Coating rust w/silicone will def. NOT keep rust from spreading, and MAY accelerate it.

Get the silicone off, clean the scale off as best you can and by a product such as "Extend" for neutralizing rust. Once dry, prime and paint. This will help, slowing down the spread as much as you can without a real repair.

__________________
Chief

1991 350SD

@chief . . . my sentiments exactly. One can buy OSPHO at a Marine store, just keep painting it on til it stops showing through red. Add 1 extra coat, or as many as you need to have enough left after sanding smooth (as a primer), then shoot paint on top of it.

__________________
1983 300D, the "Avocado"
1976 240D, 4-spd the "Pumpkin", SOLD to Pierre
1984 190D, 2.2L, 5-spd, my intro to MBZ diesels, crashed into in 2002

You really scored with those bumpers! Nice looking little car. I love the euro bumpers with the paint match hubcaps.

I have read before that silicone will promote rust because of some ingrediant in it.

I had a rust issue in the 85 along the lower pinch weld under the rear glass.
removed the glass, used Jasco paint stripper and stripped the paint 1/2 way up both sides. used POR Marine clean to wash it clean, then treated it with POR Metal ready on the rust, and it also etches the bare metal for better paint adheasion.

Then coated it with 2 coats of the POR paint, and covered the pinch weld with some thin fiberglass cloth. coated it with the paint, and this seals the pinch weld. also used POR Seal Sealer, and applied it with an Acid brush to areas that gave me some concerns.

Follow their directions and you can`t go wrong. then give it a shot of your favorite color. time consuming, but worth it.

Get a new gasket and install the rear window.

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Great, now I just need somebody who's willing to help me take out and put the windshield back in since the hubby thinks doing it ourselves is a Bad Idea

OSPHO pretty much does the same thing as POR15 then, right? Does it matter which one I use?

__________________
1983 240D, 272K+ miles (odo broke)

It IS a bad idea to do the glass yourself.

IMHO, if you want to preserve the car really well, and are willing to remove/replace the glass and do a new gasket, you should be prepared to do it the right way.

Once the glass is out, you can assess the metal. It may be that it can be repaired by a good body mechanic, or a section cut out and replaced with a good section from a donor car. This is not rocket science, so don't let that scare you.

If that all sounds like more than you want to put into the car, then you can go the Ospho/POR15/Extend route, stoping the spread of the rust, and adding some sealer if needed. Everyone has their favorite commercial product to use, but I would suggest using what you can find locally and inexpensively. I have always liked products like Extend because you can find them at every hardware store, it's cheap and it works. This is only a repair to keep the car on the road, keeping the wolves at bay, so to speak.

__________________
Chief

1991 350SD

And OSPHO (like Extend) is a phosphoric acid compound, that "kills" rust. The treated metal must then be coated with something like primer and paint that will cover it and protect it from the elements. The POR15 that is usually referred to is a black coating that is frequently used on floor pans and chassis.

__________________
Chief

1991 350SD

Several of us on this forum have replaced rear glass by ourselves and are relatively comfortable with it. But, it's not for the faint of heart. If you are going to attempt one, I would at least locate (or buy) another piece of glass at a junkyard for a backup. It's a real thin piece of glass with a fairly wicked curve in it. It my be hard to find professional help by now, too, unless you can find an old-timer who has done these.

If you really have rust down in the channel and you want to keep the car, you really need to think about this. The best way to kill rust is to grind away to white metal, use phosphoric acid , prime and paint.

__________________
80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)

POR15 and OSPHO generally the same thing, except maybe in smaller, civilian-use quantities. DO NOT OPEN UNTIL YOU'RE READY TO USE, BECAUSE IT WILL START TO HARDEN IMMEDIATELY, and you will open it up two weeks later to find it's hard as a rock. Several companies have put it in 8 or 16 oz sizes, for the average home/car use because of that, or if you have lots of work to do with it, you can buy quart size, or larger. We used to order by the gallon!!!!

Also, OSPHO is recommended for use as a primer, but it will be in black, so if your primer is supposed to be white, you may wish to do a coat with the white stuff afterwards.

Hint for the windshields:

Based on my experience in the "old" days on R&R windshields/windshield seals.

Get:
thin rope or string
a bar of soap
And extra set of hands

You'll have to find out from others if the chrome trim on the windshield must go on the preformed rubber track before, or after installation of the seal/windshield. Generally, it goes on before, when you have more control and can bend the seal, instead of prying to open/close the trim. However, when my front windshield was replaced (for free under FL law), they put the trim on last . . . but the guy doing it had to call an old geezer to help him, as he had never done one of the older preformed seals.

After you removed your windshield, taking care to carefully disconnect the power to the defrost grid, pull the windshield away from the car, place on sawhorses for prep. Clean up the track on the car, taking care to remove and neutralize rust. Let any primer/neutralizer dry. Put the seal on the window, being carefull not to snag the connection for the defroster grid. Run the string around the inside of the lip for the seal that goes onto the window frame. Also coat the window track and the rubber with the soap . . . will make it slippier!!! (??? sic)

The start folding the rubber over the edge to get it started. Then use the rope/thick string that is in the runner to continue the lift/pull of the gasket to go over the window track . . . .have another person outside the car gently pushing the window to help seat the gasket/window. After you have seated the window on the track, use a plastic scraper to help lift the edge to put your sealant in it, to insure a leak-proof installation.

__________________
1983 300D, the "Avocado"
1976 240D, 4-spd the "Pumpkin", SOLD to Pierre
1984 190D, 2.2L, 5-spd, my intro to MBZ diesels, crashed into in 2002

For giggles I called around to get price quotes on a valve adjustment. Dealership quoted me at $240. Salim's Silver Star (a place in town that works exclusively on Mercedes) quoted me at $110. Well gee...=P

__________________
1983 240D, 272K+ miles (odo broke)

This is one of those jobs that seems intimidating at first but it's really simple and easy. I highly suggest getting the wrenches and doing it yourself. Invest that money that they want to charge you and get the wrenches, then you can always do it your self and save $100-$200 everytime. I can do my 240 in about an hour. I've done it several times though, the first time always takes longer. I bet you could find a guy local to you that would be happy to help out.

__________________

Ok, I wanna change out the power steering fluid. I have a new filter in hand, now I just gotta buy some Dextron, as someone upthread recommended. But how much do I buy? I've never done this before. Should one quart be fine?

__________________
1983 240D, 272K+ miles (odo broke)

Here's a fresh thread - Power steering hoses/flush on the 87 300D

If there's no history of PS fluid service, get a gallon of cheap ATF for flushing.

Sixto
87 300D

I'd been eyeing the how-to on Diesel Giant.

Mercedes Power Steering Fluid Service

Should I disregard this, then? Or would it be ok to follow the suggestion outlined at the end of post #12 in the topic you linked?

__________________
1983 240D, 272K+ miles (odo broke)

You can replace the fluid in the reservoir or replace just about all the fluid. Your choice. It only costs time and a jug of ATF to do a more thorough job. What's frustrating about not flushing is the fluid looks yucky again after only a few miles.

I wouldn't disregard the good advise of DieselGiant, only his recommendation to use Dextron

Sixto
87 300D