steering column question:
On a 1968 Corvette steering system, there are three places where parts assemble together with splined shafts.
1. The flex coupling to the gear input shaft.
2. The flex coupling to the steering column shaft.
3. The steering column shaft to the steering wheel hub.
I would suggest that you rotate the gear input shaft full travel. That should be 3.6 revolutions. Come back from full lock (either direction) 1.8 revolutions. Your gear is now exactly on center.
At this point, the bolt that attaches the flex coupling to the gear box should be vertical with the head pointing straight up. So now your gear box is centered and your flex coupling is assembled correctly to it.
Your telescoping steering column should have a machined flat on the shaft that attaches to the flex coupling. That flat should be exactly at 12 o'clock.
Now when you assemble that steering column shaft (with the flat at 12 o'clock) to the flex coupling, the upper end of the steering column shaft should have an indentation also exactly at 12 o'clock. Matching the steering wheel hub (with its own indentation) to the steering shaft indentation should have everything centered.
Now this is how the whole system should be assembled to have everything exactly centered. Now comes the big HOOKER! All of the shaft splines, (i.e. gear input shaft, steering column lower shaft, and steering column upper shaft) had the splines machined randomly on the shafts. So it is possible to have each set of splines oriented slightly one way or the other. You may very well find that the flex coupling can be assembled to the gear input shaft (or to the steering column shaft) in two possible positions.
You may be able to balance the flex coupling position(s) and the steering wheel hub position so as to end up with everything centered.
Assuming your front wheel toe settings are correct, you can adjust the steering wheel centering by rotating the left and right tie rods. You will need to rotate the both tie rod adjuster tubes the exact same amount and the same direction to cause the steering wheel to move one direction or the other. By rotating the adjuster tubes the same direction and amounts, you will not change your original toe setting.
Otherwise, you will need to take your car to a good alignment shop and have them adjust the front end toe while holding the steering wheel at its 12 o'clock position.
Hope this helps,
Jim
let me tell you just a couple of more details....first of all, i have restored this car from a bare frame up, (total basket case that had already been disassemble) so my front end is not aligned at this point, i adjusted tie rods etc. (toe) so that wheels appear to be somewhat in alignement .....(eyeball alignment only) but was careful to have both tie rods adjusted the same, and if i re-call (been working on this car for 4 years now) i did check rotation left to right and center. so, i put flex coupler on steering column at 12 o'clock with wheels straight.
but, here is what i'm really confused about....the steering column is still out of the car, and while holding it, and rotating the wheel so that the flat on the lower shaft is at 12 o'clock, the steering wheel is at about 2 o'clock....(in other words, the problem seems to exist in the column itself) does that make sense? i did assemble the steering hub with indentation lined up with indentation on shaft, so one would think that the steering wheel would be at 12 o'clock when the flat on the lower shaft is at 12 o'clock also. what do you suppose is wrong, i haven't tried, but i would think moving the wheel over one bolt hole would put the steering wheel at about 11 o' clock?? any ideas? Rick
ps, i do realize that once i get the car to an alignment shop that they will have to do some tweeking to both front end adjustments, but i just want to make sure column is installed properly. thanks.....
I would say, with the column out of the car, place the machined flat on the end of the lower column shaft at 12 o'clock. Now place the steering wheel hub on the upper shaft as close as you can to being centered.
If you are one spline off, that won't hurt anything. Install the column into the car and let the alignment shop center the road wheels to the steering column by adjusting the tie rods.
One more comment. The location of the steering wheel hub to the steering column shaft also affects the turn signal switch cancelling feature. (The turn signal cancelling cam is located by the hub.) I do not think that one spline either way of center will cause you to notice that your right and left turn cancelling is different. Moving the hub several splines in either direction and you will begin to notice that one direction the turn signal cancels with just a twitch of the steering wheel, the other direction you would need to turn the steering wheel nearly 180 degrees to reach the cancelling point.
BTW, do me a favor and count the number of splines and the diameter on the upper steering shaft. I know that the male thread on the end of a telescoping steering shaft is 9/16-18.
Jim
Last edited by Jim Shea; Apr 25, 2013 at 09:42 PM. Reason: Affect of turn signal cancelling cam
I would say, with the column out of the car, place the machined flat on the end of the lower column shaft at 12 o'clock. Now place the steering wheel hub on the upper shaft as close as you can to being centered.
If you are one spline off, that won't hurt anything. Install the column into the car and let the alignment shop center the road wheels to the steering column by adjusting the tie rods.
One more comment. The location of the steering wheel hub to the steering column shaft also affects the turn signal switch cancelling feature. (The turn signal cancelling cam is located by the hub.) I do not think that one spline either way of center will cause you to notice that your right and left turn cancelling is different. Moving the hub several splines in either direction and you will begin to notice that one direction the turn signal cancels with just a twitch of the steering wheel, the other direction you would need to turn the steering wheel nearly 180 degrees to reach the cancelling point.
BTW, do me a favor and count the number of splines and the diameter on the upper steering shaft. I know that the male thread on the end of a telescoping steering shaft is 9/16-18.
Jim
Last edited by razman; Apr 28, 2013 at 04:51 AM. Reason: sp







