Rust at the bottom of the doors! - PeachParts Mercedes-Benz Forum

zeke · #1 10-16-2007, 10:38 AM

Car cancer

I hadn't seen these spots when I bought the car. I never even thought to look inside the door between the panel and the seal at the bottom - it's not one of those typical rust spots like the jack points, spring perch, etc.....

It is on the passenger front door and driver rear door. I am afraid it is happening on the other 2 doors but I can't see it yet

What should I do about this?

bustedbenz · #2 10-16-2007, 10:48 AM

Mine has it too, but not that bad yet. The little rail thing at the bottom of the doors collects little rust particles on the back doors... I'm just hoping they all hold together for a while. Don't know of much of a repair short of door replacement and then repainting the car so it all matches

Jordan G · #3 10-16-2007, 10:58 AM

I'm in need a similar repair - and I don't think there is an easy fix. I plan to just grind it out and slap some por15 on it to slow it down..... it's a nasty place to weld/rivet new metal in. No point in body filler IMHO, it's not really visible (yet).

chetwesley · #4 10-16-2007, 11:17 AM

I think that is a really common place for rust on 123s. My old 300TD had it there on an otherwise not very rusty car. My 126 doesn't seem to be affected by it though, despite having more overall rust. I think you could help the situation by routinely cleaning out salt from that area if you drive in a salty place, and by drying it out after it rains, as it seems moisture collects there.

zill · #5 10-16-2007, 07:44 PM

I have the same situation on my 240D. All 4 doors have some rot. The front passenger door is the worst and this summer bubbled the outside panel, yuk.
A new door shell from M/B is $800.00.
A used door shell is less than $200.00.
So this winter I am going to purchase a used shell. Have it painted transfer hardware, have the door aligned. Door by door I will replace all four. I guess it will run about $600 to $700.00/door. I will no doubt replace other corroded pieces in the door. That is included in my estimate.

Zill.

Hatterasguy · #6 10-16-2007, 07:46 PM

You can patch it with some POR.

Or fix it with rust free doors.

unkl300d · #7 10-16-2007, 08:01 PM

yeah, get on it and treat it n patch it. Since your color is orient red, doors may be hard to find.
I recently replaced both pasenger side doors on my 300D (IVORY) with help of a friend. (bad bondo work from many years ago. not rust.)
1 day each. about $155 for both doors n glass from some guy's donor car.

Cheaper than pro body work.

don't fret.

zeke · #8 10-17-2007, 10:24 AM

Thanks,
I will treat it with Por15 next month and see how long that holds!

JimFreeh · #9 10-17-2007, 10:44 AM

Rather surprised to see that amount of door rust on a Texas car.
Was the car originally from a wet or salty area of the state/country?

Jim

junqueyardjim · #10 10-17-2007, 11:12 AM

Short of replacing the doors, I think POR is the way to go. POR is an unbelievable product in the way it encapsulate rust and keeps it under control. It is "anhydrous" which means it takes water or water moisture to cure and it has extremely tough skin. If it were my job, I would remove the interior door panels and really get that POR to cover the lower inside part of the door. That is probably where the rust started. I just checked both of my cars. My 85 which has a lot of rust, the doors are rust free. My 84 which I consider totally rust free, is clean in that area also. So I suspect it is not road salt that is the damage maker in this case. I would think it is clogged door drains and/or faulty paint and metal finish in the doors that is the problem. So I would get that POR on now and stop further damage. I would paint that POR up at least 5 or 6 inches. Black POR is not resistant to UV, but I think you your safe using it there.

chetwesley · #11 10-17-2007, 11:18 AM

I keep hearing so much about this stuff... I have a couple of rusty spots that I am not about to try to restore, but which I would like to stop if I could. How much of this stuff do you need to just paint a few spots. I have no idea how it is applied. It is expensive, so that is why I ask how much you need

zeke · #12 10-17-2007, 11:40 AM

The PO was the OO (original owner), so I know that the history is accurate

This car was originally purchased in CA and lived the rest of its life in Houston.

So salt is not the issue. Houston is fairly close to the Gulf, though, so there is a good deal of rain and humidity there. Also, based on the amount of sand I found under the car and in the engine compartment, I think he may have taken this car to the beach from time to time. Clogged door drains may be the culprit - where are those located?

I found this starter kit:
http://www.por15.com/prodinfo.asp?grp=SSK&dept=1

It has everything you need (degreaser, prep, Por15) and is supposed to be enough to treat 12 square feet which should be enough for those 2 doors, even with a pretty thick coating.

I will take off the panel and really try to give it a good coating. I am most worried about the metal degrading to a point where the door seals no longer have a seat.

junqueyardjim · #13 10-17-2007, 12:03 PM

It is not expensive and is quite easy to use. Remember that you cannot use the black in an area that gets sun. If you do use it in the sunlight areas, it has to be well covered to keep UV rays from getting to it. You can buy the 4 can "starter kit" for $29.00 or so. Includes 4 cans of 4 oz. each, a couple brushes, 2 types of metal prep and very important rubber gloves and I think a sheet of fiber glass cloth.. The stuff does not irratate skin, just is nothing to take it off, even wet. Takes a good week to wear off. When you open a can, pour about what you need into a small throw away container that you can paint from - baby food jar, screw on lid cover, very cheap plastic cup or dish. Reseal can asap! Moisture in the air immediately starts to cure this stuff. When not using it, I keep it well closed in the back of our extra refrigerator. Shelf life in the fiidge is a couple of years. Shelf life in the heat of the garage is not good. Use like paint. Remove any easy to remove rust scale. Try to remove anything that might flake off. Then go at it and paint it up. Just don't paint anything you don't want painted. Works good with fiber glass cloth. Paint the area around the hole and while it is wet lay in a piece of fg fabric cut to size. Lay it over the hole and keep it as tight as possible. When it is dry, (does not take long when hot and humid) paint the cloth. Makes a very tough repair - extremely tough, but not as tough as steel. But it will really wear well. Just do a search for POR and you will come up with endless buisnesses that sell it. I have bought it a couple of time from Amazon.com. I think the silver is UV resistant, but don't know if it came in the starter kit - yes I am sure it does. Just remember to check to be sure it is UV resistant if you are using it on the topside, that is very important. It just has no strength in sunlight. It really is a wonderful product. I keep about a dozen of those cheap little Wally World paint brushes handy, because once you use one, if you let the brush sit for 10 or 15 minutes, it gets so hard you cant use it again. When you finish painting, throw your paint container with left over paint away. Do not pour it in with good paint because the moisture it has picked up in the time you were using it will ruin the rest of the paint in the container, if you pour it back.

junqueyardjim · #14 10-17-2007, 06:57 PM

There are many threads on using POR in the rust repair section, under the heading "Restoration". Many different users report on it.

unkl300d · #15 10-17-2007, 08:46 PM

When you remove the interior door panels to reveal the door cavity, check your window 'frame'. The lower metal strip that is glued to the window pane bottom and attaches to the regulator arm.
If that is rusted, it may indicate that your window rubber moldings are allowing water inside the door cavity when it rains.
Ergo it also accumulates at the bottom.

If bad, try regluing to glass because at some point the glass may slip out of it. (happened to me. I replaced glass with junque yard parts), also installed new moldings.

If you don't have small drain hole at the bottom, just drill out one or two and treat the edges with the POR so it does not rust.

Good luck.