Author Topic: Fast Ratio Steering Box Rebuild  (Read 18360 times)

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #15 on: January 18, 2011 - 03:19:04 PM »
Mopar Action did a story on the springs last summer.
I'll try to find it.

That could be really helpful; thanks for your time.
'72 'cuda




Offline Kapteenikosmos

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Re: Fast Ratio Steering Box Rebuild
« Reply #16 on: January 18, 2011 - 03:56:47 PM »
I just checked through the pics I have and you can change the upper spring without much work. Open the spanner nut from the input shaft side and wiggle the aluminium head off from the actual housing. If I recall right it needed bit persuasion because its slightly hard to get a good grip but it is only held there with an o-ring. The upper spring is just behind that. To get access to the lower spring you would need to open that notched nut and tear the whole power piston assembly apart.

The service manual has a procedure to tighten the nut so that the friction caused by the thrust bearing the nut is holding is correct but basically if you wouldn't change the bearing you could just mark the nut position and tighten it back there.

I'll upload the pics I have to photobucket tomorrow and post the link here.
Ville

1967 six banger Mustang
1973 Challenger (under restoration)
1997 Lincoln Mark VIII LSC (daily driver)

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #17 on: January 18, 2011 - 05:22:21 PM »
I just checked through the pics I have and you can change the upper spring without much work. Open the spanner nut from the input shaft side and wiggle the aluminium head off from the actual housing. If I recall right it needed bit persuasion because its slightly hard to get a good grip but it is only held there with an o-ring. The upper spring is just behind that. To get access to the lower spring you would need to open that notched nut and tear the whole power piston assembly apart.

The service manual has a procedure to tighten the nut so that the friction caused by the thrust bearing the nut is holding is correct but basically if you wouldn't change the bearing you could just mark the nut position and tighten it back there.

I'll upload the pics I have to photobucket tomorrow and post the link here.

Thanks for that and any pics you have would be very welcome.  Unfortunately it is my lower spring which is the problem (my upper spring seems to be acting fine).  I'm not sure what's happened but the car was standing a long time before I got it and I think the lower spring may have just got stuck flat, if you know what I mean.  If that's the case then even if I could just free it off ...?..!
'72 'cuda

Offline Kapteenikosmos

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Re: Fast Ratio Steering Box Rebuild
« Reply #18 on: January 19, 2011 - 02:27:46 AM »
Thanks for that and any pics you have would be very welcome.  Unfortunately it is my lower spring which is the problem (my upper spring seems to be acting fine).  I'm not sure what's happened but the car was standing a long time before I got it and I think the lower spring may have just got stuck flat, if you know what I mean.  If that's the case then even if I could just free it off ...?..!


Here is a link to the pics I took:

http://s264.photobucket.com/albums/ii186/73chal/Power%20steering%20gear%20rebuild/

Seems like I could have taken more pics but I was in a bit of a hurry when I was working with it.

Hmmm, So you are feeling the reaction springs only when turning the wheel to one direction while the engine isn't running? If I recall right I had some issues when I was assembling the power piston and ball screw assembly back into the housing. The assembly tend to stuck so that the other spring was always pressed to the bottom. It took a couple of tries before I got it right.

Have you removed the power steering valve and checked the movement of the lever that actuates the valve? It might be possible that the lower spring has broken apart or if the previous owner has tried to rebuild the box and forgot to install the lower spring altogether?

Easiest way would be to order the rebuild kit from Rock Auto or similar and just tear it apart. It takes only a couple of evenings and it can be done with fairly common tools with some improvisation.

Ville

1967 six banger Mustang
1973 Challenger (under restoration)
1997 Lincoln Mark VIII LSC (daily driver)

Offline nqkjw

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Re: Fast Ratio Steering Box Rebuild
« Reply #19 on: January 19, 2011 - 04:55:11 AM »
I rebuilt a PS box in High school & have not attempted it since , ,Omega makes seal kits for it & I bet it is the same kit for fast ratio as it uses the same housing

Quick ratio PS box kit is different.
The shafts are a smaller diameter.
Went through this hassle when I did mine and you can only imagine the problems trying to figure out in Australia what was different since the same kit is supposed to fit all from 1957 through to 1974.
This is how I found out mine was a quick ratio box.
How it ended up in mine is anyone's guess :clueless:
Burnouts are cool but Traction is the Action

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #20 on: January 19, 2011 - 06:25:39 AM »
Here is a link to the pics I took:

http://s264.photobucket.com/albums/ii186/73chal/Power%20steering%20gear%20rebuild/

Seems like I could have taken more pics but I was in a bit of a hurry when I was working with it.

