I have a 1989 300TE that is in great shape and very rust free but when I was jacking up the car last week to do some work I saw bubbles around the jack points..... so I pulled the plugs out and it is pretty bad.

I am hoping to get some good information instead of toss the wagon and find a new one.

I have seen it mentioned that people have repaired the rockers and left out the jack holes. Has anyone seen or done this?

I am wondering how the inner rockers and jack holes are put together. If you look at this thread on post 14 there are some pictures but it is hard to tell what is going on in there (it is on benzworld, I hope posting that here is ok) http://www.benzworld.org/forums/w123-e-ce-d-cd-td/1350464-my-aching-holes-2.html

I am thinking at this point I have two options (without digging too much into it) for repair....I can get the full rocker panels, secure the car, and replace the whole thing....Or I can get the jack points from a donor car (about 6 to 8 inches before and after), carefully start grinding out the rust hoping that I do not have to cut out the whole piece, and use the donor pieces to put the jack points back together.

Any pictures, ideas, suggestions would be great.

As a first step, I would use a good rotary wire brush - a twisted wire one, mounted on an electric drill works OK. You want to remove rust, not solid metal - and grinder will take both off..
See where this takes you....

thanks for the suggestion andydiesel, I definitely want to go about this like an exploratory procedure and not having to dig in deeper than I have too. I am thinking of cutting a small piece around the the jack point so I can get in with ospho or some phosphoric acid rust killer, paint with hammerite (spelling?) or something of that nature), and then spray waxoyl. weld the patch in, and then spray waxoyl all over the inside of the rockers.

It will be a few days until I can get the wire wheel and the time to do it but I will be posting pictures of before & after wire brushing.

The attached gives a limited view of what's inside the sill near jack point on a 126. Basically the jack tube is straddled by two gussets. There are round plugs in the wheelwells - where the half circle cutout is - (may be hidden behind underoating) - removing them may give you an idea how far the rot has reached.

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I have the same problem. One side worse then the other of course and it seems to be the front drivers side the worst.. Whats the best way to go about fixing this kind of thing? will post pictures later.

Finally got time to upload a few pictures of my jacking points after I poked at them a bit, the rear jack points seem to be solid, the front drivers side is pretty rough but I am hoping that it won't need to much work, and the front passenger side will definitely need some work.

all4MB, I have been scouring the internet in search of people who have done this repair....Most of what I find are threads that people started or posted or blogs they linked to that use to have detailed information or pictures but the pictures are no longer available and the blogs are no longer there.

When you are searching you have to use any word that could have possibly been used (The link I posted in my first post got a hit because I used "Jack Holes) and also try them again with W124 or W123, there are a lot of W123 users that have gone through this. There is also a bunch of info on UK based sites so when you run your searches you have to use terms that the UK boys would use, Like "Sill" instead of "rocker".

If I can find the ones that gave any info I will post them up here.

I would like to repair the jack points, coat them, and cover them up with the new patch piece going on the rocker.


And now it's time for pictures, I will get some new ones posted as soon as I get some time to grind and possibly hit it with the sand blaster.



Passenger Side Rear


Drivers Side Rear


Drivers Side Front


Passenger Side Front

Yours are alot worse then mine this is the worst

others seem to be OK.

You really need to get a wire wheel attachment for a drill and go to town stripping to bare metal and removing all the rust to see how extensive the damage is. Three of them don't look too bad , but the passenger side front will be a big hole once you start probing. Likely the internal structural support will be okay. Again, you will see more once you open it up.

POR-15 or other rust coating will be needed.

The question is: How long do you expect to keep the car? If more than a few years I would do it right an weld in new sections around the jack hole.

If shorter than that and is structurally sound , a cosmetic fix will do.

I found a section from a donor junkyard that I cut out and patched perfectly in place around the hole. It was structurally perfect under it.....thankfully!

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1987 300TD 147,000 miles- Palomino leather interior, 1995 facelift and body cladding, E350 wheels, Rebuilt suspension and sport springs, rebuilt turbo, New Monarch injection pump and injectors....and the list goes on and on...

May I ask how much you paid for the piece from the junkyard and also how you were able to cut it out in a remote area?

I will be stopping by a junkyard to check out a couple MB's that my neighbor said he saw there, while looking for parts for his own MB.

I will also be getting the wire wheel attachment to clean things up a bit, If I am lucky I will get to it today or tomorrow.

I also plan to be keeping this car for a while, It is in really nice shape and other than this and a few other little or inconvenience type issues I think she is up for another 130,000 miles.

I cut out a much larger section with a 18V sawzall and a sharp short metal or demolition blade. Around the jack hole I used a cordless drill and a multi-cone step drill bit. This allowed me to grind away around the jack hole and set it free. That took some time! An extra battery would be good. I had to go home charge up again and come back.

Since I had bought other parts there, he let me have it for free.

The bad part about rust is that it's a lot more extensive than it appears. If you have rust in those areas, you likely have rust in many more hidden areas. (under window trim, trunk, behind weatherstripping, around critical suspension supports, fuel lines, etc. Not trying to freak you out, but it's true.

Keep us up to date and good luck!

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1987 300TD 147,000 miles- Palomino leather interior, 1995 facelift and body cladding, E350 wheels, Rebuilt suspension and sport springs, rebuilt turbo, New Monarch injection pump and injectors....and the list goes on and on...

Thank you for the info on how you removed it. I do have a cordless drill, two or three stepper bits, and a cordless sawzall....I actually thought the cordless sawzall was useless but I may change my mind after this. I am also wondering if I could get an inverter and use my old fashion plug in tools so I do not have to worry about recharging.

I know all to well about "if you see rust there is even more you don't see) and there is a very small spot on top of the core support and the typical surface stuff you see on the suspension but other than that it is very clean, maybe I am just missing and need to crawl under and poke around with my halogen lights blazing. I will hopefully be taking the glass out, removing the trim, and prepping it for paint this year....maybe early next year, so we will if there is any hiding.

I will be updating this as I progress and will be posting up the links I found as well.

Made some progress today cleaning up the metal to get a better look at how big of a piece I need to cut out at the junkyard.
I will probably make it to the junkyard Monday or Tuesday and I already have my sandblaster out so I will be using that to clean up a little bit...hopefully if everything go's well it will be done by next weekend.

Front Drivers Side


Front Passenger Side


Rear Passenger Side


Rear Drivers Side

Two of the three are good at least! You may be able to get by with some patch welding rather than getting a while new "used" rocker section.

With some POR-15 and their epoxy putty you can smooth out the finish and be back in business. Top coat with some rubberized undercoating to match the rest.

Let us know how it's going

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1987 300TD 147,000 miles- Palomino leather interior, 1995 facelift and body cladding, E350 wheels, Rebuilt suspension and sport springs, rebuilt turbo, New Monarch injection pump and injectors....and the list goes on and on...