w123 failed MOT on steering play - adjustable?

[Johnny G Pipe]

Good morning freinds.

The old girl knows she's changing hands...Having hardly been driven since breezing through her test a year ago, now she fails on emissions (a little misfire, suppressor cap I think), brake balance (pistons must be sticking), broken coil spring (eek) and excessive steering play (eeeek!). Fascists.

Anyway, I've not much ken about steering boxes - is this sort of thing adjustable, or is it new rack time?, which will doubtless be not the cheapest venture.

All help very much appreciated.

 

[jibcl500]

thats a shame, I had a very good W123 steering box on ebay for months but no one wanted it so I gave it to the scrap man.

jib

 

[television]

The box is adjusteble , the test can only be done with the engine running and the wheels straight ahead

 

[star]

Adsjust it, do it cold. on top of the bos is a 19mm nut and 6mm allen key hole threaded bolt, mark all items up in a line and loosen the nut, while holding the nut undo(anti clockwise) the allen bolt half to 3/4 of a turn amd tighten nut, try this you may have to do a couple of times, if too tight the steering will not self centre.


i hate typin

 

[Johnny G Pipe]

Thanks star, just found your reply. I'll give 'er a bash.
Bad typin sign of good mechanic, I erckon...

 

[stever]

You'll need a 19mm deep socket to release the allen nut adjuster - a standard socket won't fit. Halfords sell them if I recall. Be prepared to give it some welly - I think I had to smack a breaker bar with a lump hammer to free mine.

 

[robh]

Good morning freinds.

The old girl knows she's changing hands...Having hardly been driven since breezing through her test a year ago, now she fails on emissions (a little misfire, suppressor cap I think), brake balance (pistons must be sticking), broken coil spring (eek) and excessive steering play (eeeek!). Fascists.

Anyway, I've not much ken about steering boxes - is this sort of thing adjustable, or is it new rack time?, which will doubtless be not the cheapest venture.

All help very much appreciated.

Much wrong info given about adjustment. To bring sector into closer mesh with the worm ,tighten the allen head srew ,ie clockwise NOT ANTICLOCKWISE
as is so often and wrongly stated. 1/8th of a,turn at a time. Dont overdo it,
1" of pay at the wheel is ok.Remember most wear takes place when wheel is in the straight ahead position, so over tightening will cause binding and damage at full lock. (robh)

 

[star]

Much wrong info given about adjustment. To bring sector into closer mesh with the worm ,tighten the allen head srew ,ie clockwise NOT ANTICLOCKWISE
as is so often and wrongly stated. 1/8th of a,turn at a time. Dont overdo it,
1" of pay at the wheel is ok.Remember most wear takes place when wheel is in the straight ahead position, so over tightening will cause binding and damage at full lock. (robh)

Perhaps i've been doing it wrong for 25 years??? i dont think so but can be corrected.

 

[stever]

Much wrong info given about adjustment. To bring sector into closer mesh with the worm ,tighten the allen head srew ,ie clockwise NOT ANTICLOCKWISE
as is so often and wrongly stated. 1/8th of a,turn at a time. Dont overdo it,
1" of pay at the wheel is ok.Remember most wear takes place when wheel is in the straight ahead position, so over tightening will cause binding and damage at full lock. (robh)

This is simply wrong - the adjustment is most definitely anti-clockwise - i.e. opposite to normal tightening adjustment. Rest of advice about play and binding is sound though.

 

[star]

its true...... a little bit of knowledge IS dangerous.

 

[robh]

Sorry, but I tried the anticlockwise method. It made it worse. Clockwise did the job. This is strange! The recirculating ball type box (worm and sector) has been around a long time, and is used by many manufacturers. They are always adjusted clockwise to take up the free play. Why should MB be different. Looking at a sectional diagram in both Haynes and Peter Russek. There can only be one way to move the sector into the worm nut. Clockwise!
Please explain why this is not correct .