Hmmm, So you are feeling the reaction springs only when turning the wheel to one direction while the engine isn't running? If I recall right I had some issues when I was assembling the power piston and ball screw assembly back into the housing. The assembly tend to stuck so that the other spring was always pressed to the bottom. It took a couple of tries before I got it right.

Have you removed the power steering valve and checked the movement of the lever that actuates the valve? It might be possible that the lower spring has broken apart or if the previous owner has tried to rebuild the box and forgot to install the lower spring altogether?

Easiest way would be to order the rebuild kit from Rock Auto or similar and just tear it apart. It takes only a couple of evenings and it can be done with fairly common tools with some improvisation.


Hey man your photographs are sooooo helpful.  This is all making sense now.

I have checked my valve body and the pivot lever and they are fine.  The problem I can detect is as you say with the engine off.  The input shaft will turn "left" and move slightly out of the box as it should and then return on it's own, but when I turn it "right" it moves a similar amount into the box but doesn't return by itself.  In terms of the valve lever, it moves back on a left turn and then springs back to the middle but on a right turn it moves forward and then stays there until I rotate the shaft back (though actually I can just see it move back a tiny little bit on its own).  [I may have got my forwards and backs mixed up but I think you get what I mean]

When I got the car it had been standing for a long time and I remember when I first got it running the steering immediately went all the way over one way, so of course I thought someone must have been playing with the valve body, but now I am thinking maybe the car was parked up a long time with pressure on the lower spring and it got stuck like that.  When I adjusted the valve body to cure the self-steering I guess I put it into the "slack" area where the lower spring ought to be operating - which could account for the strange steering symptoms I have (no self-return out of corners and unable to turn the sector shaft manually).  I figure if the valve is off center so that the two sides of the power piston are not able to exchange fluid when I release the steering wheel then it will have created a passive hydraulic lock.

In your photos I think I can see both the reaction rings but perhaps you can confirm this.  The upper ring is on the bench in photos 4919 and 4920 and the lower ring is sitting inside the casing in photo 4924, is that correct ?

If that is correct then I think I was right to suspect that both rings can be replaced without disturbing the staked nut and without removing the main worm and power piston assembly from the casing.  The ring in your 4924 looks about ready to fall out on its own, and I think I see the hole above it where the little lever comes through.

One thing I can't see in your photos is how the spacer sits inside the unit.  The "spacer" is the name in the manual given to the large ring that looks like a pulley and which I assume operates the bottom end of the little lever, I can see it assembled between the end cover and the piston head in photo 4928 and it looks like it must just slide on over the bearing that I can see under the nut in 4926.  Can you tell me is that right?

Many many many thanks.
« Last Edit: January 19, 2011 - 06:31:26 AM by UKcuda »
'72 'cuda

Offline Kapteenikosmos

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Re: Fast Ratio Steering Box Rebuild
« Reply #21 on: January 19, 2011 - 10:39:06 AM »

In your photos I think I can see both the reaction rings but perhaps you can confirm this.  The upper ring is on the bench in photos 4919 and 4920 and the lower ring is sitting inside the casing in photo 4924, is that correct ?

If that is correct then I think I was right to suspect that both rings can be replaced without disturbing the staked nut and without removing the main worm and power piston assembly from the casing.  The ring in your 4924 looks about ready to fall out on its own, and I think I see the hole above it where the little lever comes through.

One thing I can't see in your photos is how the spacer sits inside the unit.  The "spacer" is the name in the manual given to the large ring that looks like a pulley and which I assume operates the bottom end of the little lever, I can see it assembled between the end cover and the piston head in photo 4928 and it looks like it must just slide on over the bearing that I can see under the nut in 4926.  Can you tell me is that right?

Many many many thanks.

I just picked up my spare box to refresh my memories. I took a few pics that will clarify the assembly but it seems like I have lost the data cable for my camera so it will take tomorrow before I can upload the pics at work.

