1994 E420 Project

[vatc5637]

So after mulling it over for a week or so, I’ve decided to try to keep my ’94 E420 with 190,000 miles on the road and save it from the wrecker.

I’ve owned this car since 1999, when I bought it from my brother–in-law with 46,000 miles on it. Until recently, it was well maintained and relatively trouble-free. In 2006, the car went from being my daily driver to the first (learning to drive) car of my children (3 boys, 1 girl). It served that assignment with distinction, keeping all 4 safe from inexperience, deer, parking posts, inattentive drivers, etc. Unfortunately, the car itself went from relatively pristine to, well, a beater. Last week, it officially came back to me.

While both the exterior and interior are a mess, my primary concern is certain mechanicals. It’s very loose in the front end, the transmission is headed south, there are oil, transmission, and power steering fluid leaks everywhere and the CEL is on. I had my trusted indy spend an hour going thru it to confirm my own diagnosis. We agree that immediate issues (in order of urgency) are:

1. Lower control arms (balls joints have deteriorated badly)
2. Power steering pump leaking “like a sieve”
3. Steering box leaking
4. Center link needs to be replaced
5. Except for shocks, most of front suspension is original
6. Transmission leaks (side seals?)

As reasonable as my indy is, having him repair the car is out of the question. So, as a challenge to myself, I’ve decided to try and repair this car myself. While I am willing to spend money, part of the challenge will be to be smart about it. I’m going to try to use “used” OE parts. I will consider some less than “OE” quality new parts where feasible, but I absolutely will not use sub-standard parts (no URO!)

Current plan is to:

• Replace lca’s
• Pull p/s pump and rebuild
• Pull steering box and rebuild
• Replace p/s hoses (probably original)
• Examine and possibly replaced front suspension/steering components

Any and all comments are welcome and solicited. This should be an interesting experience, stay tuned.

 

[gsxr]

1) Replace the drag link and both tie rod assemblies with new Lemforder. Don't skimp on safety items. Check the idler arm closely, spec is 0.5mm play max IIRC. The steering should be tight.

2) If your ball joints are tight, you can rebuild the LCA's with new Lemforder bushings and new BJ dust boots, to save a bundle compared to new OE LCA's. You'll need a large bench vise and probably an aftermarket bushing tool, unless you're really creative. Be super careful with bushing orientation, photos are on my website, don't get this screwed up.

3) P/S pump is straightforward, multiple threads on several forums with good photos. You can re-seal the steering box without removing it from the car and trust me, you don't want to pull the box if you can avoid it. If re-sealing everything else, also make sure to change the two hoses at the frame rail (S-hose, and short straight one behind the heat shield). See my steering box re-seal thread on this forum.

4) After the steering linkage stuff, check EVERYTHING else that may affect alignment (struts, strut mounts, rear links, especially rear carrier joints). Dealer alignments have increased to $150-$200 and you only want to pay for one alignment.

Hopefully should be under ~$500 in parts if you do all the work... assuming you don't have any surprises along the way. New LCA's will be $800+ if you go that route, or if it's required due to excess BJ play.

 

[Glen]

Sounds like a great project. We'll be here to help as you progress through it. Dive right in, you can do it!

 

[gerryvz]

Good luck, Terry. Look forward to seeing the results in May ?!?

I have found that with my big projects, it's helpful to post "nightly" updates to the forum (or as often as I'm out in the shop) as it both helps me keep people informed, keep photographic evidence of how things go together, and also keeps me motivated to move the job along, as it would be extremely embarrassing if I gave up on a project in front of the whole forum !! I also keep a written notebook of the major steps I do in disassembling and re-assembling things (in addition to photos) so that I know the order in which I did things. Again, this is helpful, and also serves as a place to write down parts that need replacing "on the fly" out in the shop so I can look up their numbers and costs when I come back inside.

Love it when people embark on big jobs and keep folks informed! Again, good luck !

 

[vatc5637]

Thanks everyone for the words of encouragement.

I've started to assemble the parts for this project, starting with the front lca's and steering bits. My "new" used lca's arrived today and upon inspection, the ball joint boots appear intact. The ball joints rotate and there doesn't appear to be any play in them. My current plan is to re-pack them in grease and install new rubber boots. I will order the 2 lemforder bushing repair kits (p/n 124 330 06 75). BTW, this was the 500E p/n I used last year, I assume that the .034 uses the same number, please correct me if I'm wrong. (as an aside, I think that I will have to sign up for the EPC now so as not to drive everyone else crazy looking up part no's for me).



I remembered that when I did my front suspension refresh for the 500E last year, I saved some of the old pieces. The tie rods appear to be in good condition. All the boots are intact, with no rips or tears, still greased. According to the records the PO gave me, they were replaced in '08, about 35,000 miles ago.



Same appears to be true of the center link.



RE: bushing tool, anyone looking to sell one? If not, any suggestions on what brand and where to get one?

Thanks for your interest and comments.

