Suspension diagnosis for w123 - Page 3 - PeachParts Mercedes-Benz Forum

vstech · #31 02-06-2011, 11:06 PM

Quote:

Originally Posted by Yak

I think your driver side UCA washer is installed backwards. The "dish" should be toward the rubber. Compare the L/R sides: pic 2 post 10 to pics 4 & 5 post 26.

That may let the UCA drift a bit on the torsion bar.

AWESOME CATCH YAK!!!!
I knew something looked odd. both are indeed backwards! likely letting the rubber move a lot! I'd order new rubber,and reverse the washers!

JHZR2 · #32 02-07-2011, 06:45 AM

Wow, great catch... Sounds like a plan. No pickle fork for this, puller instead, right?

Thanks!!!

toomany MBZ · #33 02-07-2011, 10:37 AM

If you're just going to rearrange the washers and/or replace the rubber bushings, jack up the car, remove the wheel, then lower the car down on the LCA, getting it as level as you can and proceed.

JHZR2 · #34 02-07-2011, 02:22 PM

Right, but in order to get that bakk joint removed, Ill need a special puller, right? If I was replacing the whole UCA, Id beat a pickle fork in there, but just to fix, Ill want to keep the joint in tact, so there is a special puller tool, right?

May have the opportunity to hit a harbor freight in delaware (tax free) soon, so want to get my tools straight given that Ive never done this before.

Thanks!

toomany MBZ · #35 02-07-2011, 03:06 PM

I must not be following you.

However as I understand it, you won't need to disturb any joint to properly get those torsion bar washers installed.

colincoon · #36 02-07-2011, 03:14 PM

I think you are getting the upper control arm and ball joint confused. The upper control arm is the entire piece, whereas the ball joint is just the movable pin on the end of it.

You do not need a special puller or press to remove the UCA, just unbolt it and pull it off. Rotate your washers and then put back together.

JHZR2 · #37 02-07-2011, 04:08 PM

OK, I was thinking that if I needed to pull it out, Id need to remove the ball joint that attaches it to the steering knuckle...

This one, I suppose, from the wiki:

But Im hearing that I can get both washers off and reversed via simply removing the bolt to the body, not this ball joint?

Thanks!

winmutt · #38 02-07-2011, 04:49 PM

Yes. You will need to pry the UCA off the bar. Not so easy. Highly unlikely this is the source of your problem.

Who did the alignment?

JHZR2 · #39 02-07-2011, 05:13 PM

A just tires shop...

I know, I know... But after the LCA bushing, the tires were in such bad shape I wasn't going to put good money after bad, and figured at minimum they would be another set of eyes.

They did turn down aligning the 85 300d once because of play...

funola · #40 02-07-2011, 05:41 PM

Quote:

Originally Posted by Yak

I think your driver side UCA washer is installed backwards. The "dish" should be toward the rubber. Compare the L/R sides: pic 2 post 10 to pics 4 & 5 post 26.

That may let the UCA drift a bit on the torsion bar.

I don't think so. They are correct as is in the pics. On the nut end, the washer dish faces towards the rubber, on the other end (the torsion bar end), the washer dish faces away from the rubber.

Did the tire wear start after the shop performed the alignment? I'd check the toe-in to make sure they didn't botch the job. Very easy if you have the tool.

Most times you can't tell from from a visual inspection if rubber bushings are worn. You have to pry on them and look for movement.

JHZR2 · #41 02-07-2011, 07:50 PM

I'll have to take some more pictures and inspect. It sure looks to me from the pics I took that they are different...

winmutt · #42 02-07-2011, 08:25 PM

Quote:

Originally Posted by JHZR2

A just tires shop...

This is probably the problem. If the eccentric bolt on the LCA is on the opposite side of where it is supposed to be, that could certainly cause the problem.

Yak · #43 02-07-2011, 10:06 PM

Go to the link I sent the other day and look at section 33-500. The orientation for the washers is at the bottom of page 3.

To fix the washers I'd recommend jacking up the car and put it on a jackstand, remove the tire (to get room to work), use your jack to lift the empty hub a little (remove some pressure off the UCA, but remember your other wheel is connected to the other end of the bar). Remove the bolt and washers from the tip of torsion bar, inspect the rubber, put the washers in the correct way (per the FSM), then reassemble. I couldn't tell from the pics if the rearward washer was correct or not, but I think it was. I don't think you even need to disconnect the UCA at all.

The only tools needed should be a jackstand, jack, tire iron and a 17 mm or other size wrench.

Don't be distracted by the eccentric bolt on the LCA, yet. Info on that is in 33-512, page 7. Yeah, yours is all the way to max camber but one thing at a time. If your car was tracking okay, don't mess with it unless you need to.

Yak · #44 02-07-2011, 10:18 PM

I checked the pics in the post again. I think it's only the front washer on the DS UCA that looks off (pic 2 post 10).

If I understand the geometry and the shape of the washers correctly, that could let your DS UCA slide maybe 4-8 mm forward during a left-turn which COULD let your steering knuckle overrotate and produce that funky out-kick of the wheel.

With the wheel straight ahead, try grabbing the DS UCA and tugging forward hard. Does it move? Or with the wheel kicked out from your left turn, can you push it backwards? If you get movement, I'm thinking that confirms the problem.

But - I'm not a mechanic and I'm only looking pics, so I could be wrong.

winmutt · #45 02-07-2011, 10:31 PM

Ill take some vegas odds on the LCA bearing.