing up Summit later for an exchange. The power steering hoses and couplers were purchased from PSC. I'm pretty positive it was leaking from the high pressure side of the rack where the fitting screws into the rack itself.

Re: Power steering leak/question
 

if you know what the rack was originally from you could look up a hose for that and see what type of fitting is required at the rack end of things. otherwise maybe somebody like heidts could help you out with the fitting size and thread you need?
maybe this has the fitting info you need?
https://www.google.com/url?sa=t&sour...3q-2woEVKb6dK0

Re: Power steering leak/question
 

https://leepowersteering.com/product...9-16-inch-to-6

https://www.cjponyparts.com/russell-...xoC90sQAvD_BwE

I guess the other thing you could do is stop by a parts place and actually lay hands on a pressure line from a mustang or thunderbird. once you see one that looks like it fits you could check the specs for what fitting is on the rack end, then go through the fittings selection at the store, or the parts guy could look up a fitting that fits the rack and the hose you currently have.

Re: Power steering leak/question
 

Sometimes the rack supplied with the MII kit has been modified at the hose connections as well. Do you know the brand of the MII kit under your project?

Re: Power steering leak/question
 

As I recall, Restoration Rods has a pretty good selection of in stock -AN fittings. You might be able to find something there.