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Steering Rack Disassembly and Refurb


Captain Obvious

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I've been doing a bunch of suspension work to my 77 this off-season and part of that work has been on my steering rack. I suspect this is old hat for lots of people, but it's my first time this deep into the rack and I've been trying to take pics of the interesting spots along the way.

This whole project started with the rack mounting bushings. My previous owner installed polyurethane bushings on the rack mounts and they didn't look like right. The project snowballed from there, but let's start with the bushings.

On the pass side, the bushing looked too narrow for the mounting slot on the rack and after some digging on the forums, it appears that the width of the P/S rack mounting slot got wider on the later cars. It appears that he used an early kit on a later car. Here's a pic of the bushing he put in. You can see the gap where the mounting slot is wider than the bushing:

P1050327_zps5ccd3dad.jpg

The solution appears to simply use the correct year bushing kit. Here's my replacement bushing installed. It was a tight fit. I even had to put a little silicone grease on the bushing and tap it into place with a plastic mallet. Much better fit:

P1050337_zps52a7582f.jpg

I've seen pics of this before from others, but for posterity, here's the older narrow style compared to the newer wider style:

P1050328_zps3f98c0af.jpg

And on the driver's side there was a large gap where the bushing didn't wrap around the rack properly and was pinched by the mounting strap. Here's a pic of the driver's side bushing. You can see the gap and notice the deformation on the left side from not fitting into the mounting strap correctly:

P1050330_zps2d98bee8.jpg

Problem was... When I first installed my replacement bushing, it was no better than the one that came off the car. I had the same problem and couldn't get the bushing to wrap around the rack far enough and I ended up with a huge gap where the ends were supposed to meet.

After looking things over, I came to the conclusion that the replacement poly bushing wasn't designed properly. The rack has a smooth radius fillet on the inside corners at the bottom of the slots, while the bushings have squarer corners molded into them. As a result, the bushings don't fit comfortably into the slots.

Here's a shot of the shot in the rack. Note the smooth rounded fillets in the corners:

P1050254_zpsab864b41.jpg

And here's a shot of the bushing that's supposed to fit in that slot. Note the inside corner that is much sharper than the receiving slot in the rack:

P1050252_zps91495a38.jpg

Thankfully the poly was hard enough that I was able to cut it with a new very sharp fine tooth file. Using a file I was able to round the inside corners of the bushing to better fit the rack. Here's a shot after I rounded the corners:

P1050251_zpsae6bd818.jpg

Finished filing both sides of the bushing and tapped into place with a plastic mallet. Note how much smaller the gap is once the bushing fits snug in the slot and slides all the way to the bottom of the groove without hanging up on the corners:

P1050256_zps8066a85e.jpg

That's what started the project. I'll post more pics as the work progresses.

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siteunseen, I remember talking about those two little plastic plugs that are circled in your pics. I took some close-up pics of mine. Here's one side:

P1050333_zps92e11a4b.jpg

And here's the other:

P1050334_zps89ecb52c.jpg

Still not sure what they are, but I can tell you that they are NOT plugs for grease fitting holes. Not only are they too small, but if you look inside the rack tube, there are no holes through. Here's a pic inside the tube No holes:

P1050335_zps2e43079d.jpg

So after looking and picking at them, my only theory is that they have something to do with the fitting and alignment of the two major components of the rack tube. I'm thinking that maybe since alignment of the long tube into the cast portion that houses the pinion gear is important, that maybe they loosely fit the two parts together, locked them in an alignment jig, and then used a hard setting thermoplastic to lock the two together. Similar to what they did with the throttle linkage? Just a theory.

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I have tried everything else but the rack bushings. So maybe I will take mine out soon. Who supplied the bushings?

rcb, Haha! Well I gotta admit something here...

I've been doing all this suspension work you see... And I knew that I had an old set (NOS) of strut inserts packed away in a box in the storage area of the garage. Now mind you, I bought those struts maybe fifteen years ago for the 260 I was working on at the time. Well when I started all the suspension work on my current 280, I went looking for those struts.

I found the struts, but they are rears for the 240/260 and won't fit anywhere on the 280. BUT I also found a box of other parts that I bought at the same time with the intention of putting them on the 260. Been so long, I completely forgot I ever even bought them. And one of the things that was in that NOS box was the steering rack bushings. How unbelievably convenient!!

So, long story short, I bought them so long ago that I have no idea where. Probably MSA or Black Dragon.

And for siteunseen, I didn't consciously choose the black. That's what I found in my NOS mystery box! :D

Here's a pic of the paperwork that came with them. Has Mfgr name and P/N's on it. No idea if this place is still in business, but that's all I got! You can see on the paperwork that they differentiate between "early" and "late", and the P/N I bought was for "late":

P1050365_zps93cd6dfc.jpg

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After I got the bushings sorted out, I disassembled the rest of the rack. This means you have to pull the inner tie rods off. You really only need to remove one end, but since I wanted to clean out all the old grease, I removed both ends.

