Anyone ever rebuilt their steering rack and axles?
#1
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I just looked the parts up, the axles appear to be unavailable and I can buy a couple of 928's for the price of a rebuilt rack.
This is on an 88 S4.
Mine have torn boots all around and the rack is leaking.
This is on an 88 S4.
Mine have torn boots all around and the rack is leaking.
#4
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Rebuilt racks are readily available from 928 Int'l (http://928intl.com) for $395 (click on "Shop" then search for "steering rack"). Hard to find a decent 928 for that price
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If the axle boots are torn then dirt has gotten in and the CV joints are most likely toast. You can replace boots and regrease but they won't last.
Axles are available new but pricey, I believe that rebuilt axles come with new CV joints and are are readily available--
Search 928 Int'l for "928 332 033 44", that will bring up new ($837) and rebuilt ($249).
#6
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Edit: What Bilal said ^^^
Rebuilt racks are readily available from 928 Int'l (http://928intl.com) for $395 (click on "Shop" then search for "steering rack"). Hard to find a decent 928 for that price
:
If the axle boots are torn then dirt has gotten in and the CV joints are most likely toast. You can replace boots and regrease but they won't last.
Axles are available new but pricey, I believe that rebuilt axles come with new CV joints and are are readily available--
Search 928 Int'l for "928 332 033 44", that will bring up new ($837) and rebuilt ($249).
Rebuilt racks are readily available from 928 Int'l (http://928intl.com) for $395 (click on "Shop" then search for "steering rack"). Hard to find a decent 928 for that price
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
If the axle boots are torn then dirt has gotten in and the CV joints are most likely toast. You can replace boots and regrease but they won't last.
Axles are available new but pricey, I believe that rebuilt axles come with new CV joints and are are readily available--
Search 928 Int'l for "928 332 033 44", that will bring up new ($837) and rebuilt ($249).
#7
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check to see if any dirt has gotten in the joint and pitted the inside. if not, i would clean and re pack the joints and add new boots. plenty of people have re sealed the axles, i have done about a 4 cars worth.
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Alabbasi, you really need to check stuff out with Roger at 928sRus, he's just up the road from you.
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I rebuilt the steering rack on my '87 S4 a couple of years ago and haven't had a problem since. I bought a seal kit from Rennbay for $75 or so. 90% of the work was removing and reinstalling the rack assembly. The actual rebuild itself wasn't bad at all.
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Did you follow a DIY? I have a spare rack and the goodies to rebuild it. I was put off by the process to separate the rack without the proper tools. What did you use?
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There is a DIY on Rennbay's website, here: http://www.rennbay.com/psrsealkitfull.html
The problem is that most rack problems involve wear: either the internal bushings wear and the seals start leaking, or the internal bushings wear and the steering (and alignment) gets sloppy. The re-seal kits do not include new bushings.
There are two internal bushings: The passenger end has a simple plastic bushing, and the other end is supported by a "guide block" with a plastic saddle-shaped insert. Those are not included in the re-seal kits available here, but I have seen them in some kits from Europe.
The other bit of trickiness is that the guide block requires shimming. There is a spring and a shim under the plate (bottomside of the rack, as mounted). The spring is there to provide an illusion of tightness, while the shim actually sets the clearance between rack and pinion gear-- and locates the driver's end of the rack rod. I found a spec of 0.004" (0.1mm) for a similar ZF rack for a Volvo, that seems reasonable. But it is critical that there be clearance with no binding or additional drag over the full travel of the rack-- wear tends to occur more in the center, and if the pinion runs out of clearance off-center then the steering will bind, which is bad.
Edit: I used this tool to remove the collars at each end: http://www.sirtools.net/ ... ItemID/186/Default.aspx (Part# BMW3031 from SIR Tools)
The hammer and punch works but makes it a lot harder for the next guy with the proper tool...
This might also help. The drivers-side bushing consists of guide block #30, saddle-shaped plastic insert #30.1, and selected shim #33, and the pass-side plastic bushing is #24.
The problem is that most rack problems involve wear: either the internal bushings wear and the seals start leaking, or the internal bushings wear and the steering (and alignment) gets sloppy. The re-seal kits do not include new bushings.
There are two internal bushings: The passenger end has a simple plastic bushing, and the other end is supported by a "guide block" with a plastic saddle-shaped insert. Those are not included in the re-seal kits available here, but I have seen them in some kits from Europe.
The other bit of trickiness is that the guide block requires shimming. There is a spring and a shim under the plate (bottomside of the rack, as mounted). The spring is there to provide an illusion of tightness, while the shim actually sets the clearance between rack and pinion gear-- and locates the driver's end of the rack rod. I found a spec of 0.004" (0.1mm) for a similar ZF rack for a Volvo, that seems reasonable. But it is critical that there be clearance with no binding or additional drag over the full travel of the rack-- wear tends to occur more in the center, and if the pinion runs out of clearance off-center then the steering will bind, which is bad.
Edit: I used this tool to remove the collars at each end: http://www.sirtools.net/ ... ItemID/186/Default.aspx (Part# BMW3031 from SIR Tools)
The hammer and punch works but makes it a lot harder for the next guy with the proper tool...
This might also help. The drivers-side bushing consists of guide block #30, saddle-shaped plastic insert #30.1, and selected shim #33, and the pass-side plastic bushing is #24.
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Last edited by jcorenman; 07-29-2013 at 01:24 PM. Reason: Added info
#13
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I rebuilt a rack with a kit from ZF. The bushings and plastic parts Jim mentioned were all included. The seal kit was about 70 Euros and the work itself was not really complicated but you have to take your time and be EXTREMELY attentive to the details as some rings and washers look very similar or are oriented.
I took the rack apart and matched all parts of the new kit with the ones that came out. Check, double check and then check again. Thoroughness and cleanliness is crucial. It all has to go together smoohtly without any need for force.
For special tools you need a substantial 32mm wrench to remove the track rods (a 24mm wrench to counterhold the rack if I remember correctly) and a hook wrench to separate the central housing from the end brackets, that's all (I remember)
The rebuilt rack worked for many more years until wear of the rack and pinion caused excessive play and warranted a new rack.
Kurt
_____________
90 S4 Auto satin black metallic
I took the rack apart and matched all parts of the new kit with the ones that came out. Check, double check and then check again. Thoroughness and cleanliness is crucial. It all has to go together smoohtly without any need for force.
For special tools you need a substantial 32mm wrench to remove the track rods (a 24mm wrench to counterhold the rack if I remember correctly) and a hook wrench to separate the central housing from the end brackets, that's all (I remember)
The rebuilt rack worked for many more years until wear of the rack and pinion caused excessive play and warranted a new rack.
Kurt
_____________
90 S4 Auto satin black metallic
#14
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For now, I'm just doing research and trying to figure out my budget. For this reason, I'd rather not waste his time when the information is available on the forum and I'm not ready to order.
This is good news and the information that I was looking for. Thanks!
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Jim, do you still own the tool and would you be willing to loan it out?