Possible to Remove W124 Lower Control Arm Without Spring Compressor? - PeachParts Mercedes-Benz Forum

gmercoleza · #1 01-17-2007, 01:20 PM

I've been reading the W124 ball joint DIY: http://www.peachparts.com/Wikka/W124BallJoint

Look at this picture:

It looks like you could take a weightlifting bar and run it through the bottom hole in the LCA, through the spring, and out the top of the spring perch, leaving it sticking out about half a foot. Then you could lower the LCA very slowly until the tension on the spring is released. I would think a weightlifting bar or something similar like a thick rebar is much stronger than a chain and not going to get snapped in the event the spring dislodges.

david s poole · #2 01-17-2007, 01:38 PM

i agree it can be done but what are you trying to do? my shop is not that far from you and i have the benz spring compressor.call me,sat morns are usually free.

hanno · #3 01-17-2007, 04:48 PM

David, a most generous offer! I'll be in line when you move to the mid-Atlantic coast

gmercoleza · #4 01-18-2007, 09:19 AM

Thanks for the offer David, I may take you up on it just yet. But I found this thread last night:

Front Spring Removal - As I thought, simple without special compressor

Somehow I overlooked this thread in my previous searches. It looks like my idea can work after all and isn't exceedingly dangerous, as a few individuals have already done it before with no problem. I think I will use the free hook compressors from Autozone as a safety, but it would appear that the spring only has 3 or 4 inches of travel beyond the fully-extended position with the LCA hanging prior to disconnecting the strut, so at that point it is almost fully unloaded.

I am attempting to repair THIS. I will give it a try in a couple of weeks and will attempt to document with pics and a writeup. If I have to resort to a spring compressor you will hear from me.

a2t · #5 01-20-2007, 12:52 PM

i had a front spring break on my 87 300d, so it was not possible to use the mb spring compressor. the spring is like a locomotive spring, so i just brought it into shop and let them mess with it.

they had a few guys push up on control arm and remove bolts and lower the arm. This worked fine. What surprised me was they installed the new spring same way - had a few guys push up on the control arm to get bolts back in place.

So...it is possible and it was done on my car.

Would I have been the one doing the work? HELL no, and there isnt much I'll let a shop do for me.

gmercoleza · #6 01-26-2007, 10:32 PM

SUCCESS! Well I just removed the control arm successfully WITHOUT a spring compressor. It was so easy I'm actually quite amazed. I don't think doing so was dangerous at all. Here's what I did:

01. Set parking brake and chock rear wheels.
02. Jack car very high up at center of crossmember.
03. Place 2 jack stands at frame near jack points.
04. Remove wheel, caliper, and sway bar with impact wrench.
05. Separate steering knuckle from outer tie rod.
06. Remove jack, place under control arm, jack up slightly.
07. Remove ball joint pinch bolt with impact wrench.
08. SLOWLY lower control arm, then remove spring.
09. Remove eccentric control arm bolts, then remove control arm.

Note in step 8, as long as you lower very slowly, there really is no need for a spring compressor. I rented the loaners from AutoZone to be safe, however the jaws were too big to fit between the coils so it turned out I couldn't use them anyway. Just for safety I ran a ratty old 20 amp extension cord through the spring as indicated by the yellow line in my previous picture above, but it never came into play and I don't see how it would since the control arm's geometry will not allow it to let go of the spring until the spring is almost fully extended. Once the ball joint pinch bolt is undone, the control arm just needs to drop somewhere between 45 and 90 degrees and you are home free.

At the end of the control arm travel, it appeared the arm was "springing" back up, making separation of the ball joint and subsequent removal of the spring a little precarious. Upon observation, it appears this was a function of the rubber bushings acting counter to the eccentric bolts; in the future I believe loosening the bolts enough to clear the eccentric will reduce or eliminate this springy feeling, allowing the control arm to drop all the way to 90 degrees more easily.

It does look like reinstalling the spring is going to be a royal pain, only because it is going to want to pop back out. But I'm sure I can get it to catch just a quarter inch of the control arm indentation, which is all that is needed to be able to raise the arm and compress the spring once again.

In summary, it is my opinion that a spring compressor is more of a convenience for this job. I could see where it could be essential for other jobs, such as when you wish to remove the spring without disturbing the ball joint and/or tie rod, etc. but for my purposes it was perfectly safe to remove the spring without one.

gmercoleza · #7 01-26-2007, 10:35 PM

Oh yeah, it took me about 1:45 to do this job, and 45 minutes of that was easily spent on separating the tie rod end. I actually damaged it in the process since it appears to have been overtorqued by me. I replaced the tie rod end when I first bought the car, and in my haste I recall guesstimating the torque - I admit, one of the few occasions I have ever done so. I had to use a torch, bent a tie rod puller, and couldn't even get it separated with a pickle fork. In the end, I used a large gear puller and it popped just before I thought the puller was going to break...

QuickSilver2 · #8 10-26-2007, 09:04 AM

Hi David:

I'll be calling you this morning, I hope you are still doing work.

I have a 99C230K and I need to insrtall Koni Sport Kit (I already have it).

Quote:

Originally Posted by david s poole

i agree it can be done but what are you trying to do? my shop is not that far from you and i have the benz spring compressor.call me,sat morns are usually free.

QuickSilver2 · #9 10-26-2007, 11:49 AM

Okay does anyone know where to rent/buy the correct compressor in Dallas area?

I am going to do this on a W202.

Thanks.