 

[gsxr]

The factory LCA bushing tool went stupid in price last year (~$1k, IIRC). There are some aftermarket ones on eBay for ~$150. I think you can do the job without it, assuming you have either a large vise or a press, but the tool would make it easier.

Last I checked, the boots for the tie rods / drag link (129-330-00-85) were NLA. Be nice to them during installation.

 

[samiam44]

Most of the time the steering box is the lower seal- you can just replace it, and the hose sections. Lower seal and o-rings are fairly inexpensive.

Side seals on the transmission. There are lots of external covers. B1 is a bitch to do in the car, B2 is easier and more common leak point, kick down solenoid.

Too bad you cannot round up a front bumper used- keep your eyes peeled at the junkyard.

Michael

 

[sheward]

I think you can do the job without it, assuming you have either a large vise or a press, but the tool would make it easier.

One could probably buy a press at Harbor Freight for less than $150.00

drew

 

[vatc5637]

Too bad you cannot round up a front bumper used- keep your eyes peeled at the junkyard.

Michael

Will do, just wasn't a priority at this time. Hopefully, one of the local yards will have one at some point in time.

 

[gerryvz]

There's a HOW-TO on the lower steering box re-seal at this location.

It's not all that difficult of a job.

Terry, I understand you are trying to go with used factory parts and stuff you have on hand. I would recommend that you buy new tie rods and drag link -- they aren't all that expensive new, if you get Lemforder units from AutohauZ.

It's also a good idea that you replace the idler arm bushing. That is only available from MB and is not particularly cheap for what it is, but it can and does make a difference since you are refreshing other items on the front end.

Cheers,
Gerry

 

[vatc5637]

Been gathering parts (and courage) for these jobs. Now just waiting on their delivery. Also studying the FSM and various threads here to put together a plan of attack. Some questions I have:

1. I was going to begin with the removing the driver's side lca, then once it was removed, switch over to the p/s pump removal. Once the p/s pump was out, I was thinking that re-sealing the steering box and replacing the p/s hoses was my next step. Thoughts? Also, I'm pretty sure all of these parts are coated with crud and "seized" together to some degree. Any tips from the pros on how best to break this stuff loose would be appreciated. I do have access to some air tools if need be.

2. Prior to removing the lca, it appears that I will need to remove the front spring, which in turn requires a spring compressor. Is there any specific style or type of compressor that I should focus on getting? or will any legit spring compressor work? Can these be "rented" or must they be purchased?

3. I recall that there was a thread somewhere on the appropriate grease for the ball joints and new MB OE bushings that will go into the lca's , but can't seem to locate it. I'd appreciate it if someone would either tell me the appropriate grease or id the thread.

Thanks very much.

 

[gsxr]

1) Removing the driver LCA may not help much with PS pump R&R. Removing the vertical plastic/rubber shield that goes around the sway bar will help visibility and access. The hoses and box are all kinda separate from the pump itself, so the main advantage to lumping the jobs together is you only drain the system once. Get some OE p/s fluid from the dealer to re-fill, don't forget a new filter while you're in there.

2) You'll need a Mercedes Klann-style spring compressor. The Chinese clones allegedly work fairly well and are under $200 delivered. SG-Motorsports (forum member in Seattle) sells one, click here. You can always re-sell it when you're done to recoup some of the investment, kind of a self-rental without the hassles of shipping or limited rental time.

3) Not sure what is the recommended grease to add to existing grease for BJ's, maybe Clark or Klink can chime in. For bushing installation MB has special sliding fluid, but any rubber-safe lubricant will be fine. The lube is not critical to the installation job as the bushings are retained by metal-to-metal contact. Don't forget to clamp/peen the center tube after installing the bushings, a couple of short wheel lug bolts in a large bench vise work nicely.

 

[vatc5637]

. . . Don't forget to clamp/peen the center tube after installing the bushings, a couple of short wheel lug bolts in a large bench vise work nicely.

I get why I need to do this but I'm not sure I understand how. Would you please elaborate? TIA

 

[gsxr]

I get why I need to do this but I'm not sure I understand how. Would you please elaborate? TIA

It's mostly a convenience item to hold the bushings closer, to make installation easier. The eccentric bolt at 150Nm is going to exert far more clamping force than the little sleeve flares.

What I do is insert a stubby OE lug bolt (with ball seat) in each end, and clamp it together in a bench vise. This compresses + flares at the same time. Not as slick as the factory tool, but works well enough.

 

[Klink]

It's mostly a convenience item to hold the bushings closer, to make installation easier. The eccentric bolt at 150Nm is going to exert far more clamping force than the little sleeve flares.

What I do is insert a stubby OE lug bolt (with ball seat) in each end, and clamp it together in a bench vise. This compresses + flares at the same time. Not as slick as the factory tool, but works well enough.

Once again, Gixxer hits a home run with the bases loaded...

 

[vatc5637]

What I do is insert a stubby OE lug bolt (with ball seat) in each end, and clamp it together in a bench vise. . . .

Ahhhhh . . . now I see sayeth the blind man.