To get access to the lower spring you will have to open the nut and pick apart the bearing/lever support whatever it is called assembly. The spring shown in the pic 4924 is the second upper spring that was in my assembly and the lower spring can be seen on the pic 4926. I'm holding/flexing it with a screw driver.

Ville

1967 six banger Mustang
1973 Challenger (under restoration)
1997 Lincoln Mark VIII LSC (daily driver)

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #22 on: January 19, 2011 - 04:04:58 PM »
The spring shown in the pic 4924 is the second upper spring that was in my assembly and the lower spring can be seen on the pic 4926. I'm holding/flexing it with a screw driver.

Ah, I see.  I had overlooked the fact you had found two springs on the upper side.

But at least I am feeling OK about tearing into it now, I think my next thing is going to be finding a source of replacement reaction springs.  I have found these part numbers:

03643129 = regular springs

03643169 = cop car springs

Obviously I would prefer to go with the cop springs, and the cop springs also seem to be listed for some later model truck applications, but Google can't seem to find anywhere that sells them, and hardly anywhere that even sells the standard springs.

Anyway, thanks again for your help here.
'72 'cuda

Offline cwestra

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Re: Fast Ratio Steering Box Rebuild
« Reply #23 on: January 24, 2011 - 06:07:52 PM »
Quick ratio PS box kit is different.
The shafts are a smaller diameter.
Went through this hassle when I did mine and you can only imagine the problems trying to figure out in Australia what was different since the same kit is supposed to fit all from 1957 through to 1974.
This is how I found out mine was a quick ratio box.
How it ended up in mine is anyone's guess :clueless:
Any idea where to get the correct kit for fast ratio?  All I am planning to do is fix the leak, so seal kit is all I need.  Rock Auto (as suggested above) has the regular kit but the guy is checking with the company to see if it will work with my fast ratio.  I am assuming he'll find out it won't based on what you are saying.
Corey - in Northern Indiana

Offline boydsdodge

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Re: Fast Ratio Steering Box Rebuild
« Reply #24 on: January 24, 2011 - 09:08:49 PM »
I apologize it wasn't in the steering box it was in the pump that they did the mods.
Here is the story anyway.
http://www.moparaction.com/tech/beep/PUMP_IT_DOWN-re-v1.4.pdf
Jackson from Toronto.

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #25 on: January 25, 2011 - 01:20:17 AM »
Any idea where to get the correct kit for fast ratio?  All I am planning to do is fix the leak, so seal kit is all I need....


Don't know on the seal kit but if it helps you, I fixed my problem last weekend all with the p/s box still on the car and I discovered you can easily replace the upper shaft seal (and some other parts) without removing the box from the car.  The manual says you can do the lower seal in the car but doesn't mention the upper one.  As you are only doing your seals and it can be a 'mare to remove the box (esp. if you have headers) I thought this is good news.

I took some photographs but I can't get them to load to photobucket.  I'll put up a thread about it when I get my photos to work.

I apologize it wasn't in the steering box it was in the pump that they did the mods.
Here is the story anyway.
http://www.moparaction.com/tech/beep/PUMP_IT_DOWN-re-v1.4.pdf


Thanks, by coincidence I saw that "pump it down" article the other day.  I am a bit skeptical on their theory to be honest, but I guess it can't hurt to have the pump pressure limited to what you actually need.
'72 'cuda

Offline Kapteenikosmos

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Re: Fast Ratio Steering Box Rebuild
« Reply #26 on: January 25, 2011 - 02:32:38 AM »
Thanks, by coincidence I saw that "pump it down" article the other day.  I am a bit skeptical on their theory to be honest, but I guess it can't hurt to have the pump pressure limited to what you actually need.

I also agree. Firming the steering won't work that way. Or yes, it works but not the way you would like it to work. The pressure relief valve is there only to relief the maximum pressure in the system ie. when you are turning the wheels against end stops. It's only there as a fuse. Slat six engines have a lower pressure because the engines might stall with higher pressure setting when idling and turning wheels against end stops.

