How To: Rebuild Steering Rack

[Ron]

http://www.dmcnews.com/Techsection/Steering%20Rack%20Rebuild/Steering%20Rack.pdf

EDIT: Link above broke. See:
https://drive.google.com/file/d/1FRZxVOtv9gP6GQe5IxwfvIEOOG9DUNJZ/view?usp=sharing

Thanks Mark D!

[ALEXAKOS]

http://www.dmcnews.com/Techsection/Steering%20Rack%20Rebuild/Steering%20Rack.pdf

All I wish to add to this tutorial is that the PVC used to guide the inner bar, needs some shafts to allow the fluid to move in and out of the rack.
Just like the original part did. The way this fella sealed the gateway between the two ends, it will create hydrolic pressure between the two ends making the steering rack stiffer.

Images supplied soon;)

[Spittybug]

Good point, maybe...

When I did mine I also have it as a tight fit, minimizing the fluid transfer. I was thinking that it might be a problem for the passenger side tie rod joint inside the boot, but I can't see how that joint would ever be "bathed" in fluid anyway. I ended up inserting a pin through the side wall of the rack tube into the bushing, so I'm sure I won't have to worry about any hydraulic pressure popping my bushing out. Thinking about it though, there really isn't a lot of force to push the fluid around. The rack moves relatively slowly and there isn't any kind of tube pressurization since the other end is open.

[ALEXAKOS]

That is a strong argument Owen.:thumbup:
I just noticed the original part that was grabbing the rod only at 50% of its total surface leaving 4 blanks in between. First thought was liquids passage, second was also less friction and air passage. Since the boots are tightly sealed on both ends, it leaves little "communication" between the two compartments left and right from that PVC tube replacement.

I am actually reproducing those with Polyurethane replacements of that seal as well as the filler inner cap as that was also melted... for some reason.

Will have photos in 2 days.:raveon:

[ALEXAKOS]

Right, here are the originals next to the copies I made with poly.
http://i821.photobucket.com/albums/zz135/alex-akos/delo%20resto/null_zps9074bbaf.jpg
Right the melted filler cap knob left my replacement
Goes like this:
http://i821.photobucket.com/albums/zz135/alex-akos/delo%20resto/null_zps05de6976.jpg
http://i821.photobucket.com/albums/zz135/alex-akos/delo%20resto/null_zpsb8e11c18.jpg

Then the centering cylinder that was ripped.
Left the original, right my poly repro
http://i821.photobucket.com/albums/zz135/alex-akos/delo%20resto/null_zps56af3bfc.jpg
notice how large the gaps are on the original. I believe the main reason is minimal friction cause it was made of hard rubber


fitting
http://i821.photobucket.com/albums/zz135/alex-akos/delo%20resto/null_zps6421c81b.jpg
http://i821.photobucket.com/albums/zz135/alex-akos/delo%20resto/null_zps4a63f131.jpg

I rounded up the sharp corners

[Helirich]

Is the original post link gone? Doesn't seem to work for me. I think I need to make a poli-bushing for the pax side. Mine has nothing there. What holds the bushing in? My rack is nice and tight. Everything seems good but that one end. Im probably going to make the bushing tomorrow. If anybody has some good imput on this, please comment.

[Mark D]

PJ Grady sells replacement steering rack bushings. I bought a set like 10 years ago and they are still holding up well. I don't think they have them listed on the website, you just have to call and ask.

http://dmctalk.org/attachment.php?attachmentid=29860&d=1407416483

He also reproduces the cup shaped bushings for the inner tie rods.

http://dmctalk.org/attachment.php?attachmentid=29862&d=1407416608

[Mark D]

I have that PDF as well that was linked above but apparently no longer exists. I put it up on my google drive here:

https://drive.google.com/file/d/1FRZxVOtv9gP6GQe5IxwfvIEOOG9DUNJZ/view?usp=sharing

[Helirich]

So I guess the bushing is just held by press fit? One guy mentioned he made a pin to hold it. Not quite sure how that would work. (The pin would have to be less than an 1/8"?)

Edit, just read your write up, Mark. Great job! Thanks.

One more edit, Mark, do you think it would be possible to replace that bushing in the car?

[Helirich]

To answer my own question, yes, you can replace the bushing in the car. I put a threaded hole in the side of my bushing and used a very short screw to lock it in place. Then I put the boot rubber/clamp over the screw head to lock it in place.

One thing I noticed, the first bushing I made was tight. It made the steering wheel turn kind of hard. After honing it out, it moved easy. I wonder if you could size it so it would dampen your steering. I might experiment with that later, I don't have time right now.

