I think I've found the source of my tramlining
#16
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I just replaced this U-joint on the bottom of the steering shaft last October. Not the easiest repair I have ever done (especially alone), but manageable.
One trick that I used, was to source some longer bolts that I temporarily held the rack up in place with. This allows you to line up the rack close to where it is supposed to be so that you can line up the splines on the new knuckle with the steering wheel shaft and the steering wheel rack itself. Just make sure the bolts are fully threaded, then tighten all of them up to where there is a little clearance between the knuckle and the splines on the steering rack. Then lift straight up on the rack. If you are off a tooth, you have to try again. Since I was by myself, I had to strap my steering wheel in place, then crawl under the car, line up everything, then stab into place. I got it right the first time, luckily. Make sure to install a centering bolt before you start all of this.
I wish I had thought of using a screw to hold open the knuckle so that it would slide onto the steering rack splines. I cut off an old chisel, and tapped the chisel into the slot on the work bench. Getting the small chisel part back out wasn't bad, but a screw would have taken 4 seconds....
Oh, and my "rag joint" further up the steering shaft was fine, and so was the u-joint near the fire-wall. The bottom one seems to get all the wear. It improved my overall steering precision 1000 percent.....a 1/8" change in steering wheel angle at speed actually steers the car somewhere, instead of bumping it back and forth trying to keep it in my lane.....
One trick that I used, was to source some longer bolts that I temporarily held the rack up in place with. This allows you to line up the rack close to where it is supposed to be so that you can line up the splines on the new knuckle with the steering wheel shaft and the steering wheel rack itself. Just make sure the bolts are fully threaded, then tighten all of them up to where there is a little clearance between the knuckle and the splines on the steering rack. Then lift straight up on the rack. If you are off a tooth, you have to try again. Since I was by myself, I had to strap my steering wheel in place, then crawl under the car, line up everything, then stab into place. I got it right the first time, luckily. Make sure to install a centering bolt before you start all of this.
I wish I had thought of using a screw to hold open the knuckle so that it would slide onto the steering rack splines. I cut off an old chisel, and tapped the chisel into the slot on the work bench. Getting the small chisel part back out wasn't bad, but a screw would have taken 4 seconds....
Oh, and my "rag joint" further up the steering shaft was fine, and so was the u-joint near the fire-wall. The bottom one seems to get all the wear. It improved my overall steering precision 1000 percent.....a 1/8" change in steering wheel angle at speed actually steers the car somewhere, instead of bumping it back and forth trying to keep it in my lane.....
#17
Chronic Tool Dropper
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When disassembling, put index marks on the two shafts so the new joint goes back exactly where the old one sat. I use a marking pen, or sometimes a ***** punch or scratch awl if the shaft originality isn't precious.
Good idea on the longer bolts. Mine came apart for mm's before I had a lift, so the rack was supported by a scissors jack on blocks of wood as I worked to get everything lined up on reassembly.
Good idea on the longer bolts. Mine came apart for mm's before I had a lift, so the rack was supported by a scissors jack on blocks of wood as I worked to get everything lined up on reassembly.
#18
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Ugh, sounds like another "initiation" repair for a 928 owner. Oh well, I've made it through motor mounts, inside door handle replacement, timing belt, and assorted other repairs, why not another challenge? Thanks for all the tips, I'll be ordering the parts in due course.
#19
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Not too hard, this repair, very satisfying when the steering tightens-up.
The marking is smart, but dont' fret if you loose track of the marks during cleanup of the spines. Its pretty easy to eyeball and center the alignment of both of the shaft flats. I've never been off a single spline doing it that way.
The marking is smart, but dont' fret if you loose track of the marks during cleanup of the spines. Its pretty easy to eyeball and center the alignment of both of the shaft flats. I've never been off a single spline doing it that way.
#20
Chronic Tool Dropper
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It is possible to 'miss' the target position by plus-or-minus a spline, yet still be able to tap the pinch bolt back . Don't ask me how I know... Fromm then on, I put a wrap of tape around the shaft, a pen mar where the u-joint clamps splits, and mark the joint itself which end is up.
#21
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928sRus carry both the cover/protection cap (928 347 923 00) and the rubber doughnut further up the shaft.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."