I just finished putting in new OEM LCA's and all steering linkages. I had it aligned today and it feels amazing. The steering on center could be tighter but I'm not sure what was normal for these cars. It has new everything (tires, struts, etc). The steering box was rebuilt last year.

Just now on the steering box, I started bringing the allen socket depth setting down an 1/8 of a turn twice and the steering's center response got better each time on the test drive. I just don't want to over do it.

What should I look out for to know I've gone far enough or even might need to back it off?

 

Do some slalom/corners at low speed, 15-20 mph. After you turn let the wheel slide through your hands to return to center. If it's lazy to return or won't return fully to center it is too tight.

 

Correct, except no Slalom stuff needed, just drive around the block, 10 MPH or so, the steering wheel should pretty much, return to center, as you come out of a neighborhood type 90* turn. I'd check this FIRST, before making the adjustment, to be sure there are not other factors, affecting the designed in "Return To Center" of the steering system.

 

Go in very small increments as you are doing.. The screw should never feel tight or require excessive torque.

As long as it returns to center you are good. Go too tight & you can damage the box.

Remember it will never feel like a modern rack & pinion... I think about this every time I drive my car.

 

i dont think the function of it is to actually return the box to center.... more along the lines of adjusting or reducing the backlash in the gear to keep it from wandering while going down the road.

 

Correct, it's just very important NOT to lose that return to center. If you do, the box is too tight and will fail.

 

Thanks very much everyone. I noticed that after my alignment the return to center was "heavier" and slower. (-1 camber, 3/32 total toe (.2 deg)). After the adjustment it drags just a little back to center. I'll back it off a little and report back.

 

Ok, reporting back. Turns out my toe-in was twice too much (I did the calc from inches to degrees wrong). I backed it off a bit and then set out to understand and setup the "saginaw" steering box. This video really helped me see what was going on on. It's pretty simple.


Because the pitman (or sector) shaft gears that engage the steering piston are tapered, the "tighter" the pitman shaft is brought in, the more it can press, like a wedge, down on the sliding steering piston- causing the wear, locking, and slow return to center.

After being able to visualize what was going on, I was able to set the depth, just right by hand and eye.

Basically what I did was expose the rag joint, start the engine, and reach down and turn the rag joint a little from side to side and watched the moving end of the pitman arm. I tightened the arm in first, then backed it out until a tiny movement of the steering shaft did not move the pitman arm but a tiny bit more did.

The steering felt great after that.

Important Things:

1. Because the pitman arm gear teeth are wedged, if it gets overtightened, it may get wedged into the piston. So loosening the shaft adjustment screw might require a little jostling of the steering back and forth to break the wedged gear teeth. That's why its better to go too loose first and then bring it in tighter with 1/8" light turns.
2. Make sure to back the adjustment lock nut out enough so that you can move the adjustment screw easily in for some turns. I did not need to tighten the adjustment lock nut down until I was finished adjusting.