Remove the dust bellows and you're looking at this:

P1050285_zps62fe9591.jpg

Remove the plug from the inner tie rod grease port:

P1050287_zps89185719.jpg

Loosen the lock a little bit nut:

P1050289_zpsa81eef34.jpg

And unscrew the inner tie rod from the end of the rack gear:

P1050290_zpsfed6ad38.jpg

After you get the tie rod off, inside you'll find the ball seat and it's associated spring. In this pic, the seat is out laying on the paper towel, and you can see the tip of the spring poking out of the hole in the end of the rack:

P1050294_zps4121dc31.jpg

Ball seat and spring cleaned up:

P1050299_zpsc014a7c7.jpg

Pull the lock nut and "spacer" off the end of the rack gear and you're left with this:

P1050300_zps686a3c01.jpg

If you pull the other inner tie rod end as well, just be sure you don't mix up the parts from the ends and make sure you put everything back on the same end it came from originally.

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Got some more pics uploaded. To get the rack gear out of the main tube, you have to take off the tension adjust shoe and the pinion gear. Most of this stuff has been handled before so I'm not going to include as many pics, but thought I would include some.

To get the tension adjustment shoe out, first remove the lock ring:

P1050302_zps33482331.jpg

Then unscrew the big slotted adjustment cap exposing the parts inside. Remove the washer and spring. Note that I could not fish the tension shoe out of the hole from here. It's not in there real tight, but there's just no place to easily grab it down in the blind hole. I was able to push it out easily from the other side once the rack gear was removed from the housing. You can see the shoe still installed in the housing:

P1050305_zpse69b2063.jpg

To get the pinion gear out, remove the two bolts holding the retainer in place and pull the retainer off. Note that I put some masking tape over the shaft splines to protect the grease seal while it is being slid over the splines:

P1050307_zpscbfff486.jpg

Pull the pinion shaft, upper bearing, and gear up and out of the rack. Mine came out without a fight:

P1050308_zps8ce1da7c.jpg

Don't lose or bend any of the spacer shims that adjust the pinion shaft end play:

P1050323_zps84e139e2.jpg

After removing the pinion gear, here's what it looks like inside the housing. The rack and lower pinion bearing are still in place:

P1050310_zpsd49ebbdc.jpg

Once you have the tension shoe loose and pinion gear removed, you can silde the rack gear out the end of the housing. Obviously, if you only removed one inner tie rod end, then that's the direction you'll have to go, but if you took them both off like I did, then it will slide out either end. And then once the rack gear is out, push the tension shoe out of the housing:

P1050313_zps2333c17c.jpg

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So one of the interesting things about the rack is that they used bronze bushings at the ends of the housing on which the rack gear slides. There is no discussion that I could find in the FSM's that talk about those bushings. I'm sure they're off the shelf items and are certainly replaceable with the right tools and replacement parts, but I'm guessing they were never intended to be a fixable item. If they're wallowed out, you're probably supposed to replace the whole steering rack assy? Note the lube groove cut in the bushing:

P1050321_zps4ce6337b.jpg

Also note the dent where the inner tie rod end grease plug was hitting the bushing at end of travel. This brings up a question for me... What is supposed to limit end of travel of the rack? On my rack, it was clearly the heads of those little bolts bumping up against the bushings and that just seems wrong. Makes me wonder if my rack was put together correctly. I'm going to file the deformation off the bushing, but unless I do something else, it's going to recur.

So back to the question about end of travel limit... I had these two black washers installed just inboard of the tie rod end lock nuts that floated stupidly in space between the grease plugs and the tie rod lock nut. The washer in question is just to the right of the grease hole in this pic:

P1050287_zps89185719.jpg

Here's another pic showing the washer after the tie rod end has been removed. The washer in question is top center in this pic. They are thick metal washers with a hard black vulcanized rubber coating applied to the outside:

P1050298_zpsc2f04f11.jpg

To me... That washer just screams "End of travel bump stop!!". But with the grease plug bolts installed as they were on my rack, it never gets that far. So I'm wondering if those grease plug bolts are correct. I'm thinking that if I used headless set screws instead to plug the grease holes, then not only would I stop denting my bushings, but I would also decrease my turning radius a little.

So a question for the suspension experts... What is is that is supposed to limit end of steering travel? Is it supposed to be those black rubber coated washers, or something else?

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So Chas, You mentioned in another thread that you cut the welds on your inner tie rods so you could tighten them up a little?

Do you have any pics of that process? I'm still thinking that I don't need to go to that extreme (yet?), but out of curiosity, how deep do you think you had to cut?

