Power Steering Deep Dive

[Stanglover]

I was thinking about scanning a bunch of information I have, but at this point, I think that as you've had you PS box rebuilt, it is up to the rebuilder to fix it and make sure it is correct. There is simply too much to learn for me or Bentworker  (or others) to explain in a few posts. 

I have no idea what is really the problem that caused your HP hose to burst. Sending the box away again was a good start, one thing at a time.  Unless you want the authentic look, you don't need the long hose, you can use a 72/73 short hose. It's frustrating as hell for sure.

Good luck moving forward.

If you want to look at some sheets from Saginaw Power Steering Gear, then look at https://www.chevelles.com/techref/PowerStrgGear.jpg  ( I hate to go to Chevy stuff, but after all, Saginaw is a GM company!!)

Edit: Ooops, that link didn't work, try entering it in Google. It worked for me earlier.

 

[Bentworker]

There is no harm in resealing your original pump.  I’ve never done one of the Ford pumps, but it can’t be too bad.   There is a good chance the rotor / cam and other goodies inside your original pump in great shape.

As far as Dorman reman stuff goes, I would guess that not all the products that go out the door are perfect.  Sometimes “rebuilt” products are not actually rebuilt very well.
 

I’ll be surprised if anything is found faulty with your steering box.  

 

[kcmash]

I will be surprised if they do too.  But is was under warranty and they were willing to give it another look over and tear i5 down if needed.  Stinks since the weather here today is sunny and 70, perfect for driving it. 
 

I am going to look at the hose and study engineering guidelines for crimp standards for 1500 psi hydraulic hoses.  I noticed the crimp pattern on the blown hose has no annular features, only longitudinal creases, where the Edelman short hose I have has both types of crimp.

The gold chromate is the failed crimp and the grey is the Edelman hose.

kcmash

 

[6DUB606]

I have been in the hydraulics / fluid power industry for many years.  General requirements for all hoses, end fittings & adapters is for a 4 : 1 safety factor - means that if a system is intended to work at 1,500 p.s.i., the " design minimum burst " for all components should be 6,000.  We always static tested hose assemblies to twice the stated working pressure - 3,000 in this case.  The crimp characteristics are from the machine used and should be checked by the manufacturer to meet or exceed  the 4 : 1 criteria.  Some are certainly more reliable than others.  Hose assemblies often act as an unofficial fuse - the $30 hose will fail before you blow a more critical unit such as the pump, cylinder or valve block etc.  If the relief valve doesn't do its job, this is often your clue that it has gone to the point of least resistance.

I am more confident in the styles that have a lateral compression pattern as the forces are spread around the full circumference.  The chromate one is holding on by the depressions parallel to the line of greatest pressure and shock loads can cause the fitting to gradually inch its way off.  Look at the rubber cover of the failed hose - is it still fairly smooth ?  If so, that suggests that it has simply pulled itself apart.  You may get some test specs info from manufacturers so certainly worth the questions.

Keep digging.

PKJ

 

[kcmash]

So I must give kudos to a couple vendors out there.

1) I worked with National Parts Depot on the hose.  Provided photos, and talked about the concerns with the crimp.  They checked inventory and found one they thought looked better than my crimp and are replacing at their cost.  I sent them a few pics of my car, so you may see it in an upcoming catalogue ( yeah right )

2) Marty at Power Steering.com told me they did find a retaining ring out of place that likely caused some of my erratic power assist conditions.  The box will arrive back here tomorrow and he even refunded me some money for my trouble.  I strongly recommend them for good customer service.

Hopefully I can get the steering reassembled this weekend.

kcmash

 

[jpaz]

That’s one sweet ride! Thanks for letting us know about some good customer service.

 

[kcmash]

Ok I need some more help.

Power steering box is back in, and new high pressure hose installed.  I filled the system by adding fluid and cranking, then repeating.  Once the fluid level was stable I pushed the car outside and started it.  I then began slowly turning side to side .

Right was better than left.  Some groaning and not so well assisted steering.  I shut it off and found it was pushing fluid out the  fill tube.  I removed the dipstick to check level and there was foamy/bubbly fluid near the top of the tube.  I started it again and tried cycling left to right figuring it needed to push more excess fluid out, but the assist was getting worse and feeling tighter.