 

[robh]

Steering box riddle

My box failed to improve by turning the adjuster anticlockwise,so ignoring all the advice I turned it clockwise as I had done with other boxes and the freeplay was reduced. Recirculating ball steering boxes have been around a long time and are usd by many different manufacturers. They all work the same way. Why are other boxes adjusted clockwise yet as you say MB adjusts the oposite way.Beats me! Looking at the sectional drawing of the MB box in the Haynes and Peter Russeks manuals There is only one way in which the sector can be driven into the worn nut in order to take up the backlash and that's clockwise because of the slight bevelling (tapering) of the sector . I realise I seem to be the only one who thinks this so could someone kindly explain please.

 

[star]

My box failed to improve by turning the adjuster anticlockwise,so ignoring all the advice I turned it clockwise as I had done with other boxes and the freeplay was reduced. Recirculating ball steering boxes have been around a long time and are usd by many different manufacturers. They all work the same way. Why are other boxes adjusted clockwise yet as you say MB adjusts the oposite way.Beats me! Looking at the sectional drawing of the MB box in the Haynes and Peter Russeks manuals There is only one way in which the sector can be driven into the worn nut in order to take up the backlash and that's clockwise because of the slight bevelling (tapering) of the sector . I realise I seem to be the only one who thinks this so could someone kindly explain please.

Cant explain that, but I ALWAY adjust anti clockwise and it does the job, even told to do so by factory??

 

[robh]

The 'antclockwise to adjust' is strange advice, since every other manufacturers recirculating ball type box is adjusted clockwise to take up the slack. Why should MB be different? From the sectional diagrams in Haynes and Peter Russek (w123) there is clearly
only one way to bring the slightly beveled sector on the steering shaft further into mesh with the worm nut and that is through clockwise adjustment. It also increases torque,( so it says), but this I don't understand.
My own w123 box became worse when the screw was slackend off. Tightening (clockwise) reduced the Backlash (as logic suggested it would). Can anyone enlighten me on this matter, as there is no doubt the majority appear to disagree with me and my well intentioned advice shot down.

 

[MIW615]

I've never heard of adjusting anti-clockwise in order to reduce play, the basic design of a recirculating ball system consists of several parts contained in the steering gear housing. There is a worm gear on the end of the steering gear shaft, a cross (pitman) shaft is mounted in the housing in a position 90 degrees to the worm gear. So any adjustment has to be clockwise to reduce excessive play

 

[MIW615]

Forgot to post these pics..................

 

[stever]

The 'antclockwise to adjust' is strange advice, since every other manufacturers recirculating ball type box is adjusted clockwise to take up the slack. Why should MB be different? From the sectional diagrams in Haynes and Peter Russek (w123) there is clearly
only one way to bring the slightly beveled sector on the steering shaft further into mesh with the worm nut and that is through clockwise adjustment. It also increases torque,( so it says), but this I don't understand.
My own w123 box became worse when the screw was slackend off. Tightening (clockwise) reduced the Backlash (as logic suggested it would). Can anyone enlighten me on this matter, as there is no doubt the majority appear to disagree with me and my well intentioned advice shot down.

Can't explain the mechanics, but Mark Cosovich, W123 expert, told me that the adjustment is anti-clockwise. The slack in my steering was removed by adjusting anti-clockwise. And finally these MB instructions (http://handbook.w116.org/Chassis/46-480.pdf) also show that the adjustment is made anti-clockwise (they describe it as "to the left"). So it's anti-clockwise!

 

[kth286]

All

On subsequent W124 it is anticlockwise to INCREASE friction torque and clockwise to REDUCE friction torque.

 

[stever]

All

On subsequent W124 it is anticlockwise to INCREASE friction torque and clockwise to REDUCE friction torque.

Exactly the same as W123 and W116 then - I expect the steering boxes are all very similar.

 

[robh]

Thanks for your support MIW615. The sector is in fact based on an angle bevel gear.
This means that its teeth are tapered ie thicker around the p.c.d. at the top (as shown in your diagram) This means that when the adjuster is screwed in (clockwise) the thicker ends of the sectors teeth are moved into mesh with the worm nut thus taking up the backlash. At the same time, because a greater diameter of p.c.d. is now in contact, then a greater degree of torque (force times radius) is exerted when the steering wheel is turned. Easy?