Steering play

[Otter74]

I’ve got this play in my steering that’s been there a while:

https://youtube.com/shorts/lU9JKjMlPXk?si=0C0z97KCScqqZTYO

If I Jack the front end up and turn the steering wheel or push on the wheels, it’s silent. There’s no play in the U joint in the smuggler’s box and the noise is definitely coming from below. This would seem to leave either the coupler or lash in the rack and pinion itself. I did have the cover off once and there appear to be no issues with the rack attachment to the car.



So…what is likely? The steering was rebuilt by the PO probably 40k miles ago and the coupler was new then. I don’t think that would cause the noise I’m getting but I’m not sure where all that lash would come from.

[Otter74]

Edit: if I turn the wheels to the right I can just barely both reach the steering wheel with one hand and put a hand on the left toe rod with another. The inner end of the tie rod is moving forward and down, seemingly more or less on the axis of the steering shaft. I can put my hand over the boot and the whole thing is moving. No axial play. Which suggests…a rack mount is loose? Bad bearing? When I had the cover plate off to replace the fuel pump the rack mounts looked fine and this noise was present then (it’s been there a while). I can hear it occasionally as a clunk on single-wheel bumps. Explains my slightly odd turn-in feel too.

It would seem to suggest a bad bushing between the rack and the rack housing

[john walker's workshop]

Sometimes the circular retaining clip on each end of the rack pops out, then the bushing follows it out.

[Otter74]

Originally Posted by john walker's workshop

Sometimes the circular retaining clip on each end of the rack pops out, then the bushing follows it out.

Is a bushing issue a safety issue or just annoying play? Looking at how it’s put together I can’t see any critical failure point if the hushing is bad

[Otter74]

Managed to borrow my neighbor to turn the wheel while I buried my hand into the hidey hole to feel the rack and housing through the boot. The whole rack is moving within the housing (both sides), so I am pretty sure the play has to be in the bushings between the housing and the tie rod. Direction of movement is what I would expect based on forces on the rack from the pinion gear. I’m not sure how it happened but at least it didn’t just show up.

[john walker's workshop]

The bushings are sleeves that insert into each end of the R&P assembly and support the sliding rack bar. The ones I've seen that came out had the retaining ring damaged because whoever installed the turbo tie rods didn't use the thick washers at the rack to keep the inner end of the tie rod from beating on the retaining ring on lock to lock turns. May or may not be your issue. Look under the rack boots.

[Otter74]

Thanks, John. I’ll look under the boots after I get back home. Suspect that’s what’s happened to mine. I just put 7s and 8s on the car and with a touch more width on the inside (IIRC) I noticed witness marks from full left lock on the left inner fender well. Suspect rack limit is off for reason you gave above.

[Otter74]

Does one of ya’ll know the part numbers for this bushing and its retaining ring? I can’t find it on the PET.

[Otter74]

Since winter is here and I had other priorities for the little late-fall wrenching time I had, the 911 is going to sit until spring, when I can take care of this, replace the starter and fix the odometer gears that broke on my way home in October.

Apparently there is no part number for this bushing. What's more likely - that the bushing broke apart and needs replacing, or that is came out due to lack of retention and just needs the snap ring and the washer that John mentioned? And if it needs replacement, does anyone have dimensions so that I can have one made? I'm sure it's got to be available somewhere but it'll take some doing for me to figure out where.

[E Sully]

In this thread here found wear in the rack, Post 3.
https://forums.pelicanparts.com/porsche-911-technical-forum/1166505-steering-box-rack-advice-please.html

Another good thread:
https://forums.pelicanparts.com/porsche-911-technical-forum/224112-sc-steering-rack-diy-bearing-replace.html

A video on the 911 steering rack.
https://youtu.be/kjg82Gv_-Go?si=6JNC9HCyJ5KWVvaQ

[mike sampsel]

Originally Posted by E Sully

In this thread here found wear in the rack, Post 3.
https://youtu.be/kjg82Gv_-Go?si=6JNC9HCyJ5KWVvaQ
Another good thread:
https://forums.pelicanparts.com/porsche-911-technical-forum/224112-sc-steering-rack-diy-bearing-replace.html
A video on the 911 steering rack.
https://forums.pelicanparts.com/porsche-911-technical-forum/1166505-steering-box-rack-advice-please.html

Ed,

FYI

I could not find a video in the third post above.

[E Sully]

I pasted in the wrong order, sorry.

[Otter74]

Thanks for those links - I'll check them out.

[Otter74]

I finally got to looking at the steering this afternoon. This is what the left end of my rack housing looks like:



This is where the play in my steering is coming from (per earlier in the thread, I could feel it with my hand here) and also the occasional clunk over left-wheel bumps. This is where the bushing and retainers shown here (nos. 17-19) are supposed to be:




I haven’t pulled the boot all the way back but I don’t feel anything floating around in there. I haven’t pulled the boot off the other side for visual comparison since I don’t want to make extra work for myself.

