W123 Front end rebuild guidance needed! - PeachParts Mercedes-Benz Forum

bgkast · #1 06-25-2008, 01:52 AM

I have been searching the forum for hours and have not found a good, complete procedure. I have the FSM CDs, Is there any better guide in the CD manual than 33-200: Removal and installation of front axel half?

The FSM procedure seems fairly straight forward, but only details the removal of the "axel" assembly as a unit (Upper and lower control arms, steering knuckle, guide rod), and not the R&R of the bushings or individual parts. Here is what I am still not clear on:

Removal of UCA/upper ball joint - Can I just use a standard ball joint puller (or a good whack on the end of the rod with a nut on the end of it to prevent it from mushrooming) to remove the old one, then just install the new ball joint/arm?

Inner LCA bushings – Can I just pry the old ones out, and install the new ones with "slide fluid" (ky?

) and a vice to press them in (making sure to properly align the "flat spots"?

Guide rod mounts - The rear mount seems to just thread on, but I am not clear on how the front mount to the LCA installs.

Lower ball joint – Again, can I use ball joint puller or the whack method to remove the ball joint from the LCA, then just take the steering knuckle to the dealer to have the old ball joint pressed out and new one pressed in?

I'll put a good wiki article together if I can figure it all out.

Thanks!

tarnbarn · #2 06-25-2008, 03:28 AM

Hi,

Quote:

Originally Posted by bgkast

Removal of UCA/upper ball joint - Can I just use a standard ball joint puller (or a good whack on the end of the rod with a nut on the end of it to prevent it from mushrooming) to remove the old one, then just install the new ball joint/arm?

Yes

Quote:

Originally Posted by bgkast

Inner LCA bushings – Can I just pry the old ones out, and install the new ones with "slide fluid" (ky?

) and a vice to press them in (making sure to properly align the "flat spots"?

Again, yes

Quote:

Originally Posted by bgkast

Guide rod mounts - The rear mount seems to just thread on, but I am not clear on how the front mount to the LCA installs.

The rod has to be refitted to the LCA before reinstalling. The mount is a rubber-steel combo that sandwiches it inside the LCA - it's very clear once you take it apart...

Quote:

Originally Posted by bgkast

Lower ball joint – Again, can I use ball joint puller or the whack method to remove the ball joint from the LCA, then just take the steering knuckle to the dealer to have the old ball joint pressed out and new one pressed in?

Absolutely.

I've gotta say that I don't agree that this info is not on the site - lots of people have written about this. Apart from the lower ball joint it's all very simple: undo, remove, replace, refit, tighten.
One tip I'd suggest is that you remove the hubs before yanking off the axle halves, as this sheds a heap of weight and makes removing and refitting a whole load more laidback.
Good luck with the rebuild - and the Search function!
Giles

dannym · #3 06-25-2008, 07:19 AM

I agree with the above answers.
The lower ball joint can be a PITA. I used a pickle fork but I had to grind down one of the prongs a little bit because it was hitting the steering knuckle.
It took a lot of hard hits with an 8lb sledge to break get it off.

Danny

lutzTD · #4 06-25-2008, 07:23 AM

for the inner lower there is some pressing depending on the style you buy. on the ones I installed i pressed the bushing together then peened the end of the inner tube while it was pressed to hold it all together so it would fit in the slot in the car.

mobetta · #5 06-25-2008, 08:31 AM

I also needed to peen the tube in the LCA bushings. I used a ball peen hammer and another 2 lb hammer to strike with. I beleive the 126 bushings are interchangeable, and an upgrade. I did not know this until I had ordered parts. silicon spray lube works fine, too.
I did use a HF ball joint tool to remove/install the bushings.

if you remove the hubs,(good idea) I used a few inches of 5/8 heater hose slipped on them to protect the threads.

good luck, and enjoy the "new" ride....a PITA job, but well worth it.

