My 1982 300SD Project Thread
 

So, where to start? I guess I should first start by reprinting the introduction I gave to the car when I bought it in May (feel free to skip down to where I talk about what I'm doing now; most of that is background on the car itself.):

So, I just pulled engine and the tranny out of my parts-car 300D and am now working on getting the tranny into the 'SD. My first step has been attempting to modify the speedo from the 300D so that it will fit the 300SD. Everything is working well so far -- I will try posting pictures tonight. I will also be converting the car to manual seats and Delibes has said that he will be able to get me manual seat trim for the W126 next time he is over in Europe -- yay -- so it will look morealess factory. I got two free seats with very nice bottom cushions for free from JB3, so I will be swapping skins and have a matching interior with simplified, comfortable seats.

OK, so stuff has happened with the car :). We have the transmission bolted up to the engine, and I might even be able to run it tomorrow if we finish everything up (!). Things remaining to get done are as follows:

1) Hook up the tranny fluid dipstick.
2) Double-check the tightness of the tailshaft nut and bolt up the driveshaft.
3) Bolt the FW to the TC.
4) Reinstall valve body & hook up Bowden cable, replacing the filter and pan gasket at the same time.
5) Fill with tranny fluid.
6) Finish bolting up starter.

Then it should be driveable! I will be focusing my attention on selling my spare engine after that, and then I'll have enough $$ to register the car.

These came in the mail from mikethezipper yesterday. THANK YOU MIKE THE ZIPPER!!!

http://img.tapatalk.com/d/13/11/09/jaduve9y.jpg

They are Bilsteins for $40/pop for the rear. These will be installed after the speedometer is completed (post coming), the interior is finished to the point where it seats five, and the rear driver's-side window regulator is replaced.

OK, the speedometer. Since the tranny I am swapping in is from a W123, the transmission tailshafts are not identical because the W126 has an electric speedometer while the W123 has a mechanical one, and the speedometer is fed from the tailshaft. There were two reasonable ways to solve this problem:

1) Swap tailshafts. This IS possible going W123 (transmission 722.315) --> W126 (transmission 722.303) but IS NOT possible going W126 --> W123 because the mechanical speedometer needs to fed tranny fluid from a special line coming from the main body of the tranny that is not in the 722.303 because it does not need it. Despite the fact that I could have gone this route, I chose not to.

2) Put the mechanical speedometer from the W123 into the W126 cluster! This is a bit more difficult than it maybe sounds because the clusters are very different. However, going on Charlie's thought that "with enough hacking anything is possible", I poked ahead and it turns out that it's actually not too terribly difficult to fit it in. Here is the partially modified speedometer:

Attachment 116595

I trimmed the bottom of the speedo to squeeze the face into the cluster, and the one other thing that I will have to do is trim a little bit of metal off of the backing plate -- the steel cup that the speedometer/odometer mechanism sits in. The top is just a little bit too high for the W126 cluster.

Here comes my question: how should I take this metal off? It looks to be about -- oh, I don't know -- 1/8 of an inch thick? Should i use a grinder? A saw? What do you guys think? It's a very thin length all across the top, so I was thinking of using a grinder, but the only hitch is that I don't have one (rats). I'll get a better picture up tomorrow morning.

Jooseppi, glad to see you are getting a lot done! :D

Interesting way to make the W123 transmission work in a W126! Too bad the tail cone swap doesn't work.

As for trimming, I would tape a piece of medium grit sand paper onto the work table and rub the edge down until a perfect fit.

I suggest you put the Dremel 3000 on your wish list! ;) It is the best power tool investment I have made! Sliced off the rusty stud so I could remove the battery tray and removed loose rust scale. Hope soon to buy the attachment kit, get some polishing compound, and correct the scratches the body shop put on the mirror glass. What I love most is that variable speed so doesn't scare me and go to fast to where I do damage. :D

More pictures on the speedometer/odometer project:

The W126 cluster -- the big white monster in the middle is the speedometer.
http://www.peachparts.com/shopforum/...1&d=1384002867

The W123 speedometer/odometer -- clearly very different :). It looks horrid, but it works!
http://www.peachparts.com/shopforum/...1&d=1384002867

The two together. The bottom of the W123 speedometer has been trimmed to fit. I'll have to figure out what to do about the turn signal bulbs.
http://www.peachparts.com/shopforum/...1&d=1384002867

Fitment of the W123 speedometer into the W126 cluster. You can see the part that I need to trim off.

http://www.peachparts.com/shopforum/...1&d=1384002867
http://www.peachparts.com/shopforum/...1&d=1384002867

Adriel, thank you! I'm SUCH an idiot -- totally forgot that I have a Dremel! I can use that.

Jooseppi, you are welcome! Glad I could help. :D

I can beat that: I apparently tossed out the mono-valve I bought! :silly:

I always unpack parts and put them in the bin. However, I didn't unpack it so it wouldn't get damaged, but swear I put it in the bin. I have torn this place up twice, last night and this morning, and nowhere to be found! Oh well! It is what it is! :cool:

Hope you get a lot done today! :D

Oh my! About two days after my 1984 300D had been hauled off to the yard (after I thought I had totally stripped it), I realized I'd forgotten to take out the speedo cable -- which I obviously need! So I called the yard. It went something like this:

"Holland Used Auto Parts!"

"Hello, I had a car hauled off to you guys a few days ago -- a 1980s Mercedes. I realized afterward that I left a part on the car that I wanted. Is there any chance it would still be in the yard so that I could come buy the part?"

"Uhh... yeah, it should still be there."

"Oh, okay! Uh, it did come in with no doors, do glass, no drivetrain... I mean, it was stripped. So even that would still be there?"

"Oh hahahaha yeah I remember that car. That's gone -- we crushed it hahahaha"

He seemed very amused by the memory of my car :D. I got a kick out of it.

Taking a break from putting the valve body back in -- going out to finish it now, hopefully before it gets dark...

Wow, that's the nicest SD I've seen in awhile. That paint is amazing after all these years! My 126 was Cabernet Red. Drive that baby till the wheels fall off! I plan on getting another W126 real soon. :cool:

Jooseppi, guess you didn't see the other thread I made because I found it...

Bummer on the speedometer cable! But, at least the only thing you forgot. ;)

Hope all went well! :D

Dunno about you, but the missing black plug on the needle of the speedo would drive me nuts down the road.

No problem with your turn signal lights, the 123 cluster has two lamp sockets for them

True -- I'll probably jut graft those into the W126 cluster somehow.