W123 ball joints... what else?
 

I'll be replacing the ball joint on my '85 300DT soon... been reading up on the excellent threads regarding proper tools, etc.

Are there any other bushings, etc that I should consider replacing during this procedure (i.e., what else is easily accessible during the disassembly/reassembly)? I'd rather not do an alignment after the procedure so probably won't replace tie rod ends, etc.

Depending on your finances, replace the upper control arms, lower control arm bushings and both track or guide rod bushings; front (on the LCA near the shock) and rear (at the body).

If you do replace these components, an alignment will be necessary.

Which of these affect alignement? Only the track and guide rod bushings? Do the upper control arms include the upper ball joint (ok... I'll search ;-)?

LCA bushings definitely affect alignment...either through wear or, when you replace them. Since you have to pull the LCAs to remove the lower ball joints, you may as well replace the LCA bushings (warning, none of these tasks are much, if any fun to perform).

The rear guide rod bushings can be reassembled to match the original settings before dissasembly but, if your guides were badly worn and had been adjusted to compensate, you'll need a full alignment. The front guide mount is too cheap to pass up replacement while you have the LCA off the car.

UCAs come as an assembly with upper ball joints and the bushings already installed.

I plan on keeping the car long term... so... I'll probably do quite a bit. Looks like I'll need an alignement. Perhaps a better question would be where's a good alingment shop in Portland, OR? MBI??

It is not necessary to remove the lower control arms on a W123 to replace the ball joints.

UCA inner bushings
 

upper ball joints look ok, so do outer bushings. Inners are done for. Is it worth replacing just the inner bushings?

If you are certain that the ball joint is okay, yes. I would replace the outer bushings in any case. They are cheap.

Says who? And, how many of these units have you pulled apart?

Enough to know that it is not necessary to remove the lower control arm to replace the lower ball joint on a W123. Sorry that you are confused. All that is necessary is to separate the ball joint stud from the LCA. The LCA can remain in place.
The MB Chassis Service Manual is in agreement with this position, stating that it is only necessary to remove the steering knuckle.

My mistake. Please accept my apologies; you're absolutely right, the steering knuckle must be removed in order to replace the ball joint.

I honestly don't know what I was thinking of since I just completed (2 weeks ago) a full rebuild (all the above mentioned components) of the front of my SDL and the 126 is practically a carbon copy of the 123 components. And, I don't have any left over parts - steering knuckles or LCAs either.:wacko:

Ball joints are a pain on a 123 or a 126 if you don't have the magic tool. I've done both cars without it (used generic tool instead). Really don't want to do that again too soon. Oh, and I managed to NOT replace one of the inner control arm bushings on the 123 (left and right sides were done at different times in different ways). Now I have to go back and replace the blasted one on the lower arm so I can get the car to align. All this on a car I'll probably scrap! Arrrgghhh!

For around $350+/- for the above mentioned parts + the price of ball joints (labor not added in), do it all at once & get the pain over with - :) Then, budget in the future for tie-rods, etc. & get many more miles out of your Benz! If budget is an issue, substitute Hamm's Light for your Molson habit for a few months & save up some green - :D

Reminds me of the people that need a water pump changed on a Honda, for example... you tell them, "Hey Mr Customer, while we're in there, we really should go ahead & change the timing belt; you'll pay the same labor again if I have to do it later instead of today... Okay, so you'd rather wait until later? Well, it's your money, and I'll be glad to take it again since you've opted to wait to do the timing belt in the future." :eek:

bnc

UCA Bushings DIY
 

Anyone know of or have a DIY on this? Didn't find anything on the DIY Forum suspension page.

Thanks,
Mark