Front Suspension Rebuild Help For Green Horn - PeachParts Mercedes-Benz Forum

Father Of Giants · #1 02-05-2018, 11:05 AM

I've never done any kind of suspension work in my life, so I know nearly nothing about it's main and supporting components. You can NOT offend me by giving me "obvious/too much info"

So, my car failed inspection due to worn suspension parts, I knew this was going to happen so it wasn't a shocker.

My goal is to replace as many old parts as I can.

My list consists of the following for the front.

Idler Arm repair Kit
Left and right tie rod assembly
Steering damper - (I know you don't NEED it but I want to replace regardless)
Center Link
Guide rod mount
Stabilizer Bar
Control arm repair kit 1263300075
Sachs shocks x2
Control Arm Ball Joints (already have at hand)

Did I miss anything by chance?

What kind of special tools do I need in order to replace the following components above, I don't want to leave anything on the table.

Also would it be best to do everything at once (one side at a time of course)? And in what order should I work in the suspension from the out side in?
Ex [OUT SIDE] Tie rods to ---- ???? [INSIDE]
[OUT SIDE] Control arm to --- ???? [INSIDE] If that makes sense.

Thanks!

HuskyMan · #2 02-05-2018, 11:17 AM

Funny, I'm about to start the same project. You are going to need a spring compressor, there are some chinese made ones available on ebay and amazon. Or, you could try and rent one from several members on this web site, You may be able to rent a higher quality compressor from a forum member.

I'm planning on acquiring a full facial coverage motorcycle helmet just in case a spring goes postal. I'm also considering chaining or tieing a heavy duty rope from the spring to the car chassis.

there are too many stories about mercedes srpings causing serious injury, so any measures you can take to insure your personal safety are worth it.

You will also need to purchase two (2) eccentric pin/bolt kits from either this web site or ebay. When you get into it, you may not need them, but then again, you might so best to have them on the ready.

I figure while I'm in the middle of it, I'm going to check out the condition of the brakes rotors and pads and if they need replaced, go ahead and replace them.

This is a fairly extensive job, some people choose to take their mercedes to a front end suspension shop instead of DIY. I know if I had the coin, I'd take the car to a professional shop, sit back and drink a starbucks while they did the work.

Father Of Giants · #3 02-05-2018, 11:28 AM

Quote:

Originally Posted by HuskyMan

Funny, I'm about to start the same project. You are going to need a spring compressor, there are some chinese made ones available on ebay and amazon. Or, you could try and rent one from several members on this web site, You may be able to rent a higher quality compressor from a forum member.

I'm planning on acquiring a full facial coverage motorcycle helmet just in case a spring goes postal. I'm also considering chaining or tieing a heavy duty rope from the spring to the car chassis.

there are too many stories about mercedes srpings causing serious injury, so any measures you can take to insure your personal safety are worth it.

You will also need to purchase two (2) eccentric pin/bolt kits from either this web site or ebay. When you get into it, you may not need them, but then again, you might so best to have them on the ready.

I figure while I'm in the middle of it, I'm going to check out the condition of the brakes rotors and pads and if they need replaced, go ahead and replace them.

This is a fairly extensive job, some people choose to take their mercedes to a front end suspension shop instead of DIY. I know if I had the coin, I'd take the car to a professional shop, sit back and drink a starbucks while they did the work.

Same here, wish I could give it to the shop and POOF! It's ready, but I'm far from rich or well off.
I heard that by looseing lowering the control arm you relieve a lot of tension from the spring, allowing you to use the cheap spring compressor with far less risk. They also said doing may destroy the old bushing so it's wise to have new ones in hand.

I'll add the eccentric bolts and pins.

I'd be delighted to borrow tools if possible, would make life much easier.

jake12tech · #4 02-05-2018, 01:12 PM

What's worn out? Replace only what's broken and failed on the inspection. That's where people go wrong fixing things that aren't broken.

Father Of Giants · #5 02-05-2018, 04:39 PM

Quote:

Originally Posted by jake12tech

What's worn out? Replace only what's broken and failed on the inspection. That's where people go wrong fixing things that aren't broken.

The only thing I DON'T know if it's worn is the guide rod mount, those usually are worn out when the control arm goes out too. From what I've seen from the history of this car, the previous owner didn't do ANYTHING to the car. I've replaced tons of stuff because of neglect. When I got the car the tie rods where new! New Meyle junk that failed in less than 10k miles.

As I know of.

Tie rods
Front Control arms
Idler arm
Shocks
Steering dampener
Center link are all shot.

I'll check other components when I get time

Mxfrank · #6 02-05-2018, 04:57 PM

Wait! I think I hear some tappet noise. Have you changed your oil recently?

Hit Man X · #7 02-05-2018, 05:04 PM

At 300k, the car needs it all if original.

Add coil springs to your list as they do sag with age. BTDT. Same with new shims. Caster rod/guide rod mounts fail pretty often on these as they take the load and debris from the road can puncture the boot, ball joints last a long while. The clover looking deal on the back of the guide rod bush will induce some noise before the bushing fails. You can always reboot a BJ if you catch it early enough, I have after a front end build. Remove that back cover and whack the caster rod on the ground and the old assembly will pop right out, seriously. Clean that scale in there until shiny. Toss them in the freezer and prep your hydraulic press, they go in easy with Astroglide or the like. Consider replacing the two bushings per bracket too.

