C1 steering box adjustment and alignment

[Troy P.]

I had someone who has been in the early Corvette restoration business for 55 years rebuild my steering. (With that experience I hesitate to call him Bubba) Gave him a $$ rebuild kit that included a new steering column shaft, new gears, etc. Now that I have the car back I see the steering wheel turns about 60 degrees from one direction to the other before getting any significant movement in the front wheels. Lets call this steering slop.

Obviously the steering box was not set up correctly. What adjustment(s) do I make, with the steering box and column in the car, to take the slop out?

Also with the tires straight ahead the steering wheel is turned 35 degrees from horizontal. So the first rule for a front end alignment (level steering wheel and lock it in place) was not followed.

If I level the steering wheel now and turn each tie rod tube the same amount on each side to get the tires straight ahead will that work? Or will I need a professional front end alignment done over?

[Frank D.]

Re: C1 steering box adjustment and alignment

I had someone who has been in the early Corvette restoration business for 55 years rebuild my steering. (With that experience I hesitate to call him Bubba) Gave him a $$ rebuild kit that included a new steering column shaft, new gears, etc. Now that I have the car back I see the steering wheel turns about 60 degrees from one direction to the other before getting any significant movement in the front wheels. Lets call this steering slop.

Obviously the steering box was not set up correctly. What adjustment(s) do I make, with the steering box and column in the car, to take the slop out?

Also with the tires straight ahead the steering wheel is turned 35 degrees from horizontal. So the first rule for a front end alignment (level steering wheel and lock it in place) was not followed.

If I level the steering wheel now and turn each tie rod tube the same amount on each side to get the tires straight ahead will that work? Or will I need a professional front end alignment done over?

We must have different definitions of "steering slop". I'd contact Gary Ramadei for some advice on how to check out that rebuilt box.
He walked me through troubleshooting my 63 box over the phone - one helluva nice guy....

[Troy P.]

Re: C1 steering box adjustment and alignment

Thank you Frank. Do you have Gary's phone number?

[Frank D.]

Re: C1 steering box adjustment and alignment

Thank you Frank. Do you have Gary's phone number?

I sent you a PM (Private Message)...

[Bob W.]

Re: C1 steering box adjustment and alignment

Troy, If you have a 53-62 servicing guide St-12 that should have a section on the adjustment of the steering box. If you don't have one you can buy one here at the NCRS store. look at page 3 under guides.

Bob

[Troy P.]

Re: C1 steering box adjustment and alignment

I have one but suspected it addressed setting the box up during a rebuild rather already installed in the car. But I will look and see if it addresses how to take the slop out.

[Richard M.]

Re: C1 steering box adjustment and alignment

The reproduction worm gear is the issue. The center of the reproduction worm is NOT the center of the steering wheel lock-to-lock position. Reproduction worms are not made to the same specs as originals.

When the rebuilder used the ST-12, he centered the steering wheel from lock-to-lock and then set the lash. This is the problem. When using the reproduction worm/shaft assembly, the rebuilder must find the center of the worm during the lash setup, THEN mark the end of the shaft. Then the lash adjustment can be made accurately. Unfortunately the instructions that come with the reproduction kits DO NOT explain this.

In order to properly set the lash now, first disconnect the Drag Link from the Pitman arm. Loosen the lash adjustment locknut/bolt. Have a helper slowly turn the wheel as you slowly bring in the lash to find center of the worm. Center of the worm will be highest resistance of the wheel with the same freeplay just off center in both directions just a bit off center. Work slowly as you don't want to tighten lash too far when the worm is off center.

When you find center, then bring the lash adjuster in so that there is a slight resistance. You can use a ounce weight scale as described in the ST-12. Then mark the end of the shaft. Reposition steering wheel at this point.

There is a very long drawn out story of how this was discovered in a PDF file in this Post. Details begin on page 43 of the PDF and will explain best. Page 30 and beyond also has some detailed info about the wheel lock-to-lock vs worm center issue. Note that this delta can vary in all repro worms.

Rich

[Troy P.]

Re: C1 steering box adjustment and alignment

Rich, I only understood about 1/3 of what you said but I treasure your input. Thank you so much.

Sounds like you have lead me or someone smarter/more mechanical than me to a solution that was impossible to find because the origin of the problem was not obvious.

I will have to study your process several times before I would attempt to make any changes. But I do have a few questions so far.

1. Will this solve both of my problems (steering wheel not level and slop in the steering)?
2. Will the front end need to be aligned after tightening the steering box?
3. Will the pitman arm need to be taken off and turned or just reconnected after the box tuning process?

[Gary R.]

Re: C1 steering box adjustment and alignment

Thank you Frank for the kind words.

While I do not rebuild the C1 boxes, (shipping and part costs are killer), what Rich mentions pertains to the C2-C3 box gears as well. This is not a new issue, every box I get in I first check it for preload, lash, and center. The original inputs have the chisel mark on them for 12 o'clock center position. This position has been mistaken for true center since the first 63 box hit the line and I suspect the same is true for the C1.

The fact of the matter is the steering marks are usually not on true center but high center, which is what Rich is referring to. So the marks are all over the place, most don't really know this, in fact some rebuilders have no clue. When replacing gears or swapping boxes the replacements generally do not line up in the same position and require tie rod adjustments. Many times the tie rod tubes are not going to be equal but many forget these were production built cars. The steering new was pretty darn good, the steering after some people or places work on them.... well lets say it's not the same.

What is worse is what I read on forums on how to adjust a box, it's plain wrong and if done may cause wear on the sector teeth faster then expected.

