BC

I am confused. When I do this, I simply remove the steering wheel with the rack centering bolt in and put it back straight. Am I missing something?

SharkSkin

Dave, Brendan, I don't really know why this is. I do have some hearsay and my own observations & speculation to offer though:

The column locks in one of two positions. Neither position lined up with the input shaft while the centering bolt was in place. There is a flat cut in the input shaft that must be lined up with the pinch bolt(at least in my case). I have heard that some steering u-joints are designed with the pinch bolt further from the axis of the input shaft, these can be installed in any orientation since the pinch bolt will fit nicely in the shallow groove that runs 360° around the splined portion of the input shaft. The flat is cut much deeper than the groove. In this case, you can only choose between one or two positions that allow clearance for the pinch bolt -- e.g. "position A" or one spline offset from "position A". Later, I'll see if I can dig up a pic that helps illustrate this.

Dave, to your question: I have been unable to find a spec that stipulates what position the flat on the input shaft should go in. Maybe there isn't one outside of ZF? Or none that the rebuilders that we've dealt with know of?

Brendan, Maybe yours just hasn't been f'ed with, or you have that later style u-joint that I've heard of.

BTW, the shark's now leaking from the rear of the PS pump housing. At first I thought the random ATF was from when the rack spewed. Apparently not. I discovered this just before running off for a 4-day camping trip, and since then it has only dribbled a hand-sized puddle on the garage floor. $12.95 PS pump seal kit en route.

Bill Ball

Dave:

Each rack I have seen has come with that cut positioned in a different spot relative to center. It seems no attention is paid to that in assembling the rack during rebuilds.

SharkSkin

That was my impression from prior searches on the subject, Bill. Also, talking to Brian V., many(most?) 928s he sees do not have the column lined up to lock with the wheel vertical either. It seems that the S.O.P. is to slap it together, realize that the wheel is off center, then reposition the wheel on the column. Um, not *his* S.O.P., but others'.

Bill Ball

It seems the lock position on every other car I have owned was not centered either. Why did you care?

worf928

Because people named 'Dave' are more ****-retentive ... ummm... perfectionists... yeah, that's it.... than most.

Dave, your findings on input shaft orientation match my own. No one that knows the 'why' is telling.

The randomization of input shaft orientation during rebuild is most off-pissing when the steering wheel is airbag equipped. I, like Dave, opted to Dremel the input shaft to accept the pinch bolt so that everything was lined up correctly. I suspect though, that this means that the core will be considered unusable when the seals next let go.

On non-AB-equipped cars I've done the 'steering wheel trick.'

Neither method is to me acceptable. The damn rebuilt racks should come with the input shaft correctly oriented.

SharkSkin

Bill, no good reason -- just a perfectionist, as Dave says. I assume that it lined up that way when the car was new and that's the way I wanted it. A matter of taste. BTW, most if not all cars should have one column-lock position that orients the wheel straight up, with the ability to lock in other orientations as well.

I doubt that the core is unusable, the splined part is pinned to the input shaft itself and can be replaced without replacing the input shaft/pinion itself. IMHO, if it was really important to the rebuilders that we not dremel the input shaft, they would get the effing thing in the correct orientation in the first place.

Bill Ball

I assume it never lined up. Every car I've owned locked at about 30 degrees. Maybe you need to redo it at 30 degrees.

SharkSkin

Hey, it's not *your* fleet I'm trying to fit it in with... Seriously though, I can't account for your observations. I towed a lot of cars from the rear while working for AAA, and part of the procedure for that is to tie the wheel in the straight-ahead position and unlock the steering(so the lock doesn't break when hitting a large bump). Pretty much all of the cars that were fairly new and/or were assumed to have been unmolested(little old ladie's '75 caddie with 5K miles, etc.) locked straight-ahead.

Maybe the standard orientation for dump trucks is 30° -- which would explain a lot.

worf928

griffiths

We, Griffiths, get asked this question from time to time.

If we were to look at say 100 "OEM original" racks, by OEM original we mean racks that haver never been rebuilt, repaired or remanufacturd before, we would find that the orientation of the flat on the spline on the input shaft (pinion assembly or spool valve assembly perse) with respect to the location of the "center gear tooth" (relative to the centering indent on the shaft visible through the inspection hole in the LH side casting when the rack is "centered" in the housing) we would find that there is no consistency (all racks assembled the same way).

I imagine that the OE mfg of the rack and P felt that is was not important however "we" know it would have been a nice feature for R&R of the rack.

At Griffiths all of our 928 racks pinion to rack gear are indexed in the same manner as opposed to what the OE or other rebuilders may do. On top of the rack surrounding the input shaft or spline is an aluminum cap. The cap has a small triangle cast in it. The cap can be installed in 3 positions, or 120 degrees . We install the cap in the same position for all 928 racks we remanufacture.
When the rack shaft's centering indent is positioned so that it is visible in the inspection hole, we then insert the pinion into the assembly such that the flat on the pinion's spline is always indexed in a particular position. However what we do or how we supply the indexed rack may or maynot agree with the current position of your steering wheel shaft.

If all the 928's, with respect to the orientation of the of the pinion gear relative to the rack shaft's center tooth, had been built in the same manner...... believe me we would attempt to match it however "that was not how they made them".

So the only solution after R&R of the rack to align the steering wheel in a perfect horizontal is to simply R&R the steering wheel if needed. A PITA?
Little Pita !

SharkSkin

Unfortunately, there are a different number of splines on the wheel and on the rack input shaft, so just R&R-ing the wheel may not always be the answer(it wasn't in my case).

worf928

Thank you for the explanation. I suppose that its good to know that they are randomized from ZF.

See above. Column lock orientation. Airbags. Not to mention the constant airbag fault that can only be cleared with The Bosch Hammer if you happen to not get a connector completely re-connected.

Brett Matthews

Well, time for me to jump in again...

I've just found out my rebuilt rack [WAY past warrantee period], has a failed left bushing [internal]...Any news about the 'group buy' on bushings????

My front tires are wearing funny, and the alignment is supposed to be 'right', but the tracking of the steering isn't right as I drive, on 'rutted' or wallowed out roads, Rosy will do sudden pitches out of line! NOT cool! So I went looking, and there is up and down movement of the shaft in the housing...No fluid leaks though!

I'll finally have a reason to replace the MM.... MAYBE replace the pan gasket if it is leaking..

Sources of rack suppliers? Prices? Reliability? Thoughts?

Ron_H

Me too. I need a rack. Mine has mucho play and tramlines all over the road. *#%&$#&%$#!! Can I buy one for less money by purchasing with a group buy? It must have the internal bushings replaced though.