This is what I think should be visible:
https://forums.pelicanparts.com/porsche-911-technical-forum/1155791-steering-rack-side-bushing-help.html#post12186787

Per this:
https://forums.pelicanparts.com/porsche-911-technical-forum/1117749-steering-rack-silentblock.html

Someone did at one time machine some replacements:
https://forums.pelicanparts.com/porsche-911-technical-forum/1123706-these-steering-rack-parts-available.html

Apparently this McMaster-Carr part is suitable for the star nut:
https://www.mcmaster.com/90635A415/

And this is either part $18 or a bunch of these can be stacked for the bushing? I’m not clear:
https://www.mcmaster.com/4061T241/

Someone else apparently machined themselves a pair of bushings:

https://forums.pelicanparts.com/porsche-911-technical-forum/1140702-steering-rack-et-al-yet-again.html

So, I have questions. I do not have access to machining equipment or a machinist, unfortunately. Possibly a friend of mine could do it on his lathe.

Can one of you confirm that this is Not Right?

Does anyone have specs for the bushing for machining one?

Any other potential sources for a replacement? I saw a post where someone mentioned that a team called Red Dog Racing has made some, but that doesn’t seem like a viable option at the moment.

Can I remove the inner tie rod with the rack in the car, or is it going to have to come out?

The car has been like this for quite some time, but it’s not something I’d like to leave as it is any longer than I have to now that I know what the problem is.

[Otter74]

Well my friend offered to machine a pair for me out of Delrin or Oilite, so now I’m trying to track down dimensional data. Original construction appears to be sleeve with a stepped collar in the middle and square rubber o rings go on either end. McMaster-Carr part referenced above seems to substitute for rubber o rings when doubled up. Not sure why that construction is needed - just machine sleeve with OD, ID, depth?

Looks to me like 2~21mm length, 30mm ID, 33mm OD stepped up to 40mm OD for middle third, McMaster Carr O-rings go on 2x on each end. Tho why not just one piece of say Delrin. .002” press fit?

Edit: found dimensional info in this thread:
https://forums.pelicanparts.com/porsche-911-technical-forum/1140702-steering-rack-et-al-yet-again.html

But why is the OD stepped the way it is? If fabbing new it seems reasonable to just machine OD of ends of bushing to ID of available O-rings from McMaster-Carr.

[zuch]

I can confirm the Mcmaster-Carr star nut replacement fits/works. Replaced mine last week.

[Otter74]

Great to know. Do you have any knowledge of how well that seal ring works?

I popped under the car for a few minutes before leaving for work this morning and pulled the boot back far enough to briefly set eyes on the bushing/sleeve, which had gone for a walk and was hanging out by the inner tie rod. This evening I'll try to fish it down the rack and see if it's in one piece.

If it is, I don't see why I can't keep it and replace seal rings as needed and the star nut. Thoughts? If I have to have one machined, I suppose it doesn't have to be exactly like original as long as critical dimensions are there.

Can the inner (Turbo) tie rod be removed (and reinstalled with correct torque) without removing the rack? I assume so but don't know what tools needed to do right. I don't want to make more work for myself than necessary so if I can remove tie rod, pull sleeve, put new rings on and new star nut and be done that would be awesome. Don't know how realistic that is.

[zuch]

Yes you can pull the inner tie rod and expose the end of the rack. You will need either the super thin 32mm wrench or a pipe wrench. Those star nuts are made for this kind of application (and is what was there from Porsche). I only have about 100 miles on mine but so far so good. My bushing wasn't out of the rack though. I took the old tie rods off to replace them and found the star nut (broken) in the boot. I installed the star nut with a piece of 30mm inside diameter thin wall pipe. It went in perfect on the first shot. I have a few of those star nuts left if you need a couple. Pm me.

[Otter74]

I spent some time under the car tonight looking at what was there and measuring things. Not surprisingly all parts were there, as there’s nowhere for them to go. The inner rubber ring was broken and was loose. The outer rubber ring was fine. The star ring was hiding out next to the rack stop at the inner tie rod and it’s awfully hard to fish it out with a pick but it appears to not even be broken, which makes it a mystery how this whole assembly came apart. I measured the rings with calipers so that I can find something from McMaster-Carr. They appear to be 40.25mm OD, 34mm ID, 7mm wide. Fit of the assembly to the rack housing is not important as only the rubber rings fit against it (the stepped section of the middle of the sleeve is a smaller diameter.) Critical dimensions all live on the sleeve and that is intact. So I think if I remove the inner tie rod put new rubber rings on the sleeve and use a new star “nut”, I should be good. New parts in, pack some more EP moly grease in there (how much should there be?)

I think 32mm is the size of a bottom bracket wrench for bikes and I’ve got one of those.

Do I need to take the outer tie rod end off the tie rod to get the boot off before I can remove the inner tie rod? Or can i just work it back along the tie rod? I’d rather not mess with the outer tie rod end.

Also, what’s the easiest way to separate the outer tie rod end? I tend to only use pickle forks when the old end is bad, since they destroy boots. I can sometimes separate the taper on a joint by beating on the steering arm sideways with a sledge, but sometimes that doesn’t work.

[zuch]

I use the harbor freight screw ball joint separator. No damage and no whacking required. I haven't tried it, but you shouldn't have to remove the outer tie rod.