Rust HELP!!!!!!!!!! - PeachParts Mercedes-Benz Forum

deerefanatic · #1 01-02-2006, 10:58 AM

Hi guys, I made a scary discover new years eve when i was changing my oil. I got in the trunk to get my oil filter and the box was soaked! I began ripping out carpet linings and found the source.

Only the "side pockets" have water in them. The spare tire well is dry, thankfully.

The side pocket on the drivers side has a large 4-6 inch hole right above the exhaust pipe, and another large one under and behind the power antenna motor. On the passenger's side, the weld seams are already rusted out.

I am planning to cut out all the side well pockets and get it clear back to clean metal. Then reconstruct the side wells with long-strand fiberglass.

Any tips? I know my trusted body guy will sell me good quality products for a fair price. I also planned to slope the new side wells back toward the rear of car so that water will drain back to a water drain.

R Leo · #2 01-02-2006, 11:02 AM

The pinch weld under the bottom of your rear window is probably rusted-out too. My '84 is missing about 6" of the pinch weld seam which allows rainwater to fill the trunk pockets and right rear floorboard in any sort of a rain.

TheDon · #3 01-02-2006, 11:21 AM

i found rust on my 300D-T today.. i knew about it before but it spread a little bit.. its behind the left rear wheel.. im thinkn about sanding it down to bare metal around it and getting rid of all the rust the putting some rust stop stuff on it and finding some paint to match up.. id ride around with the red spot of primer as long as the rust is gone

deerefanatic · #4 01-02-2006, 12:07 PM

Quote:

Originally Posted by R Leo

The pinch weld under the bottom of your rear window is probably rusted-out too. My '84 is missing about 6" of the pinch weld seam which allows rainwater to fill the trunk pockets and right rear floorboard in
any sort of a rain.

Wouldn't that also allow water in on the metal of the rear shelf? I had the parcel shelf off installing new 6.5 speakers and found no traces whatever of water having ever been present there. I also know it isn't the sunroof drains.

whunter · #5 01-02-2006, 12:10 PM

Quote:

Originally Posted by deerefanatic

The side pocket on the drivers side has a large 4-6 inch hole right above the exhaust pipe, and another large one under and behind the power antenna motor. On the passenger's side, the weld seams are already rusted out.

I am planning to cut out all the side well pockets and get it clear back to clean metal. Then reconstruct the side wells with long-strand fiberglass.

The area you refer to is part of the quarter panel support and impact crumple zone = safety structure = it is structural damage, and must be welded.

Rust stoppers.
Rust stoppers.

Welding the wrong metals can kill you
http://www.peachparts.com/shopforum/bodywork-repair-paint-tools-tips-tricks/139957-welding-wrong-metals-can-kill-you.html#post1041594

R Leo · #6 01-02-2006, 12:25 PM

Quote:

Originally Posted by deerefanatic

Wouldn't that also allow water in on the metal of the rear shelf? I had the parcel shelf off installing new 6.5 speakers and found no traces whatever of water having ever been present there. I also know it isn't the sunroof drains.

I've never seen evidence of water on the rear shelf metal. I cannot tell for certain but, it think the water from the missing pinch weld runs underneath the window, behind the shelf, and outboard to a point where it drips off, landing on the aft side of the wheel arch. From there, some runs into the trunk pockets and some runs forward, under the seat to the footwell.

Since it hasn't rained here since late July, I don't worry about it all that much.

boneheaddoctor · #7 01-02-2006, 12:43 PM

Quote:

Originally Posted by TheDon

i found rust on my 300D-T today.. i knew about it before but it spread a little bit.. its behind the left rear wheel.. im thinkn about sanding it down to bare metal around it and getting rid of all the rust the putting some rust stop stuff on it and finding some paint to match up.. id ride around with the red spot of primer as long as the rust is gone

never run around with just primer....most primers (catalyzed primer being the exception) are porous and moisture will still get to the metal under it....making it rust again...so even if its a butt ugly color get some topcoat on primer ASAP whenever you do any body work.

Matt L · #8 01-02-2006, 02:38 PM

Quote:

Originally Posted by boneheaddoctor

....most primers (catalyzed primer being the exception) are porous and moisture will still get to the metal under it....

Better still, use a nice urethane primer and a topcoat. I don't see any need to use a noncatalyzed primer.

bgkast · #9 01-02-2006, 03:44 PM

I found some rust yesterday too. there is a bunch of surface rust under my trunk seal and in the corners of my drivers and passenger doors. Time to order some POR-15.

R Leo- How do you know that 6" of your pinch weld is missing? Did you pull your window out or can you see it with the window in place? I'm hoping my trunk leak problem is the trunk seal and not the rear window...

pwogaman · #10 01-02-2006, 11:06 PM

Quote:

Originally Posted by deerefanatic

Only the "side pockets" have water in them. The spare tire well is dry, thankfully.

The side pocket on the drivers side has a large 4-6 inch hole right above the exhaust pipe, and another large one under and behind the power antenna motor. On the passenger's side, the weld seams are already rusted out.

I am planning to cut out all the side well pockets and get it clear back to clean metal. Then reconstruct the side wells with long-strand fiberglass.

Any tips? I know my trusted body guy will sell me good quality products for a fair price. I also planned to slope the new side wells back toward the rear of car so that water will drain back to a water drain.

Here are my tips: Rust Never Sleeps

Sounds like you have exactly the same problem I had.

whunter · #11 01-02-2006, 11:47 PM

Quote:

Originally Posted by pwogaman

Here are my tips: Rust Never Sleeps

Sounds like you have exactly the same problem I had.

Yes, that is a very nice repair!!!

Pete Burton · #12 01-03-2006, 12:05 AM

I had a water problem there too. Never any water on the shelf. Bad rear window seal. Once I replaced that, it's been dry as a bone.

bgkast · #13 01-03-2006, 08:15 PM

what did it cost to have the seal replaced?

deerefanatic · #14 01-06-2006, 09:14 PM

Here are some pics of the damage. (Will try to get some pics of repair soon....)

First, the passenger side leak temporary fix:

Rusted out fender support seams:

Rusted out pocket floor:

Taillight leaks:

So, that's the damage.

Whiskeydan · #15 01-06-2006, 10:20 PM

Has anyone ever tried muriatic acid to remove all the rust, neutralize, treat then repair?
I've clean all rust off of metal parts using acid. It must be rinsed well then treated.
Once I found an old wrench while digging in the yard. For grins I put it in an acid bath, forgot it and came back a day later to maybe 10% of a wrench.