[82DMC12]

I found this thread and proceeded to completely disassemble my PJ Grady - rebuilt rack today. It started by noticing my passenger side boot had a tear on the top of it (so oil can't come out), so I ordered a set of new boots from DMCMW. I did the driver side first, no big deal but it was pretty hard to stretch the boot over the rack end. Finally got it. Then did the passenger side. Well that side was more rotten so it came off the tie rod in two pieces, and I found a fair amount of metallic debris in the boot that appeared to at one time make a round shape. Also some metal junk at the end of the rack tube. I then found the rack had enough play in it where I could move it left - right - up - down. Further investigation into this thread and I found the metal crap must have been, at one time, my passenger side end bushing because there was nothing remaining there. I assume Grady is/ was using a metal bush at one time during my rebuild, which would have been like 15 years ago.

Finding the debris made me worried about more metal crap inside the tube so I proceeded to remove the whole rack. In addition to the shop manual instructions I had to loosen the top U-joint as well to get enough movement of the intermediate shaft to slip the bottom U-joint off the pinion. Thank God the last time I was in here I put a lot of antisieze all over these threads. They moved pretty easily once the lock screws were removed from the U-joints ( I have Darryl Tinnerstedt's U-joints)

In taking the rack apart, I also found a small stainless washer under the spring that tensions the oil cap. That is not mentioned in this guide It is between the spring and the white plastic spring holder.

My white plastic spring-holder under the oil cap is different - it comes in from INSIDE the tube and has a flat lip that has the same radius as the tube. Therefore it's impossible to remove the white piece after removing the oil cap - it has to come out after the rack has slid out of the tube.

Also, not sure if this is typical, but there is a very thin washer under my large inner race (where the inner race is butted up into the rack. The washer has been drilled sideways a bit so the hole is oblong. I found this extremely helpful in removing my outer race from the bottom of the tube because I was able to get a hook tool into the part of the oblong hole that gets under the race and pry upward to get the race out. Once I had it loose, I turned the rack over and set the pinion side onto a piece of wood while tapping on the flat side of the pinon holder with a plastic mallet. This loosened the inner race so I could grab it and pull it out.

So, now I just need to get a new passenger side bushing (I am checking with Grady and if he doesn't have it, I see Josh sells it) and I can put it back together and once again have a perfect steering rack.

[82DMC12]

Well, I'm back in this thread because I'm actually having a problem with my rack after taking it apart and putting it back together again. I got an alignment after completing a frame-off restoration and the tech noted, and showed me, that the passenger side inner tie rod has play in it. Once the alignment was complete, and I put the car back into semi-regular use, it became apparent that there is play in the steering wheel before the tire direction changes. The wheel moves back and forth a couple degrees before it moves the rack side to side. While under the car, the tech explained that he knew the tie rod was loose because it took a bit of turning to get the toe to change on the computer, also if you grab the knuckle from underneath and move it in and out, you can see the rod moving in and out but the driver tire is stationary.

So, I will be removing the rack once again to see what happened. I suspect the plastic cup or spring could be damaged, but I'm also thinking it is possible to have insufficient spring tension if the two nuts that hold the inner tie rod are outboard too far. That would allow play in the inner joint. Perhaps that's all the problem is.

Does anyone have recommendation for how to set that spring tension? Is is possible for the inner tie rod to be too tight? Are you supposed to take all the movement out of the joint? How much play should there be, if you push the tie rod up against the joint (compressing the spring)?

[82DMC12]

The correct answer to my above question is 5 to 7 lbs tension on the tie rod ends.

That is one detail missing from the rebuild PDF but it is essential to a successful project. When I first followed the instructions, I tightened the tie rods just enough to remove all play, but didn't get any pre-tension on the springs that the cups push on. I have now removed my rack, drilled out the pins, replaced the cups and springs since I was in there again, and now set the two silver nuts so that the ball end of the tie rod is pushing into the cup with enough force to required 5 lbs of tension to lift the tie rod as per a spring scale. Then inserted new pins, topped up the oil, and re-installed. Now there is no more play in the rack. Thank you to Rob Grady for supplying the upgraded parts and the advice regarding setting the tension!

69696









Checking tension prior to opening up the tie rod - less than 500 grams, or essentially zero tension since the tie rod was floppy, yet no play in the joint.











69697









After adjusting the location of the silver nuts, and thus, the tension, now I had 2.25 to 2.5 kg force required to pull the tie rod end through an upward arc. The tie rod now stays in whatever position you put it in.