in 2 hours I'm going to look at an '85 300SD with 140K miles. The car hasn't been run in a week or so so I'll get to "cold" start it....I've read the "is it a dog" article on buying a used 123...Can anyone give me any other tips on what to review? Supposedly everything (AC etc.) works has mint interior and cosmetic rust...we shall see....

Where can I learn more about the differneces between the 300D and the 300SD?
Rob M Concord, MA

First not to be rude but do a search I don't think their is anything that has not been covered on the W126 or 617.

But the 300SD is a pretty simple car just drive it and make sure it handles right, the oil presure is good ect. Also look for rust, under the rear window and the jack points are big points.

Is their a maintaince history? Ask the owner when the valves were last adjusted, they should know. I dont like "the valves don't need adjusting" or "never". If they neglact the simple stuff what other things are hiding?

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

OK I just figured out the SD is a 126 no? so is this way more complicated than a 123 or what???

No offense taken, sorry to ask general questions but I DOH! just now figured out that the SD is a 126 and most of my reading has been associated with the 123 platform....Thanks for the info.
Rob M

As one who has just made the jump from W123 to W126, let me give my impressions.
The cars obviously share a design philosophy. There is much in the W126 that looks very similar to the coresponding part in W123. The W126 is a little larger. I just discovered the hood and trunk are stamped in light alloy, not steel.
There is little interchange of parts between then other than the diveline. But the suspension and body obviously came out of a common mind. The W126 is a much more refined car.
The downside is that there are far fewer W126 in the junjyards for parts picking.
Keep us posted about what you find.

Results of review of '85 300SD with 140K
- front jack points had ~4"diam through hole of rust around them.
- top surface (chrome) of front bumper had several small through holes of rust
- very slight surface rust at top underside (interior) rim of trunk
- a few spots of rust at a few of the corners where the lower bosy cladding (plastic?) meets the body
- No opportunity (yet) to review records
- coolant in resevoir appeared fresh
- injection pump area void of visible fuel
- small (1-2mm?) vac tube appeared to be burnt by what I'm guessing was the egr cooler? - located at front of engine bay alloy pipe (with bellows for flex) which appears to carrry exhsust gases - Any idea what that tube would be for?

- all windows, sunroof, door/trunk locks operable. passenger side mirror electrically adjustable with switch between seats (is the drivers mirror similarly equipped?
- from a "cold" start it started immediately wioth no evidence of smoke.
- after post test drive shut down slkight oil mist/vapor visible under oil fill cap but no "puffs" or clouds....
- squek from what seemd like the power steering pump throughout the test drive, even after warmup....

Whaddaya think? Thoughts, musings, concerns?

- interior in VG conditions no dash cracks, power antenna works, afgtermarket radio installed, no wetness apparent in floor pans/trunk

stayalert,

Remember, rust is like an ice berg, you only see 1/7 of what's there.

I wouldn't say the car you are looking at is in "good" condition because of the rust. Possibly it is in "fair" condition.

So you have to figure if you want it and what's its worth to you.

I paid top dollar for an '87 300SDL with out a scratch, nick or spec of rust, but it was worth it to me to get one in mint condition.

P E H

The car depending on their asking price sounds ok.
The rust on the front bumper chrome is normal either find a used one or MB offers new ones for $400. Now if I am reading it right the jack points are solid and just have some surface rust on them? If so thats not a big deal to take care of. Also it sounds like the rear window will have to come out to fix that rust. Was the rust coming out from under the gasket? Rust starts behind the body clading you will have to remove it and see what you find. But doors are cheap I wouldn't worry to much about that.

Also in the front wheel wells their are two spots you should check:
Where the sway bar comes out
The frame rail in the back of the well.

Squek from ps pump could be a belt the 617's used a few fan belts. Rebuilt pumps are not to expensive either.

How are the maintaince records?

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Be very picky, Your going to pay alot. Take it to a reputable Indy and have him inspect it for you. He may save you $$$. If you have records on the car it'd be great. If I was going to spend alot of money on a fine Mercedes, i'd look for one without rust. I did the same with my '86 300 SDL. I paid the high end, with no rust etc.

If I have learned only one thing form my SDL it is this:

"the most expensice Mercedes is a cheap one"

My next W126 will be a mint southern car and I will not flinch spending $10k+ on it. I am done with buying beat junk.

stayalert not that the one you are looking at is junk but just another way of looking at things.

What are they asking for it anyway?

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

"there's nothing more expensive than a cheap Mercedes" has pretty much become my (repeat to self when looking at cars) motto....asking price is $3,200 has 2nd tank sytem for burning grease installed, which is worth some $ if that's wahta you want....I like the two tank system but in some ways would rather install my own after living with the car ans sorting out the variuos things that are bound to be out of whack/in need of attention....

I'm currently in no rush and will continue to learn more about this car and other prospects. In some ways I prefer the 300D to the SD but am to the left on the learning curve and have only driven one of each.

Thanks and keep the thoughts and comments coming...Rob M

Think of the W126 as a big more refined W123. The W126 is no more complex than a W123 unless you get a 560SEL. But even those are not to bad. The only big difference I can think of off the top of my head is the W126 has an electric vac pump in the spare tire well. Just drive a few and get what ever one you like better you really can't go wrong. You could also try a 300SDL. The 603 is a pretty sweet engine.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200