w123 Steering Play and Ball Joints - PeachParts Mercedes-Benz Forum

New2MB · #1 10-01-2011, 10:59 AM

I just started driving and inspecting my 240D.

The first thing I noticed is that I can turn the steering wheel 3 to 4 inches side to side without effecting the direction of travel.

It seems that the steering shaft going into the steering gear box turns during that 3 to 4 inches but the output shaft of the steering gear box does not start turning until after the steering wheel has turned the initial 3 to 4 inches.

So the car must not have 124k as shown on the odometer for the gear box to be that worn out. I think it's ok to leave it as is, opinions?

In the process of inspecting that I also checked tie-rods which do not have any play in them.

I also checked the ball joints and found that the boots are torn all the way around and appear to have been that way for some time. The confusing part is that there doesn't seem to be any play in them and I am tempted to just reboot them considering the work that is required to replace the whole joint.

Maybe I am diagnosing them incorrectly? I jacked up the car and whacked the top and bottom of the tire with my other hand on the ball joint to see if it moves. They seem to be solid but am I doing this correctly? Other ball joints I have replaced (on Volvo's/VW's) have been very obvious that they are shot.

The boots on the upper joints are also split, can those be rebooted too?

Thanks in advance!

sixto · #2 10-01-2011, 11:30 AM

Confirm the coupling is good then read this http://www.peachparts.com/shopforum/diesel-discussion/303379-what-feeling-will-properly-adjusted-w123-w116-w126-power-steering-box.html before adjusting the box.

Sixto
87 300D

toomany MBZ · #3 10-01-2011, 11:38 AM

See the attachments.

Also, there is an adjustment on the box itself, an allen screw surrounded by a lock nut. Loosen the nut and turn the screw CCW a bit, this will tighten the steering.

New2MB · #4 10-01-2011, 12:35 PM

Excellent, I had no idea it is adjustable.

Thanks!

Stretch · #5 10-01-2011, 01:43 PM

Quote:

Originally Posted by New2MB

Excellent, I had no idea it is adjustable.

Thanks!

Be careful with that - follow the link sixto posted... I don't want to scare you - I just want you to go into a situation with your eyes wide open!

New2MB · #6 10-02-2011, 09:29 AM

I scrolled through that link, not seeing what it is you are referring to though, what do I need to be careful of with the adjustment?

Stretch · #7 10-02-2011, 12:54 PM

Quote:

Originally Posted by New2MB

I scrolled through that link, not seeing what it is you are referring to though, what do I need to be careful of with the adjustment?

There's two bits in there

1)

Quote:

Originally Posted by Army

Whilst I'll be covering most of the information in the chapters for resealing and adjusting the steering box in the FSM I encourage you to read through the chapters as well. Especially if:-
...

In the W123 FSM there are two chapters that are concerned with measuring the friction in the steering system. One is covered in the refurbishment of the steering box chapter 46-220 (which is the subject of this thread) and the other for measurement of the steering system fitted to the car with the wheels on the ground: This is chapter 46-120 which can be briefly summarised as wheels on ground, engine at idle => force required to turn steering on steering wheel nut should not exceed 5-7 Nm.

Please note chapter 46-120 is a check. It is only a check – not a method of adjustment. From comments on this forum I understand that adjusting the steering box play in accordance with the check procedure in 46-120 or just nipping up the adjustment screw is quite commonly done. Fair enough – but – before you do that please have a look at the final adjustment procedure at the end of this DIY... I have some extra information and a warning for you!

...

2)

Quote:

Originally Posted by Army

Now that the assembly is complete you are left to do the final adjustment.

Slacken the adjusting screw (turn clockwise when facing it) so that the output shaft can be easily rotated.

I recommend that you now take the time to wind the input shaft from stop to stop and make sure that the gearing feels smooth and that it does not bind (as the FSM puts it). You should be able to feel a slight change in stiffness in the centre of the travel of the output shaft.

To keep track of the travel of the output shaft I made some marks on a piece of masking tape showing the furthest points of travel and the centre position.

The FSM says to now measure the friction of the steering box. Place your balancing device back on the input shaft and measure the friction required to turn the output shaft (and thus the input shaft) beyond the centre position.

You are now meant to turn the adjusting screw in an anti-clockwise direction (when facing the screw) until the friction is increased by 40 – 60Ncm.

According to the FSM, in real terms this means that the amount of torque applied to the input shaft in order to move the output shaft beyond the centre position should be in the range of 110 – 160Ncm.

Warning – don't forget about the difference between Newton metres and Newton centimetres!

If you tighten the adjusting screw too far do not be tempted to just back it off a bit. That little amount of clearance at the end of the Pitman shaft / output shaft and the adjusting screw helps you to loose your place. I thought I could get away with doing this but I found that I couldn't. After working the steering from stop to stop I found that the friction changed slightly from the amount that I had previously set.

For this reason I recommend that you start all over again – tighten the adjusting screw until it is stiff to move and then repeat the adjustment process as detailed above.

I don't know this for sure but I think this might be the reason why some people have had trouble adjusting steering boxes by just nipping up the adjustment screw. If you decide to do this quick adjustment to your car I recommend that you only turn that pesky adjusting screw in an anti-clockwise direction!

Like I said before I don't want to scare you off - I just want you to know that you might make matters worse if you are not careful.

sixto · #8 10-02-2011, 01:01 PM

You can adjust by feel or adjust to spec as Army did. Adjusting by feel is a good way to wear out what's left of a steering box's life. As Army pointed out, it's not as cut and dry as adjusting to the point of no play then backing off, as some do with wheel bearings.

That said, it's a lot of work to take a very worn box apart for a simple adjustment. Back off the adjustment screw in eighth-of-a-turn increments keeping in mind that you don't want to go too far. An inch of steering wheel play will feel like heaven at this point. Note that adjustments should be made with the front wheels pointed straight ahead. It's normal, I was told, for more play with the wheels turned.

Sixto
87 300D

Zacharias · #9 10-03-2011, 04:12 PM

I was told that when you adjust by feel it should be done with the front wheels off the ground. Is that correct?

Stretch · #10 10-04-2011, 03:39 AM

Quote:

Originally Posted by Zacharias

I was told that when you adjust by feel it should be done with the front wheels off the ground. Is that correct?

The check detailed in chap 46-120 (W123 manual) says not. Have a look at point number 1 I posted previously for a brief summary.

sixto · #11 10-03-2011, 08:02 PM

I think you want a load on the box when you adjust by feel. With the wheels off the ground it'll be too easy to adjust past the point of having play. I'm no expert on this but I still think small adjustments followed by test drives is the way to go.

Sixto
87 300D