Hi Captain,

Great write up and the photo's are clear BTW. This thread is worth moving to the Tech articles section IMO.

Its going back 2 1/2 years, but I remember mine was loose. If you look at your first photo in post 7, your threaded end remains suspended in the air. Mine would fall down. It actually had a millimeter or so play in it.

By chance I discovered I could turn the welded lock nut, all be it with difficulty. It was welded, but still turned. I think that is what caused the excessive free play. It was then I decided to cut the weld with a small dremel cutting tool, since it couldn't get much worse than it already was. If I couldn't fix it, I would still need a new one. I retensioned it and tested it with a spring gauge according to the FSM specs and tacked the weld with a stick arc welder.

Looking at your unit, I wouldn't go that far either. You don't seem to have any problems there.

Interesting about those grease port plugs. I can't remember mine sticking out like that.

Someone in the past may have changed the originals after damaging them when greasing the rack?

Keep the posts coming:cool:.

Chas

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So one of the interesting things about the rack is that they used bronze bushings at the ends of the housing on which the rack gear slides. There is no discussion that I could find in the FSM's that talk about those bushings. I'm sure they're off the shelf items and are certainly replaceable with the right tools and replacement parts, but I'm guessing they were never intended to be a fixable item. If they're wallowed out, you're probably supposed to replace the whole steering rack assy? Note the lube groove cut in the bushing:

Those bushings shows as a replaceable item but don't appear to be available (on courtesyparts.com anyway). That grease looks pretty solid, do you think it was doing any lubricating?

Datsun 240Z/260Z/280Z Steering Gear (Rack & Pinion Type)

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Blue, Thanks for the leads. At this point, I'm 99% convinced that those rubber coated washers are indeed bump stops and my rack should never have had those plug bolts installed in the grease ports. Since the other end of that passageway is not plugged anyway, I'm thinking that it probably doesn't matter if I plug those holes with something headless (like set screws) or just leave them completely open hidden inside the rack bellows. But I AM sure those headed bolts are a mistake.

Zed Head, Thanks for the info on those bushings. Apparently they seem to have been available at some point. Curious thought that a part that was offered wasn't discussed in the FSMs. I bet they didn't sell a lot of them. And about that grease... Yes, that's what snowballed this project. Originally I was working on the rack mounting bushings. During that work, I noticed that the bellows were split so I pulled them off. Once the bellows were off, I noticed how hard and waxy the grease was on the rack ends. And before I knew it, I had the whole thing taken apart!

Chas, My inner tie rods droop when they don't have the spring and seat pushing against them from the rear. Are you saying that yours drooped even WITH the spring and seat applying pressure on the back side of the ball? If that's the case, then yours were clearly looser than mine. Mine stay up (as you pointed out) when attached to the rack, but once removed, they droop. When you cut your welds, did you use the cutting disk along the seam? Is that how you broke the bond? With a small slit along the existing part line? How much of an additional rotation do you think you got out of yours before they tightened up to spec? Eighth of a turn maybe?

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And here's progress to today. I got the entire thing torn down.

Here's a pic of the whole thing exploded. Only thing you can't see is the lower pinion bearing. I pulled it out, cleaned it, and put it back in before I thought to take this shot. And I wasn't going to pull it again just for the camera:

P1050368_zpsb54defa7.jpg

Left end parts:

P1050369_zps1c7bd13a.jpg

Right end parts:

P1050370_zpsa3f6b3d6.jpg

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Chas, My inner tie rods droop when they don't have the spring and seat pushing against them from the rear. Are you saying that yours drooped even WITH the spring and seat applying pressure on the back side of the ball? If that's the case, then yours were clearly looser than mine. Mine stay up (as you pointed out) when attached to the rack, but once removed, they droop. When you cut your welds, did you use the cutting disk along the seam? Is that how you broke the bond? With a small slit along the existing part line? How much of an additional rotation do you think you got out of yours before they tightened up to spec? Eighth of a turn maybe?

I had one side that was loose before I started dismantling it. The square nut (aluminium colour in your photo's) was tight, but the welded nut turned. I think the nut was not tight enough before welding.

I used a very small dremel drill with a thin cutting disc, about 1/2mm thick and cut between the nut and cap end until I was through the weld. The nut tightened about 1/3 of a turn past the weld. The other side was tight and didn't need dismantling at the weld.

Chas

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Thanks again Chas for the details. It sounds like your one side was definitely looser than either of mine. I don't think I'm going to whip out the Dremel at this juncture.

My rack bushing install screw-up by my PO is just the tip of the iceberg. I've found so much stuff wrong with my suspension it's just comical. I'm betting that my car will feel so much better when I'm done that I won't have a second thought about tightening up those inner tie rod ends.