On a 500+mile RT this weekend, the wife looked over and caught me doing 90+MPH, on a crappy section of interstate around here- I didn't even realize I was going that fast, she road so smooth.( new front end, accumulators, and Michelins this year, new rear bushings and bil comforts all since I've had the car)

got 25.5 mpg's fully loaded and averaging 70 mph+

minimike1 · #6 06-25-2008, 09:04 AM

bg,
The whacking the ball joint with a bfh is an ok method to release the taper from the socket, BUT, you don't hit the tapered threaded bit with a nut on it like one might think.
the idea is to put a big pry bar at the bottom side of the ball joint like using a pickle fork, and whack the side of the housing that holds the taper. This temporarily destorts the housing and releases the taper. With the prying force of the pry bar or pickle fork, you take advantage of that tempory distortion and the ball joint pops out of the housing!

winmutt · #7 06-25-2008, 09:11 AM

Quote:

Originally Posted by bgkast

Removal of UCA/upper ball joint - Can I just use a standard ball joint puller (or a good whack on the end of the rod with a nut on the end of it to prevent it from mushrooming) to remove the old one, then just install the new ball joint/arm?

I have used a pickle fork to do this several times.

Quote:

Originally Posted by bgkast

Inner LCA bushings – Can I just pry the old ones out, and install the new ones with "slide fluid" (ky?

) and a vice to press them in (making sure to properly align the "flat spots"?

Yes. We pressed them with everything else still attached to the car using a very big long bolt and an impact wreench.

Quote:

Originally Posted by bgkast

Guide rod mounts - The rear mount seems to just thread on, but I am not clear on how the front mount to the LCA installs.

Its a bolt and some bushings

Quote:

Originally Posted by bgkast

Lower ball joint – Again, can I use ball joint puller or the whack method to remove the ball joint from the LCA, then just take the steering knuckle to the dealer to have the old ball joint pressed out and new one pressed in?

I used the ball joint tool kit from AutoZone to R&R the ball joint. Free rental. My balljoints were welded in so I would say its of decent enough quality. Just get creative with the different tools an use safety glasses

DeliveryValve · #8 06-25-2008, 10:45 AM

Roy posted this link/video in another thread. Shows a good way to pop the Ball joints off.

http://www.instructables.com/id/Splitting-an-auto-ball-joint-taper/

http://www.youtube.com/watch?v=tX7GVWcB-bg

If anything you should always avoid hitting down on the bolt end even with a nut on it. If a problem, jam in a pickle fork plus hammer pressure from the side of the taper eye socket.

bgkast · #9 06-25-2008, 10:59 AM

Thank you all for your replies. It seems like I did better in my information search than I thought.

The LCA bushings that I have are two pieces with a thin-wall tube inside them. I saw some info on the three-piece type that needs to be pressed together which was causing me some confusion.

I'm sure I'll have more questions as I get into the job.

Thanks again

winmutt · #10 06-25-2008, 11:04 AM

You still need to flare the 2 piece tube at the ends once the LCA is installed. I wish I could find a source on the three piece bushings.

winmutt · #11 06-25-2008, 03:43 PM

Here are some pics from my install :

http://winmutt.com/images/benz/springs/

http://winmutt.com/images/benz/P1020361.JPG (look in the parent dir for others from this)

Not totally useful but might give you some ideas about whats needed.
Here is the DIY:
http://winmutt.com/benz/diymbrepair/FrontSuspension/

For the ball joints, if you pack them with dry ice they will be much easier to pop and install. I HIGHLY recommend having some dry ice on hand JIC *before* you get started. The $3 or so it costs goes A LONG way.

Bajaman · #12 06-25-2008, 04:07 PM

To flare the tube I made a mandrel from two thick beveled "washers" in conjunction with a long bolt. Put the bushings in the LCA and press them in with a vice. Then flare the tube. I think that you could accomplish the same thing with two lug nuts on a long bolt (smaller than the lug nuts). The bevel on the lug nut will flare the tube as you tighten the bolt.

rrgrassi · #13 06-25-2008, 04:14 PM

How would/could you replace LCA bushings with the spring still in place?

Bajaman · #14 06-25-2008, 04:28 PM

I contemplated that, but in the end decided it wasn't worth the hassle. I suppose you could leave the wheel on the ground/ramp and put a floor jack directly under the joint while you remove the bolt. Slowly lower the end to where you can work on it. I really don't think you'll save much time or energy by the time you wrestle the new bushings in.

techguy512 · #15 06-25-2008, 05:32 PM

Quote:

Originally Posted by Bajaman

To flare the tube I made a mandrel from two thick beveled "washers" in conjunction with a long bolt.

I made a flare tool out of an old Craftsman 1/2 inch drive extension cut in half. The flare at the end of this particular extension was almost EXACTLY a match to the needed flare on the aluminum tube. Clamp in a vice and squeeze until the tube is flared. Cost was $6.