The whole power steering system works so that the control valve is controlled via reaction springs by the driver when turning the wheels. The valve is so called "open-centre" valve which means that when it is in the middle position, the oil flows through the valve back to the reservour with very low pressure drop. When you are applying torque to the steering wheel the, some of the force is transmitted through the reaction springs to the valve lever which moves the spool. Now when the spool moves it starts to close up the passage back to reservoir and keeps the flow path open to the one side of the power assist piston. Because the flow returning to the reservoir is throttled the pressure inside the power steering box starts to increase thus creating the power assist to the steering via the power piston. So basically the only way to affect the amount of power assist would be a redesigned valve spool or stiffer reaction springs.

So when the mopar action guys dropped the relief pressure they only changed the amount of maximum power assist. When the maximum pressure is dropped enough, it will in a way increase the firmness but you would mainly notice it while turning the wheels on stand still. To feel it while cruising, you would have to drop it really low and that would cause hard steering when parking etc.

UKCuda, you said that you got your steering working again. Did you change the reaction spring also when the box was still in the car?

Ville

1967 six banger Mustang
1973 Challenger (under restoration)
1997 Lincoln Mark VIII LSC (daily driver)

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #27 on: January 25, 2011 - 03:53:05 AM »
 :iagree:  The problem I was having was caused by the upper reaction spring and its inner steel ring having been assembled (by previous person or persons unknown) in the wrong order.  The effect was to prevent that spring from doing anything useful.  Not knowing that was the real problem I had compensated by moving the valve body slightly away from the effect of the functioning spring to prevent self-steering.  In turn this put the "open both ways" section of the valve in the wrong place and prevented the two sides of the power piston from exchanging fluid when the steering was centered, hence my steering couldn't be turned from the linkage side.

I was able to remove and re-assemble the upper spring and related components with the box in the car.  It was quite easy.  I also removed and checked the central spacer (which acts between the reaction springs) and that allowed some inspection of the lower reaction spring/assembly (which was OK).

I didn't go any farther because I didn't want to disturb the input pre-load without good reason, but I'm pretty sure if I wanted to I could have removed the staked nut and bearing and then replaced the lower reaction spring.

I found that access into the top end of the box is actually quite good after I removed the whole steering column as a unit (which only took about 30 minutes).  The only issue is getting everything lined up on re-assembly so the various rings slip into position against one another, but this turned out to be quite do-able with some long nose pliers and a good inspection light.  Definitely a lot easier than removing the box from the car.

My only problem now is that my wheel alignment is a little out and pulls slightly to one side since it was set up with the valve body in the wrong position.  I have good return out of corners though and the "feel" in the steering seems OK, even though I am still on standard reaction springs.

As I said, I'll post up a proper thread when I can get my photos to load.
'72 'cuda

Offline cwestra

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Re: Fast Ratio Steering Box Rebuild
« Reply #28 on: January 25, 2011 - 03:38:10 PM »
Don't know on the seal kit but if it helps you, I fixed my problem last weekend all with the p/s box still on the car and I discovered you can easily replace the upper shaft seal (and some other parts) without removing the box from the car.  The manual says you can do the lower seal in the car but doesn't mention the upper one.  As you are only doing your seals and it can be a 'mare to remove the box (esp. if you have headers) I thought this is good news.

I took some photographs but I can't get them to load to photobucket.  I'll put up a thread about it when I get my photos to work.
 

Thanks, by coincidence I saw that "pump it down" article the other day.  I am a bit skeptical on their theory to be honest, but I guess it can't hurt to have the pump pressure limited to what you actually need.
Good to hear.  Not sure where my leak is coming from but I may just replace the upper seal in the car like you did and see if the leak goes away.  Your pictures would be great if you find the time to upload them.  Thanks UKcuda.

Still wondering what kit to use for the Fast Ratio box.  Anyone?
Corey - in Northern Indiana

Offline UKcuda

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Re: Fast Ratio Steering Box Rebuild
« Reply #29 on: January 26, 2011 - 01:42:52 PM »
Good to hear.  Not sure where my leak is coming from but I may just replace the upper seal in the car like you did and see if the leak goes away.  Your pictures would be great if you find the time to upload them.  Thanks UKcuda.


Here you go:  http://www.cuda-challenger.com/cc/index.php?topic=74593.0

If you are just doing the upper seal I can put a micrometer on where the column goes into the box if you like - that should tell you if my upper seal is the same internal diameter as yours.
'72 'cuda