[Peter M.]

Re: C1 steering box adjustment and alignment

Troy,
Have a look at Joe Calcagno's web site "rarecorvettes.com". He has a series of how to videos detailing the overhaul of the C1 steering gears and I think he explains what Rich and Gary are saying.
I have not dealt with him but I have heard positive comments.
Kind Regards

[Troy P.]

Re: C1 steering box adjustment and alignment

Does this mean once I do the lash adjustment as described the next step would be to remove the steering wheel and align it level disregarding the center mark punched into the end of the shaft. Or is something more complicated involved in leveling the steering wheel?

[Richard M.]

Re: C1 steering box adjustment and alignment

Rich, I only understood about 1/3 of what you said but I treasure your input. Thank you so much.

Sounds like you have lead me or someone smarter/more mechanical than me to a solution that was impossible to find because the origin of the problem was not obvious.

I will have to study your process several times before I would attempt to make any changes. But I do have a few questions so far.

1. Will this solve both of my problems (steering wheel not level and slop in the steering)?
2. Will the front end need to be aligned after tightening the steering box?
3. Will the pitman arm need to be taken off and turned or just reconnected after the box tuning process?

Troy, Yes there is much to understand. We spent hours.... actually days, trying to figure out the problem with the new worm gears. We had no idea that the repro worm didn't match original center spec.

1. Will this solve both of my problems (steering wheel not level and slop in the steering)?

Yes. Once the worm is centered properly in the box the Pitman Arm will be in the as-designed position. The proper lash adjustment will then take out the free-play(slop) in the wheel. Again, as described in the PDF, the worm must be centered, then the steering wheel aligned to match original design. This is also why the reproduction shafts are not marked at the shaft end at the wheel with the 12:00 chisel strike. They are left unmarked. I mark it when I find center of the worm. The difference will be in the lock-to-lock turns on each side. Original worms will be equal at the wheel, repros will not. But this is okay because the steering stops in the knuckles would never allow full lock-to-lock at the wheel.

2. Will the front end need to be aligned after tightening the steering box?

This will depend on many factors. If the front wheels are perfectly straight when you put the box back on and not disturb them, realignment isn't necessary. However, after reassembly and adjustments of the lash then Drag Link, you won't know until driving the car if all is still straight underway. Trial and error adjustments of the Drag Link would correct it without need for a shop alignment. Just be sure there are plenty of threads held into the Drag Link tube after adjusting.

When the box goes back on the Drag Link should be adjusted with wheels straight. Because the worm wasn't centered, you couldn't get the Pitman Arm to mate to the Drag Link properly.This was your issue.

3. Will the pitman arm need to be taken off and turned or just reconnected after the box tuning process?

You don't need to remove the Pitman Arm from the box. The Pitman Arm is keyed to go on only one way when configured properly to mate to the Drag link. After the lash adjustment it can be recoonnected

BTW, if you have the Pitman Arm removed from the box, just be sure to use a wooden block against it to torque the nut when reinstalling. Don't torque with the worm/sector gears at it's internal stops as they could be damaged.

Rich

[Richard M.]

Re: C1 steering box adjustment and alignment

Does this mean once I do the lash adjustment as described the next step would be to remove the steering wheel and align it level disregarding the center mark punched into the end of the shaft. Or is something more complicated involved in leveling the steering wheel?

Troy as I was writing the previous reply I didn't see this.

Did you get the kit with the new worm/shaft assembly, ie the Deluxe kit? All of what I described is based on that....

It seems the rebuilder centered the wheel from equal lock-to-lock to set that chisel mark. This follows the ST-12 procedure on stock original worm/shaft assemblies. If so then it's in the wrong position. You'll have to re-mark it after using the worm centering procedure I described.

Rich

[Troy P.]

Re: C1 steering box adjustment and alignment

Yes I got the whole kit with new steering shaft with the gear already pressed on. I gather from your last post that the shaft did not have a centering mark like the OEM shafts.

One more question about setting the lash. As I turn the lash adjuster in and rotate the steering shaft am I looking for the point of least resistance to turning or the point of greatest resistance?

[Richard M.]

Re: C1 steering box adjustment and alignment

Troy,
Have a look at Joe Calcagno's web site "rarecorvettes.com". He has a series of how to videos detailing the overhaul of the C1 steering gears and I think he explains what Rich and Gary are saying.
I have not dealt with him but I have heard positive comments.
Kind Regards

Peter, The Part 8 Video outlines the lash adjustment. But..........

In Joe's example, the new shaft/worm assembly must be very close to original spec. The center of that worm is likely a match to original center spec. That is why he can get 2 1/4 turns each side of center on the wheel and have it match wheel center. As he describes, there is no chisel mark at the shaft until after he has found true center when doing the lash adjustment using the scale at the wheel.

In that PDF, 2 of us had 2 different kits from Corvette Central. His worm was offset in one direction, mine in the other direction. Because he followed ST-12 when he rebuilt the both, it created a error after assembly. he used the 2 1/4 turn centering procedure. This left him a Pitman to Drag link separation from stock. After he readjusted lash finding center of the worm, then his problem was solved.

Not all worms match original center spec. Joe told me this himself some time ago. Some will have more of a offset than others on either side. This is why if one uses a worm that is not to the same spec as original, using 2 1/4 turns wheel lock to lock as a centering guide is not accurate. The result is a offset Pitman arm to Drag Link and slop at center of the wheel.

Unless all new repro kits have changed ensuring the worm center matches original spec, I am unsure why Joe doesn't describe that in his videos.

Rich