Adjusting a Power Steering Box

[twistedtree]

I've got a lot of steering wheel slop, and the play appears to be in the steering box.  I just removed the lock nuts and disk cap over the adjusting bolt and replaced the o-ring to stop a leak, and now I'm trying to understand how to adjust it properly.  The BBB talks about adjustments of the manual steering box, but is silent about power steering.

I gather the bolt controls the load of a spring against some internal part of the steering gear?  Will adjusting it take any of the play out of the steering box?  And which direction do you turn the bolt to increase the spring load, and which way to lighten it?  And once adjusted, should the disk cap be tightened down until snug while holding the bolt so it doesn't rotate?

Thanks,

Peter

[ja17]

Hello Peter,

Make sure that the plastic bushings in the coupling  between the steering column and the steering box are good. Most often this is the source of most play.

[twistedtree]

I think the coupler is OK, or at least it's much less of a problem than the box itself.  With one hand rocking the steering wheel, and the other feeling the steering box side of the coupler, I can feel the coupler moving with the wheel, but there is no steering arm or front wheel movement.  I haven't measured it, but I'd say I've got 1-2" of movement at the steering wheel before the wheels start to turn.

[ashley]

Hi Pete
The play in my steering box turned out not to be the box, but a loose nut holding the pitman arm to the shaft. Love the easy fix, hope yours is likewise...Happy New Year
Eric

[twistedtree]

That would be nice - I'll check it out.

[Benz Dr.]

I believe you turn the screw out until the play is taken up. You can get it too far and the steering will go tight. If that's the case turn it back in a bit.
Thy can be rebuilt but 've never attempted to do one. I've had one ot two that we couldn't sort out so we replaced them with used ones and thy're still working right. The enemy of things like steering boxes is dirty oil. Keep that ATF changed out every few years and it will never give you any trouble.

[ja17]

Yes, quite complex. The section in the workshop manual for rebuilding the  steering box is around thirty (30) pages long! The rebuild kit has around 40 seals, o-rings and gaskets. Hard parts can be very pricey. And as Dan suggests, replacement with good used units are a good option.

[Miloslav Maun]

Sorry to open this old thread but I can't figure out which bolt to turn to adjust the steering box play.
I've removed the cap (red arrow on the first photo) and then loosen the contra nut (red arrow on the second photo). Then I tried to tighten the steering by truning the threaded shaft (using a 7mm wrench)(green arrow). I managed to turn it 1/2 a turn clockwise but it did not make any difference in the steering play. I  couldn't tighten it more, the resistance was big. So I tried to turn it 2 turns CCW and again no difference in the play. Then when I tried to put it back it seems to spin and I cannot find the tight end spot. Am I turning the right thing? Or should I actually tighten the plate with the two holes (yellow arrows). It won't move. I do not have any special tool, I just used circlip pliers and did not apply force.

Please advise.

[George Des]

There is a fairly involved process of trial and error using the two nuts, a torque wrench, a dial indicator and a pin spanner to set the adjustment properly on the steering shaft. You may want to see if you can get a copy of the power steering box repair section to view what is involved. Not too hard to do if you have the spanner, dial indicator and appropriate size torque wrenches, but you do need to follow the procedure to get it right. I've just broken down two boxes completely to clean them up and reseal. Lots of nitrile o-rings, teflon seals and little parts that need to be replaced and assembled in a set sequence. The Hungarian 113 site some have referenced on this Forum gives some idea of the full process. I've left this final adjustment on the two boxes I've worked until later when I have access to my complete set of tools.

[Miloslav Maun]

I do not plan to get inside of the box, I just thought it could be tightened a bit. But I'm note sure which bolt to turn...

[George Des]

The adjustment requires a combination of  correct torque on both the circular nut with the two holes and the rectangular bolt. Take a look at the M100 MB Forum. There is a discussion there on how one guy appro ches this.

[Miloslav Maun]

Can somebody send me the manual for steering box rebuild? I have the BBB but cannot find the section. Is it a separate manual?
muf@mail.cz
Thanks

[George Des]

There is a separate manual for this. Someone on eaby has been advertising them for about $20.00 or so.