Play in steering shaft to steering box connection

[chrisd0729]

Chasing a loose steering/wandering/bumpsteer problem and I think I found it here. Check out the pic and video below. This is moving ONLY the steering shaft and NOT the tires. The steering wheel is turning in lock step with the saft so there's no play between the shaft and steering wheel.
Is this fixable through adjustment in the box or, is the box shot?

http://vid144.photobucket.com/albums/r181/chrisd0729/Bronco/A6699EB0-1F35-4B50-AD82-450D52B07155_zps2xsq82qi.mp4

 

[jckkys]

It looks normal. What looks like play is just the twist in the torsion bar. You won't see it with the engine running.

 

[chrisd0729]

It looks normal. What looks like play is just the twist in the torsion bar. You won't see it with the engine running.

Interesting, I'll try it while the engine is running.
I thought if the engine is not running, there should be very little (if any) play in the steering wheel or shaft before it affects the tires. I'm getting almost 1/8 to 1/4 turn of the steering wheel before it affects the steering box.

 

[jckkys]

Don't worry it effects the steering gear right away. What your doing is just, not moving the pitman arm. Twisting the torsion bar allows pressurized hydraulic fluid to push a piston that moves the pitman arm. When the pump isn't turning there's no hydraulic pressure.

 

[Viperwolf1]

Don't worry it effects the steering gear right away. What your doing is just, not moving the pitman arm. Twisting the torsion bar allows pressurized hydraulic fluid to push a piston that moves the pitman arm. When the pump isn't turning there's no hydraulic pressure.

No. The input preload adjustment is loose. That allows the input stub to move in and out instead of transferring that movement to the pitman shaft during that duration of input. Torsion bar twist is only about 5 degrees in either direction and the steering wheel would return to center after pressure is removed from the torsion bar. It makes no difference if there is hydraulic pressure or not in this case.

It can be made better without removing the box. You need to remove the steering shaft from the input stub. Then mark the position of the adjuster plug (circular threaded part that the input stub is going through) in relation to the case. Then loosen the big 2 1/2" lock nut. The adjuster plug has two holes in the face for adjustment with a pin spanner. Turn the adj. plug CW to tighten until you feel it get snug, then turn it back about 3/4" on the edge. This removes all the slack in the input and preloads a couple Torrington bearings so don't tighten too much. Then you need to tighten the lock nut without adj. plug moving.

If you are not comfortable with this adjustment process I suggest having the box rebuilt by someone who knows what they are doing. It is possible to over-tighten the plug which could potentially cause the steering box to seize and kill you.

 

[chrisd0729]

Wow, great info! Definitely makes sense. I am nervous playing with something so easy to screw up, especially if I haven't done it before. Depending on the cost to rebuild the steering box (and if I can find someone local to do it), is it easier to simply replace the box with a new/rebuilt one? I looked around online and didn't have much luck finding one aside from Bronco shops (JBG, TBP, etc.). Surprisingly, Napa didn't even list one for my 77.

No. The input preload adjustment is loose. That allows the input stub to move in and out instead of transferring that movement to the pitman shaft during that duration of input. Torsion bar twist is only about 5 degrees in either direction and the steering wheel would return to center after pressure is removed from the torsion bar. It makes no difference if there is hydraulic pressure or not in this case.

It can be made better without removing the box. You need to remove the steering shaft from the input stub. Then mark the position of the adjuster plug (circular threaded part that the input stub is going through) in relation to the case. Then loosen the big 2 1/2" lock nut. The adjuster plug has two holes in the face for adjustment with a pin spanner. Turn the adj. plug CW to tighten until you feel it get snug, then turn it back about 3/4" on the edge. This removes all the slack in the input and preloads a couple Torrington bearings so don't tighten too much. Then you need to tighten the lock nut without adj. plug moving.

If you are not comfortable with this adjustment process I suggest having the box rebuilt by someone who knows what they are doing. It is possible to over-tighten the plug which could potentially cause the steering box to seize and kill you.

 

[Glass Pony]

Wow, great info! Definitely makes sense. I am nervous playing with something so easy to screw up, especially if I haven't done it before. Depending on the cost to rebuild the steering box (and if I can find someone local to do it), is it easier to simply replace the box with a new/rebuilt one? I looked around online and didn't have much luck finding one aside from Bronco shops (JBG, TBP, etc.). Surprisingly, Napa didn't even list one for my 77.

If you need a power steering box rebuilt just send it to West Texas Off Road.
I haven't heard of any bad experiences with them and I had a great service from them myself.


http://westtexasoffroad.homestead.com/files/RNRREVISED_ORDER_FORM.htm

 

[DuneBuster]

We went to West Texas Off-road for a rebuild. Pretty much fixed steering issues. Just replaced the rag joint with a Borgeson universal shaft, and that tightened steering more. Now steering at 70 on the freeways is not a wandering experience. One more note check the washers on the bolts for your steering box. If you use regular washers, they can cone in and loosen the box and your steering. So chose some thick Grade 8 washers.
Good luck!

 

[jckkys]

No.I hate to question Viper, but I see no in and out movement in the input shaft. There is also no reason to believe the wheel doesn't return to center when released. I tried doing the same L/R turn on my '77 and the same thing happens that I see on the video. With the engine running the pitman arm turns too. There may be some internal play but it wasn't much different when new.

 

[Apogee]

...which could potentially cause the steering box to seize and kill you.

Good explanation. I gotta say, I do hate it when my rig tries to kill me, but thankfully it has been unsuccessful so far and the assassination attempts have definitely reduced in their frequency since I bought her and started working out the kinks.

 

[Viperwolf1]

No.I hate to question Viper, but I see no in and out movement in the input shaft. There is also no reason to believe the wheel doesn't return to center when released. I tried doing the same L/R turn on my '77 and the same thing happens that I see on the video. With the engine running the pitman arm turns too. There may be some internal play but it wasn't much different when new.

You're not going to see the in and out movement at this scale. 1/4 turn of a ~20 tpi thread=~0.0125" Any in/out movement is a force that is not directed at turning the pitman. I can see the wheel not returning and that means it's not tight around the torsion bar due to this. Perhaps your '77 is a little loose also.

I had a long conversation with Tom Lee about 6 months ago and he told me this was a problem on new vehicles with Saginaw boxes ever since GM started using robots to assemble the boxes. I believe that was in the early '70s.

 

[muskrat]

Good thread. I bought a used PS gear box and without ever using it, sent it off to West Texas Off Road.

That was two years ago. I thought the box still had some slop in it, but it was hard to tell since i never used it before it was rebuilt.

Over the last two years, it got worse. I pulled it last night and put in a loaner box. Wow, what a difference.

So now, I need a new box or I need to get my existing box rebuilt. I'm gun shy getting the same box rebuilt since the last time I did, it didn't seem to make a difference.

I've read that most rebuilt boxes and folks that rebuild them, simply replace seals and such. Is this true? Does West Texas and other vendors check for backlash, play and replace gears and bearings as needed?

Need to know, cause i need to figure out what to do with my box.

Thanks for input.

Muskrat