300SE 1990, 217,000 miles

Rust spots around bumpers, in corners, starting in engine compartment and light under body, Would appreciate a good advise.

Attached Thumbnails

     

For the engine compartment as much as you can wire brush/light grinding weld repair anything structural and coat with POR-15. I was lucky enough on the fenders to find an exact donor car to replace both fenders after getting bumped by a van a few years ago. For the under body same as engine compartment. As long as it not exposed to direct sunlight POR-15 is great on any rusting areas. Just clean as well as possible. I also suggest you check the clean outs in your rear fenderwells as they rust out at the same time as those other areas. I cleaned mine and used a fiberglass kit with POR-15 to stop the cancer there. Its not the best but a year has gone buy and evrything seems to be stopped that has been treated. Damn salted roads in IL. Now in Wa no more salt.

No body experts on this site today???

There is a forum JUST for body work..........

__________________
Click here to see the items I have up for auction at EBay

Click here to see a photo album of my '62 Sprite Project Moneypit (Now Sold)

Fixing rust on the Class A finish panels is a waste of time unless the car is retired from salt duty. I'm speaking from 35 years experience of working on rusty cars and owning them for a long time. Any fix will rust through in short order. Once the factory surface treatments are breached, there is little you can do to restore the surface to it's original corrosion-resistant condition. Your time is better spent on prevention.

The corrosion inside the car can be removed (sandblasting, wirewheeling) and rustproofed to prevent further damage by the environment.

That car is in mint condition compared to my w126.

__________________
08 R320 CDI current

Past
95 E420
87 300D Turbo 5spd
90 300TE
83 300SD
85 300TD
92 400E
85 190D

I couldn't agree more. IMHO, dealing with rust is a losing proposition and a waste of money.

Drive it and enjoy it. Try to keep from spending anything on it for a year or two if possible. Then buy a rust free car identical to it and keep the old one for parts. That rust isn't called cancer for nothing. Like cancer in a human, you can fight it, buy rarely is a full cure possible.

__________________
Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!

Retrive from salt duty, In your opinion, if the rust is fixed and the car is kept from driving in the snow ( which I can keep ) will the rust stop? what about light underbody rust? os there a treatment for that?

Rust will slow down considerably. If repaired well, it will take the rust over 15 years to start bubbling the paint, instead of one or two years with salt duty. This includes driving in the rain. I'm speaking from experience. I wouldn't worry about light underbody rust.

I believe salt is the root of all that is evil with vehicle ownership. I've always driven a summer-only car and kept another vehicle that I don't care as much about for the winter.

Elbow grease and POR15 / KBS stuff

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Does this mean that if you get a new coat of paint, that it would breach the factory surface treatments? I have been thinking of repainting my 87 260E for a while now. Because it's starting to show its age, and also some minor rusts are appearing here and there.

That rust spot in your engine compartment is probably from battery acid leaking at some point... I have seen it on many W126s on the internet.

As far as the other rust, its not bad. Our W126 is totally rust free, but its a southeastern car. When I was looking on the internet for one though, some of the ones up north were pretty rough and much worse than yours.

I have owned three Mercedes... 1985 380SE, 1984 190D and our current 1988 300SEL... thankfully all were southern cars w/o a speck of rust. When I listed my old 1984 190D for sale on the internet, I would get emails from people up north commenting on how nice it was to see a rust free older model 190.

Everyone so far has given some really good advice. Good luck with what you decide!

How I wish I had of kept this car! (but it could not hold a light to the room/ride of the 300SEL)

The last I was involved with Class A finish coatings, the following treatments and layers were involved for sheet panels:

- zinc, or zinc-rich coatings (either galvanized or galvannealed)
- phosphate
- E-coat primer
- color coat
- clear coat

When a panel is repaired, you lose the first two coatings, plus the efficacy of E-coating. I've seen and used phosphate solutions for bodywork, but I can't imagine that they are just as good.

If you do repair the panels, the corrosion resistance will be no better than with cars from the 50s and 60s. And we know how quickly those cars rusted. My dad told me stories of how wastage was so great that he had to have new rocker panels welded onto his 55 Ford every 18 months.

There is a lot of truth to the last statement.

There is one more layer on most cars, the primer surfacer. It goes between the e-coat and the topcoat. It allows you to sand w/o damaging the e-coat and provides extra UV protection to the e-coat.

Losing the ecoat is a problem. When you have to weld, you lose that coating, and there is nothing in the refinish world that prevents rust like e-coat.

Using high quality non sanding primers then sanding primers are your best bet to minimize the rust. Pretreatment solutions like zinc phosphate should help. Phosphates help bonding: just make sure you do not overload the phosphate. Phosphate to Phosphate bonding is very weak. That is one of the reasons using Rustoleum or other industrial coatings on cars. They have phosphate additives in them to prevent flash rusting and improve adhesion to untreated metal. The phosphates in the coating can actually interfere with adhesion to treated metal.

__________________
___________________________________________
2010 Toyota matrix

'93 500 SEL
A bad addiction. Takes all of my cash.

'12 Volvo S80 T6
Needed something that wasn't as hard to deal with as my bad addiction

'18 Mazda Miata
No more boring cars for everyday transport!