That's the plan anyway!

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I have wondered for years if there was a cheap alternative. What did you discover? I have wondered if it might be possible to slather (this would not look nice) (isn't slather a nice word?) black silicone rubber all over an existing one with holes.

Edited by Mikes Z car
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Captain,

Really nice job of writing this up. I only wish I had it about 6 months ago when I was planning my rebuild. It would have been very helpful. Hopefully I can add a few more bits of information that will help as well.

I finished my rack refurbish and install just recently. I was planning to do this some time back but could not locate some of the critical replacement parts like the inner tie rod ends. I did find a source but they were not available at the time. So I went with a remanufactured one for about $300, which in the limit looked like it was only cleaned up, repainted, new boots, perhaps new grease, and that's about it. Was a definite improvement over my original one with 150+ miles on it and almost 40 years, but it was not what I was expecting.

In the course of doing some research, I ran across a rebuild article on the IZCC site:

the Z Car Home Page

It was contributed by John Downing and apparently those inner rack end bushings were available from Nissan at one point. If you read the article he purchased a "kit" that included these as well as some other critical components. Unfortunately I could locate them and they are NLA from Nissan now. Never the less, the article was very informative otherwise.

I gave up on finding the end bushings and decided to replace as much else on my original rack as possible. Went through the exact same process as you outlined in your posts, but I also found that my inner tie rod ends did droop even when full tightened, so finding new ones was going to be critical.

Well I did locate them, and although the design is a little different, they have proven to work really well so far. They are made by a company called Rare Parts and you can find the Z steering parts here:

http://shop.rareparts.com/smtp/shopdisplaycategories.asp?iyear=1974&imake=0041|NISSAN&imodel=1009|260Z&iproduct=0049|STEERING, GEAR, PUMP & COMPONENTS

These are a completely sealed unit but fit perfectly on my rack. They only make one thread configuration so you have to make sure you get the correct outer tie rod ends, and I believe it is the one for the passenger side.

In addition, I was able to locate the bushing / grease seal that is on the top of the pinion cover plate. If anyone needs the part number for that I'm sure I can dig it up.

Also, I went and looked at some of the pictures I took and I did not have any sort of plugs in the end of the rack. They were just open holes.

All of the gears and bearings looked good and so I cleaned everything up, re-greased everything and then re-greased it again, and installed it on the car. The new inners seemed to make a lot of difference and overall the steering was much more stable and responsive than the remanufactured one it replaced. So far very happy with the refurbish. Wish I could have found a new one, but in the absence of that, this was a very acceptable alternative.

I've included a few pictures as well.

Mike.

[ATTACH=CONFIG]69921[/ATTACH]

[ATTACH=CONFIG]69922[/ATTACH]

[ATTACH=CONFIG]69923[/ATTACH]

[ATTACH=CONFIG]69924[/ATTACH]

[ATTACH=CONFIG]69925[/ATTACH]

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Mike, Thanks much for adding to the info.

So it seems there might be a source for inner tie rods after all? I'm planning to reuse mine, but maybe I should squirrel away a pair for the future. That's great detective work.

I couldn't see your pic attachments though... Not sure what the problem is, but it's probably at my end. I'm going to post the last of my pics in a sec, and I sure hope you didn't just post the same shots!

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Here's some pics of the pinion gear bearings. There are two of them, and on the later racks like mine, they are identical. I've done a little digging and I believe the earlier racks used just one roller bearing at the top, and a sleeve bearing down inside the rack housing. But I've got two roller bearings. Here's the top bearing which is pressed onto the pinion gear shaft:

P1050348_zpsb2f38071.jpg

The bearings they used are intended to be side loaded, and because of the design, you can take them apart. Carefully pry off the grease seal, pop off the retaining ring, and the bearing falls apart. You don't HAVE to take it apart to clean it out, but you can do a more thorough job if you do. Here's the retaining ring popped out of it's groove:

P1050349_zps8f8e2ae4.jpg

Take the bearing apart, clean the old grease out, put it back together, and add new grease:

P1050350_zps5c9f7a3b.jpg

Here's the lower pinion bearing popped out of the housing. Note that this was not the easiest part of the job:

P1050324_zpse98bb220.jpg

But after seeing the grease in there, I'm glad I went through the effort:

P1050325_zpscd548b51.jpg

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I have wondered for years if there was a cheap alternative. What did you discover?

I'll post more info in a day or two. I want to make sure they fit as well as they I think they will. I want to give it another day apart in case anyone wants any pics of stuff that I haven't taken already.

I will tease you a little bit and tell you that I got a pair of them for $8.99 each, and they look perfect! :tapemouth

So... Anyone want to see any other angles of the rack or it's parts before I put this thing back together?

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