W123 wagon handling, pretty poor after redone front end and rear subframe - PeachParts Mercedes-Benz Forum

degier · #1 03-26-2013, 07:27 PM

Hi peachy parts,

thanks to this wonderful forum I redid the whole front end of my 1984 300TD (non turbo) and the rear subframe. Invaluable good threads. Thanks to all.

I took everything apart, changed out all rubber bushings and mounts, links and rods, new steering damper and rebuilt steering housing, new balljoints and control arms. New bearings at the rear. And newer struts.
Last month I had a 4 wheel adjustment done.
In short; the lot!

The car doesn´t lean anymore and is way more quiet. Feels more "composed". Surprising how much reverberation (dash!) disappears with new bushings.

The wheel adjustment really helped getting the handling to a new level.
And here it comes; but still....

It can be hard work keeping the car centered on the road. Especially worn roads or even worse, with puddles.
Even a shallow puddle, on one side. yanks the car to one side. Scary at times.

None of my W123 wagons did this. All had worn steering housings, but were stable and reliable tanks. Still handling great on winding roads with fairly high speeds ( 110km/h 70mph).

Not this time. Having to correct my steering time and again, as if an external factor suddenly pushes the car to one side or the other. The steering feels non communicative and therefore I oversteer and have to correct that again.
Kind of, as if I became an old lady overnight...now where´s that mirror?

One note; I put stronger springs ( from a 300TDT) both on the front and the back so the car has a higher stance ( 1 1/2"), to deal with the bad gravel roads here in rural scandinavia. Also changed out the 15mm rear sway bar for a 17mm one.

I have two new Bilstein heavy duty front shocks, but not on the car as of yet.
The handling got better when I had more air in the tires ( of course, but I didn´t want to go back to the standard pressure)

Some thoughts:
-Rear subframe might have movement ( that might account for the weird changes in direction)
-Front sway bar is not as preloaded as before and results in wobbly handling ( but MB had north african 123s 2" higher than the euro models so...not sure that would affect it all so much)
- I can put back the wimpy springs on the front and install the HD Bilstein mofo´s just to check it out.

Has anyone experiences to share with handling on worn roads and or tips for getting the spirit of the car back in place?

cheers,

Jan.

t walgamuth · #2 03-26-2013, 08:32 PM

Two simple things can cause lack of straight line stability.....not enough caster, and toe out. Both are alignment issues. did the shop who did the four wheel alignment (see that right there raises a red flag since there is nothing on a 123 to adjust on the rear) use factory specs on the alignment?

The new shocks can't hurt. Are your tires good?

I don't know about raising the ride height, it cannot improve the stability I don't think but should not make a dramatic difference I would not think.

bricktron · #3 03-26-2013, 08:55 PM

alignment!!!

vstech · #4 03-26-2013, 09:19 PM

... you said you got the steering box centered... does it have much slack?

engatwork · #5 03-26-2013, 09:25 PM

I'd get another opinion on that alignment. Make sure they put the correct 123.xxx number in the computer.

sassparilla_kid · #6 03-27-2013, 12:42 AM

Needs more toe in

whunter · #7 03-27-2013, 02:54 AM

All of this is good advice/suggestions.

However, heavier/taller springs change the front and rear camber/caster = making the steering platform squirrelly (hypersensitive).

It would help diagnosis to have a precise list of what steering and suspension parts you replaced.

.

degier · #8 03-27-2013, 07:10 AM

Oi, thanks,

Some leads.
The questions to be answered:

The tires are 3yr old Continental 195 65 15 studded winter tires.

Here it is called a 4 wheel adjustment, I just copied the name. On the rear there´s eccentric bolts for the trailing arms that can be adjusted.

The total list of things, hold on;
I installed new:
tie rods
drag link and steering shock
ball joints
guide rod mounts and bushings to the LCA
LCA-frame bushings and eccentric bolts
upper control arms and bushings to the stabilizer bar.

steering box, rebuilt and centered, very little play if any. Cleaned out system, new filter, o rings and oil.

sway/stabilizer bar bushings front and rear
sway bar links rear
trailing arm bushings and eccentic bolts

sub frame mounts
differential mount
SLS struts ( newish) (cleaned out system and rebuild pump and valve)
shims for the springs, 14mm= max

To be installed:
HD Bilstein shocks front

Not done:
steering shaft coupling

The other stuff done is motor mounts, rebuild front brakes, new hard +rubber lines, new front disks, master brake cylinder, cleaned out tank and lines, new filters, rustwork all over and bilt humbert the underside, changed out one front light, trailer electrics repaired, new gaskets here n there, valve adjustment...bla di bla.