LCA bushings are a nightmare to press in square. I suggest buying an additional kit just in case and/or finding a shop that can do them. I lack the skill or tools to press all three pieces in correctly. I bought the BJ tool and it has paid for itself many times over. Many people rig up all sorts of things for those, once you use the real tool for the BJs you will never try another way. A 5lb sledge and a 27mm? socket works perfect to pound the old ones out. Spray with Kroil or the like and let sit overnight.

I have done front ends on five W126 now, I am faster each time but certainly there are more tricks I have yet to discover. Just mark it all and pull it all out at once. A scribe is your pal here on the LCA eccentrics to get you in the ball park. Use a tape measure to make the caster rods as close as you can.

Agreed on brake rotors, if questionable... do them. Repack the bearings is a given. Mind their specific end play!

You will be amazed how tight and quiet a fresh front end is on these cars. Hope you can find a shop smart enough to align these, bad tires will induce pull. I think we add about 1* additional caster on passenger side due to road curvature.

Good luck!

ROLLGUY · #8 02-05-2018, 05:30 PM

I have a rebuild thread here somewhere (a few years old) if you care to search. The whole job is not that difficult. Removing the springs is definitely the most challenging part of the job, but not as bad as it could be without the proper spring compressor. The first one I did with with the cheap threaded rod type. It was sussessful, but very scary to say the least. I had better luck starting with the weight on the spring, as the tool seemed not long enough to work with the spring extended. I could not get the spring compressed enough to get it in its place, and still have enough threads started in the compressor. You might have a different experience than I, so try it first with no load on the spring (suspension fully extended, and shock disconnected). Although I doubt the spring will spit itself out, I would still have your jack under the LCA for safety.
For the LCA bushings, you can use threaded Rod and washers/nuts if you don't have a press (a big vise works good too). I used the HF "C" press to install the lower ball joints, and it worked great. Yes a press and the purpose made tool is better, but I did not have the time to wait for delivery of the tool (already had the front end apart), nor the money for the tool.

MongooseGA · #9 02-05-2018, 05:53 PM

I just completed this, and I'm also a fellow Hampton Roads-er (though in ATL now).

Feel free to shoot me a DM, it sounds like you have about the same experience level I did when I started. I'd be happy to chat with you in real time if it's helpful.

Father Of Giants · #10 02-05-2018, 06:22 PM

Quote:

Originally Posted by MongooseGA

I just completed this, and I'm also a fellow Hampton Roads-er (though in ATL now).

Feel free to shoot me a DM, it sounds like you have about the same experience level I did when I started. I'd be happy to chat with you in real time if it's helpful.

Thank you, I 'll definitely reach out to you.

Junkman · #11 02-05-2018, 09:19 PM

Quote:

Originally Posted by jake12tech

What's worn out? Replace only what's broken and failed on the inspection. That's where people go wrong fixing things that aren't broken.

I call bull. Springs out means it's getting everything that spring removal is required or even makes R&R easier. He wouldn't be refurbishing the front end if it were in good shape. POs have gone way past where parts should have been changed on these cars.

The inexpensive spring compressors from FleaBay work. I didn't like the amount of tension but it held. I market the compressor so that I could know the plate was engaged properly with the shaft. Take your time and be sure that the plates properly engage with the spring. You don't want the thing to fly across the room or into your head.

Grease the threaded part of the compressor.

leathermang · #12 02-06-2018, 11:20 AM

Quote:

Originally Posted by Junkman

I call bull. Springs out means it's getting everything that spring removal is required or even makes R&R easier. He wouldn't be refurbishing the front end if it were in good shape. POs have gone way past where parts should have been changed on these cars.

The inexpensive spring compressors from FleaBay work. I didn't like the amount of tension but it held. I market the compressor so that I could know the plate was engaged properly with the shaft. Take your time and be sure that the plates properly engage with the spring. You don't want the thing to fly across the room or into your head.

Grease the threaded part of the compressor.

I agree....
Have someone close by with a phone to call 911 just in case.... I actually recommend that on a job like this OR brake work one either watch someone else do it the first time.. or at least have them supervise you closely... steering, suspension and brakes are not things to take chances on not being SAFE... or being Done in a SAFE manner....

Maxbumpo · #13 02-06-2018, 02:13 PM

Tool: Get a Harbor Freight Saw-z-all and good blades from another store so you can cut apart whatever is too rusty to waste time on. I'm not familiar with inner bushings on the lower control arm on a 126, I've done that job on 123 and 124, and it is a real pain. Old bushings need to be cut apart and forced out. If you find rust on the inner surface of the LCA, you need to either clean up the rust or buy a new LCA if the rust is too deep.

Another Tool: Harbor Freight big massive C-clamp for front end bushings. I use this to install the new bushings (I coat them with castor oil as lube) and the inner sleeve, the opening on the C-clamp opposite the threaded rod "pusher" gives access to the part of the sleeve that needs to be peened to hold the assembly in place. Ball peen hammer (third tool), held in place on the sleeve, strike the other side of the hammer with a hammer or mallet or whatever.

I've also made good use of a massive piece of all-thread rod with big washers and sockets to help remove old bushings. A blue wrench (torch) may also be useful.

leathermang · #14 02-06-2018, 04:15 PM

Quote:

Originally Posted by Maxbumpo

Tool: Get a Harbor Freight Saw-z-all and good blades from another store.....

'' From another store'''

I had one of these grit blades last 20 years with me using it regularly... let the grit do the work... amazing... this is not the only brand of grit sawszall blades.. just an example ...

https://www.milwaukeetool.com/accessories/cutting/48-00-1430