My 1982 300SD Project Thread

[Mölyapina]

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.):

As a few of you already know, I bought my second car on Saturday – a white 1982 300SD . I bought it from a fellow forum member, tbomachines (Tom). The shell is a Texas shell. It’s original story is unknown, though I may try to track down the hands that it passed through when I have some spare time. Tom bought it a few years ago from another forum member who had taken the drivetrain out and was storing the shell in a hangar in New Jersey; Tom took the drivetrain out of his old, rusty ’82 (“Boxy Brown”) and transplanted it into this one. He then drove it regularly, replacing the tires, brake pads, calipers, and discs, glow plugs, motor mounts, filters (including power steering thingie), Battery, flex disc & hardware, water pump housing, thermostat, etc. along the way. Then, last fall, he tried to pull away from the filling station only to find out that the transmission would not engage in Drive. He then attempted replacing the B2 piston, but to no avail, leaving him to conclude that the B2 band itself was bad. He priced out some trannies, but didn’t have the time to fetch one or install it, so the car ended up sitting in Connecticut, doing nothing but killing grass & running occasionally (thankfully, Tom started it periodically & pushed it back & forth to keep the tires from flatting) until I went down this last Saturday and bought it. It was then towed to my home in Chelmsford where it sits today. The paint is very nice, and the body is TOTALLY rust-free with the exception of EXTREMELY minimal rust on the undersides of the fronts of both rockers and a hole under the battery. The car starts faster than our 2004 Corolla with 145,000 [EDIT -- at 149,500 as of today; keep marching, old soldier!]. I plan to put the transmission from my 1984 into this thing -- I will swap tailshafts, of course. Here are some pictures – I also have some questions which are listed below. The blue car is the ’84.

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.

[Mölyapina]

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.

[Mölyapina]

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



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.

[Mölyapina]

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:



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.

[Adriel]

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

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.

[Mölyapina]

More pictures on the speedometer/odometer project:

The W126 cluster -- the big white monster in the middle is the speedometer.


The W123 speedometer/odometer -- clearly very different . It looks horrid, but it works!


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.


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

[Mölyapina]

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

[Adriel]

Originally Posted by Jooseppi Luna

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.

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

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!

Hope you get a lot done today!

[crazy4diesel]

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

[Mölyapina]

Originally Posted by jake12tech

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.

Thanks! The paint does not look as nice in person, though overall it is more than decent. I have some cracking on the rear doors which I'm going to have to address.

Originally Posted by crazy4diesel

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

Yeah, this speedo came with a chrome plug, and the other 'SD instruments have black plugs, so I was going to look for a black plug... wait a minute,I just had a thought... could I grab the other chrome ones from the W123 cluster? I bet I could...

That would look "classier". Thanks for jogging my mind a bit!

[JB3]

did you get your starter installed?

[TnBob]

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

[Mölyapina]

Originally Posted by TnBob

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.

[Mölyapina]

[EDIT]Reading this through, I notice that it contains copious amounts of rambling. Be warned...[/EDIT]

The starter is going in tomorrow. It's for the spare engine -- after spending about two hours trying to pull the starter from the 'SD, I gave up and rang up MagicBus and got a great deal on a used starter! I'll bolt it on to my spare engine tomorrow so that I can pull compression numbers and put it up for sale... then it is back to the 'SD . I'm estimating ~3 hours of work to get it drivable -- very exciting!

Ironically, it was last Thanksgiving break that I was planning on getting a lot of work done on the 300D that the tranny for this 'SD came out of... however, my sister & I were hit the night after Thanksgiving by someone running a stop sign at about 20-25 MPH and I was not able to work on any car for the next several months due to back & neck injuries and a concussion.

I still remember the accident. I see a late-model Honda Civic coming up to the stop sign not yet braking (he is coming from a side street), but I assume he is just going to do his braking at the end. Only when I am too close to stop does it become clear that he is running the sign... I floor it, swerve into the oncoming lane (no one is coming), and blare the horn. I still experience the scene, the headlights cutting a path ahead of me, the engine running hard as I am flooring it to get away... a sense of relief when I think I have avoided him... and then a deadening bang... and it is over.

We are sitting in the lane we were traveling in, facing a Civic with a now-busted front bumper.

Ugh.

[Mölyapina]

So, the good news first: the only things left to do on the transmission end are the shifter linkage hook-up, driveshaft center nut tightening, and ground cable install! I got the flex disc/driveshaft thing bolted up today, the TC & FW bolted up, the dipstick installed, and a bunch of other misc. done. I'm very excited.

Bad news is this:



That's the passenger's-side rear outer. Thankfully I caught this before I drove on it. Here are the other three, going from passenger's-inner to driver's-outer:







I'm thinking of popping an Astoria on the busted one and waiting to do the others until Christmas break. Does that sound like a good plan? I'm thinking of going this way because I'm hoping I could replace the outer boot without removing the axle from the diff. Is this correct?