Much thanks to peaches, since I have never done this before. Nice to build up a skill sett like this.
And the car still looks like a banger, just how I want it

Jan.

whunter · #9 03-27-2013, 11:44 AM

Quote:

Originally Posted by degier

Oi, thanks,

Some leads.
The questions to be answered:

The tires are 3yr old Continental 195 65 15 studded winter tires.

Here it is called a 4 wheel adjustment, I just copied the name. On the rear there´s eccentric bolts for the trailing arms that can be adjusted.

The total list of things, hold on;
I installed new:
tie rods
drag link and steering shock
ball joints
guide rod mounts and bushings to the LCA
LCA-frame bushings and eccentric bolts
upper control arms and bushings to the stabilizer bar.

steering box, rebuilt and centered, very little play if any. Cleaned out system, new filter, o rings and oil.

sway/stabilizer bar bushings front and rear
sway bar links rear
trailing arm bushings and eccentic bolts

sub frame mounts
differential mount
SLS struts ( newish) (cleaned out system and rebuild pump and valve)
shims for the springs, 14mm= max

To be installed:
HD Bilstein shocks front

Not done:
steering shaft coupling

The other stuff done is motor mounts, rebuild front brakes, new hard +rubber lines, new front disks, master brake cylinder, cleaned out tank and lines, new filters, rustwork all over and bilt humbert the underside, changed out one front light, trailer electrics repaired, new gaskets here n there, valve adjustment...bla di bla.

Much thanks to peaches, since I have never done this before. Nice to build up a skill sett like this.
And the car still looks like a banger, just how I want it

Jan.

Did you get a print out of the 4 wheel adjustment ???

.

colincoon · #10 03-27-2013, 10:48 PM

Tires can also cause weird behavior steering wise. I just had mine aligned at MB a few months ago and it was still off a good bit. I figured I'd take it back the next weekend, but in the process I had my snow tires put on. Instantly changed to perfect alignment after doing so.

Stretch · #11 03-28-2013, 04:19 AM

I'm interested to know where you got the eccentric bushings (in Norway) for a W123. Link please - I've only ever seen them for sale on fastlane (and the shipping from the US kills deals for me)...

...If you have a skittish front end after raising the height of the front end my guess would be that the caster angle is set up incorrectly.

Although whunter has already asked for the data I'll ask again => what are the settings that have been made so far?

Another question =>

As you've rebuilt and refitted the steering box did you by any chance check the relative heights between the Pitman arm and the steering idler arm? They need to be pretty much bang on and there's a little bit of wiggle room there...

degier · #12 03-28-2013, 05:08 AM

Hi,

Yes I have the print out here. its in norwegian though, but you´ll recognize the numbers. If not I´ll translate more.
And I am honestly not sure if it is 123 specific. I am going to call him after easter to check that, as norway is on its ass untill tuesday.

Of course the adjustments were done after the new spring were installed. But sure, I am not sure all is well.

I am curious what will happens after I put on the summer tires, I am expecting some difference yes.

I did not check the relative height there Stretch. Where can I find the info? It just fitted ok I found.

Thanks,
Jan.

I pm you Stretch..

degier · #13 03-28-2013, 06:03 AM

Wow, hardly readable...even though it is 300dpi.

Hmm, ponder ponder...

degier · #14 03-28-2013, 06:09 AM

screenshots maybe;

Stretch · #15 03-28-2013, 06:22 AM

Well let's make the interesting one as big as possible

The problem you could be having is that the values used for adjustment are for a standard height vehicle. They might be different for a raised poor road height vehicle - there is mention of this option being available in the FSM but I don't have enough information to know for sure if the camber castor and toe was different for that suspension configuration...

...so I might be sending you off on a wild goose chase for that data.