So then I thought I must be letting air get sucked in through the fill tube making it worse.  I replaced the dipstick and tried starting and cycling the steering again with intermittent assist and some really tough spots.  So I shut it down to look for advice.

1) When installing the steering box, the mechanism did get turned some from left to right as I connected the rag joint and drag link.

2) I am unsure if the bleeding procedure I used is correct.  I saw one from Dorman with the rebuilt pump that said to disconnect the return hose when adding fluid until clear, bubble free fluid came out.  I did find a small amount of fluid pooled around the return hose at the box connection, so that could be an air intake source.

Finally, I thought, gee, did I maybe get the hoses switched at the box and sending high pressure in the low side.  I checked all the restoration guides that show the high pressure going in the port closer to the engine, which is how mine is connected.

Any suggestions.

kcmash

 

[Stanglover]

Ok I need some more help.

Power steering box is back in, and new high pressure hose installed.  I filled the system by adding fluid and cranking, then repeating.  Once the fluid level was stable I pushed the car outside and started it.  I then began slowly turning side to side .

Right was better than left.  Some groaning and not so well assisted steering.  I shut it off and found it was pushing fluid out the  fill tube.  I removed the dipstick to check level and there was foamy/bubbly fluid near the top of the tube.  I started it again and tried cycling left to right figuring it needed to push more excess fluid out, but the assist was getting worse and feeling tighter.

So then I thought I must be letting air get sucked in through the fill tube making it worse.  I replaced the dipstick and tried starting and cycling the steering again with intermittent assist and some really tough spots.  So I shut it down to look for advice.

1) When installing the steering box, the mechanism did get turned some from left to right as I connected the rag joint and drag link.

2) I am unsure if the bleeding procedure I used is correct.  I saw one from Dorman with the rebuilt pump that said to disconnect the return hose when adding fluid until clear, bubble free fluid came out.  I did find a small amount of fluid pooled around the return hose at the box connection, so that could be an air intake source.

Finally, I thought, gee, did I maybe get the hoses switched at the box and sending high pressure in the low side.  I checked all the restoration guides that show the high pressure going in the port closer to the engine, which is how mine is connected.

Any suggestions.

kcmash

For bleeding the pump, raise the front wheels slightly off the ground, either a floor jack under the cross member or better yet jack stands under the cross member. Don't get it too high though. You will get some foaming, but it should work itself out. I have removed and replaced my PS box at least 5 times and never had any of the problems you describe. As for the connections on the box, it is not possible to get them switched, two different sizes, one is 5/8 npt the other 11/16 npt. To tighten the nuts on the box connections, I use a claw foot flare type wrench and long extension , they are very hard to get tight with just a flare wrench, no room to work!

Did you center the input shaft prior to installing the box? Moving it 1/2 turn or so left or right is normal to get the rag joint bolts in. Easy way to tell is the shaft clamp bolt head should be upper most looking down on it. You would have to be 1 full turn off because of the flat on the input shaft to get more turn one way than the other if that makes any sense. Your wheels should be straight ahead and your s/wheel centered with equal turns left to right. A 17.5:1 fixed ratio is 4 turns LTL, Variable is 3 1/8 turns LTL.

 

[Bentworker]

Personally I take the weight off the front wheels and repeatedly turn it from lock to lock with the engine off.  That will get most of the air out of the box.  After that I do some more lock to lock turns with the engine idling.  Be sure to check fluid often.  If it turns into a foamy mess stop and wait for all the bubbles to rise- then try again.

If that does not sort it out let us know.

 

[kcmash]

Geoff,  I am trying to follow you.

The input shaft is keyed to the rag joint, the rag joint keyed to the input on the box.  I an not happy with the way the steering column shaft does not go further into the rag joint, but  it is in about 1/2 inch.

So if my steering wheel is off, no biggie, correct.  I do need to adjust it by about 10 degrees anyway. 
 

