I have a 1971 corvette 454 that I am in the process of putting back together after a front end disassembly. My problem directly relates to the steering as it is not quite right and it’s bothering me.
I had a guy who is a retired aircraft engineer and does a lot of car work, overhaul the steering box as it had been dry for a long time and was worn out. I supplied him with a flaming river kit and he put the kit in and it seems fine. All of the steering components below the pitman arm have been disassembled and joints replaced as necessary and then painted and put back on the car.
I have set it up as per Jim Shea’s recommendations and have the mark at the top of the steering column aligned with the steering box having the input shaft with the flat at the 12 o’clock position which all looks correct.
With the steering wheel in the middle the front wheels are maybe 15 degrees off to the right and when turned to the left the stub axel hits on the stop on the A arm but when turned to the right the stub axel doesn’t touch the stop by 1/2 an inch. The pitman arm looks to be in the right position with the steering wheel in the straight ahead position.
The car has had some damage done to the left hand front which I have repaired as part of the process, also I am also not sure if it was like this before disassembly.
Could this be a steering box not being assembled correctly or is it merely a tie rod adjustment to correct the problem?
Any help would be greatly appreciated as it needs to be remedied before the brake master goes back in.
Thanks

 

If it's just tie rod adjustment, I would think the difference in length between them would be noticeable. How many turns do you have from lock to lock?

 

Depends on the gears.
The late 69-82 have a D-Flat on them, which should be at 12 o'clock driving straight. Almost all of these boxes from 63-82 are not dialed in on center. In your case you need to see where the Flat is compared to center & arm, most likely it is not the same.

Now the curveball, if you installed a new worm good luck. I have a new knockoff box here, new gears sold today, the flat is completely in the wrong spot, the box is junk, it will never dial in.

 

Tie rods look even enough and I think you’re right in that it would take a lot to correct the problem. Lock to lock is 3 and 1/4 turns.

 

So I think you might be right in that the flat on the input shat might not be in the right spot which would account for the problem. Next question is how do I correct it? I can’t alter the input shaft and the pitman arm is on a master spline so that’s fixed. I could adjust the steering wheel to suit? I am worried about the right turn not hitting the stop as it must be bottoming out on the steering box. I’ll check this. I’m about $800 Australian for the steering box already.

 

That's interesting, it should be 3 and 3/4 turns. You must be hitting the stop on the A arm before getting to the end on the steering box motion. Are you sure the pitman arm is on correctly? On my 78 you can only fit it at 90 degree increments, don't know if that's the same for a 71. GTR1999 is the expert, I'm sure he can help.

 

Yes I agree that is what it seems like it’s hitting the stop early and that extra movement needs to be on the other lock. I could try the pitman arm but I’m sure it wont work if i move it 90 degrees. Thanks for your help.

 

The more I look at it the more I think that the steering box is the problem and the input shaft should be one turn in or out. I’m not smart enough to work out which.

 

If new gears were used in the box, then all bets are off. As mentioned, the new vendor knock off box I have it has bad gears. The flat is no where close to where it should be and it will never be right. I won't grind in a 2nd flat either.

 

It is all new inside the box. Could it be that the box has been put back together wrong? What do I do from here? Thanks

 

The box with nothing on it should bottom out to the right and the left.
And the steering arms should hit the a-arm stop at the same time, once the tie rods are properly adjusted.

Now if that is centered and your key on the pitman arm is off, or the d-flat key on the steering shaft is off, you have a problem that will be challenging to solve.

The steering column shaft also needs to be centered for the turn signals to cancel properly.
There is the reason the factory uses all the keys and d-flats.

I hope there is some reasonable solution to your problem that gets you back to driving that 454!

 

Yes the box bottoms out either side with nothing on it. I’m sure I could fix it if the pitman arm wasn’t on a master spine which only leaves the steering box. If someone could let me know if it’s possible to get the pitman arm to move by adjusting the worm inside I might have a go at that. I can’t live with it as it is.Thanks for the help.

 

You won’t be able to adjust the worm. The worm has to be correctly preloaded.
Sector has to be machined to the original print which I doubt they are. The center is almost meaningless. Relationship between the center, high lash, and the arm position all have to be considered and correct. While I can’t say for sure without inspection I still think you have bad gears.
you can remove the box center it and see where the flat is. You should feel the drag snug up about 1/2 way through travel. A dial is not needed to check it but you should be able to see how close it is.
when the box is correctly built it will not have any play in the straight ahead position.
There is a lot more to this and there are things I do that is not in any manual plus I have the bushings made to my specs and size them.
If the high lash and arm are off which I suspect then you won’t get it dialed in.Depending on how far off the sector is off you might be able to mill a new set of splines but that’s not what I would do and I’m not recommending it.
If you still have the original gears they might be reusable many times the sector is still good but the worm is bad. Buying most new or rebuilt boxes today is not recommended. I still have the good gears but once they’re gone it may be the end of the line since I haven’t seen any good new gears yet. I grind in the flat with the gears I have.

 

Thinking a bit more about this, if you do have everything aligned as you say, then it seems that the input shaft has the flat ground on it 180 degrees out. The easy fix will be to remove the 2 bolts that go through the rag joint, rotate the input shaft 180 degrees (in the direction that straightens up the wheels) and put the 2 bolts back in. Actually not quite that easy as you might not be able to rotate the input shaft without moving the box or the column to get clearance.

 

I think you’re going to be right Gary. I’ll check the box in the morning but I’m fearing the worst. Can I send it to you to sort out given this method has failed miserably? Or can you just ship one to me?
Thanks for the advice

 

Thanks for the thought John but that still wont give me enough travel to the right. It’s really the pitman arm that’s in the wrong location and it is on a master spline. If Gary can send me one of his overhauled ones I think I’ll do that as I don’t want to keep throwing money at it. It’s expensive given the distance. I wish I was in America.
Thanks

 

I happen to have a pitman arm on my bench.
Since you are so far away perhaps some pics will help.
My car is a 72 and yours is a 71, so hopefully they were similar in this area?


My pitman arm has four keys in the threads. And some chiseled key marks. I aligned it 90* to the edge of my bench and to the eye, it does not point straight ahead. The centerlink ball joint is located slightly off-center. It is offset to the outside of the car, roughly 3/4" or so. It goes on with the curved portion pointing down. This one is currently upside down. The main shaft out of the box has the same 4 keys, cut as grooves. Unless all four keys on the box output shaft are cut off-spec, I do not see how this part can be installed incorrectly. But visually it just does not "look" correct, or "straight". I actually have 3 pitman arms, of 2 different parts numbers, and they all look basically the same from this direction.



My old dirty, grimey, leaky box from my 72. The INPUT shaft is all splines. It has no keys or flats at all, and could be installed in any position. Since this car has been re-assembled after an accident, I have no way of knowing if this is original to a 72, or what year it came from. But it does not have a d-flat, or a spline key, and a box like this may help you.



My new PS Borgeson box conversion has an entirely different input shaft. It has no splines at all, is very smooth, except for the large flat cut in it. I suppose this is the D-flat you and Gary are referring too? Actually this box has two d-flats. It looks to be close to horizontal when my box is centered. However the snug spot is just slightly off-center. Obviously I will have to do something non-original for the "rag" joint to connect this.

 

Leigh,
Your box is not an original box for your car, or someone installed the earlier worm. Most likely the box was swapped out. The rags have to match the input, 30 or 36 spline.

The pitman arms, #451 manual and #383 PS, were pretty much the same throughout the 63-82 run. The later C3 arms were slightly different in marking but otherwise they are the same. The sector spline indexing is what is off with the new gears and the D-Flats can be way off. Same with the Chinese D-Flat rags some come in with the flat off 180*

 

Please contact me directly for advice.

 

Unfortunately, that won't work. The Flat should be at high lash, it is unknown if that is true or not. Factory flats are and they are not on center., so it should be. The box in question has replacement gears, the flat can be anywhere. Case in point. I purchased the complete inventory of new gears from Tom Reina 14 year ago after he died. He had gears made as good as Saginaw gears. Those are what I have been using ever since. The D-Flat worms came in without the flat for most of them, until I found about 100 with the flats already ground in and all were wrong. I threw them all out as I was not going to grind in another flat in the correct position as I wouldn't trust them.

The column has a flat for the pinch bolt, The rag has a flat to mate to the input. They can only go on as shown. The box will never travel full distance, pt A to pt B, in the car, connected to the linkage.