I appreciate the suggestions on the unloaded bleeding.

kcmash

 

[Bentworker]

@kcmashThe wider slot on your steering column that engages with the 9/16” diameter pin on the rag joint should be at 12 O’clock (non tilt column)- and your steering wheel should be at 12 O’clock (match the wheel to the steering shaft) The input to the steering box is the monument you set everything else to so that you have equal left to right steering.  You may have to adjust tie rods or move your pitman a spline or two (if it does not have the double splines that ensure it it clocked correctly on the sector shaft).

 

[kcmash]

So mine is a tilt column.  The shaft from the steering has a flat milled on one side which keys to the rag joint.  Only one way to align it.

i did not realize at the time that there is a clocking scribe in the 2 spoke steering wheel, so I eyeballed it during assembly.  Since the car had not been running yet I did not realize I was off when the car is moving.

Does that make semse?

kcmash

 

[Bentworker]

Tilt columns are like unicorns!

I think the steering box input shaft flat is at 12 O'clock when it is centered.  Just to be clear I am not 100% positive on that...

 

[Stanglover]

Personally I take the weight off the front wheels and repeatedly turn it from lock to lock with the engine off.  That will get most of the air out of the box.  After that I do some more lock to lock turns with the engine idling.  Be sure to check fluid often.  If it turns into a foamy mess stop and wait for all the bubbles to rise- then try again.

If that does not sort it out let us know.

Engine off. Good point. 

 

[Stanglover]

Geoff,  I am trying to follow you.

The input shaft is keyed to the rag joint, the rag joint keyed to the input on the box.  I an not happy with the way the steering column shaft does not go further into the rag joint, but  it is in about 1/2 inch.

So if my steering wheel is off, no biggie, correct.  I do need to adjust it by about 10 degrees anyway. 
 

I appreciate the suggestions on the unloaded bleeding.

kcmash

kc, So, I have zero experience with unicorns!! tilt columns. I understand that the rag joint coupler is/could be different to the non-tilt type. If that's the case, hopefully someone else whos does have experience with tilt's can chime in. None the less, if everything is centered or clocked correctly, the flat on the input shaft will fit the splined hole in the rag joint. I am not aware of any differences for input shaft diameter or number of splines for PS boxes with tilt or non tilt. The Ford type Saginaw PS box has 7/8" dia. 31 spline input shaft and is the only one I know of.. 

For a non tilt column, the best aftermarket rag joint or coupler and the one I use is the Lares 201. However, this one has the "safety pins" both the same diameter, but long enough to properly engage, so one does need to pay attention when assembling. The Scott Drake version has the pins too short to engage the slots in the column "what do you call it", therefor the fail safe aspect is zero should the rubber disc ever fail. 

Hope this is getting you closer. 

 

[Hemikiller]

Agree with unloaded bleeding. I run it back and forth a half dozen times, then let it sit for a bit, which give the air in the fluid time to travel  to the reservoir. Dorman's recommendation is for expediency, when you have a customer waiting that's going to come right back if the PS is making noise. 

Hoses are pretty much impossible to accidentally switch, the fittings are different sizes. 

 

[kcmash]

OK gang,

I took it out for a short drive after the unloaded bleeding the other day.  I did about 20 cycles left to right with wheels off the ground and the engine off.

I still have a little air to bleed as there is some slight groaning from the steering.  The steering felt nice and the assist felt great.  

So what was wrong with mine?

1) A retaining ring was not seated properly that affected the rotating valve.

2) A defective High Pressure hose that failed at the crimp.  Now the bad retaining ring could have caused a detrimental pressure situation that taxed the hose, but the hose did slip out of the crimp.

I am feeling a lot better about this now.

kcmash

 

[kcmash]

How do I know when they are bled. 20 plus cycles with the car off, then it overflows at the stops when cycling while running.

Let me know.

Kcmash

 

[Hemikiller]

I perform the bleed cycle with the engine running at idle and wheels off the ground. Snip below from the factory shop manual. If you're cycling the steering with the engine off, it's going to push the fluid into the reservoir and cause it to overflow.

 

[kcmash]

Still playing with the power steering. It sounds like crap and really loads the engine down.

Lots to fix for drivability. This thing is frustrating.

Kcmash

 

[Bentworker]

Did you ever try a different pump?