In my nearly 10 years of Mercedes dieseling, I've always dreamed about having a manual transmission backed 617 turbodiesel. Mercedes never made a manual 300SD, or brought any manual transmission 5 cylinder diesel cars to the US, so finding one stateside is like finding Sasquatch.

You can swap transmissions from the relatively common 240D 4 cylinder, but I've heard horror stories about drive-line vibrations due to the flywheel not balancing well to the larger motor. I never went through with a swap project because I didn't want to ruin a perfectly good car due to poor execution or missing parts. That all changed last week when ghost of Rudolph Diesel smiled upon me, and this car was listed for sale.



It's a complete US spec 300D with a EURO-market 5 cylinder 300D manual transmission setup successfully swapped over, and several years of happy gear rowing under its belt. It was the perfect candidate to cannibalize for my 1984 300SD, a turn key setup I could reverse engineer to my larger chassis car with only a few modifications.

Now you might be thinking this poor little China Blue W123 is too damn nice to rip out its hope diamond and swap into my 1984 300SD. Based on the description I was even reluctant, but you have to remember one fact. All sellers of old Euro cars are liars. They either lie by omission, ignorance, or downright deception. In this case it was all three.

The car was described as having no rust. In reality this car has terminal rust in several obvious areas including the door bottoms, lower fenders, and along the back window. In addition to the damage disclosed on the driver's side, the hood was rippled like a couple of chubby teenagers were laying on it while trying to make second base.

Mechanically it was a basket case as well. The turbo didn't spool up, battery was not charging, window regulators dead, climate control totally F*#&$, and the list goes on except for the part that mattered to me. The transmission shifted fantastically. Even in the battered car it felt amazing. The executives at Mercedes were idiots thinking more manual transmissions didn't belong in the US. So with zero qualms about murdering the donor car, work was started today on the swap.

First let me introduce you to my 300SD receiving the swap. I purchased it nearly 2 years ago from a dealer friend of mine who found it at a wholesale auction in Dallas. It was traded in by the original owners for a Mini-Cooper. In the trunk was complete documentation spanning 30 years, from purchase details to every last oil change and repair. It is in fantastic original condition inside and out and by far the nicest Mercedes diesel I have ever owned. There's a thread documenting the last few years here. Here's a photo from Cars and Coffee last week next to my S600.



Today my mechanic assessed the project and tore out all the components needed from the 300D. It's missing the nose and some other bits for another project.







He also got started on the 300SD, removing the brake pedal assembly and adapting the mount for the manual pedals.





The only part I've ordered so far is a speedometer from a 1989 300E. I needed a cable driven speedo that can be adapted to fit in the all electronic 300SD cluster. The 1986-89 300E have the same size speedometer face and share a similar rear differential ratio so the speedo reads accurately. Once everything is put in, the driveshaft can be measured and modified to the right length by a local shop.

My Mercedes diesel wet dream is coming true.

__________________
1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!

Nice. Best of luck with the project. Out of curiosity, would you mind divulging what you paid for the 300D?

I have a pedal assembly for a 126 body for a stick.

Really that car is so nice I suggest you hold out for a five speed!

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

$2200. Wow yeah I know, BUT! I needed lots of stuff to finish off my 240D to almost mint shape. About $800 worth of stuff. I also need the power steering pump and glow plug relay for the 300SD. He wasn't budging on the price and when was something like this ever going to pop up again?

And I have already sold the rest of the car off for a decent chunk. The motor sounds fantastic and it does have many good parts.

__________________
1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!

Thanks, looks like this one adapted well.

If a 5 speed ever pops up in my lifetime, I can swap it out. Wouldn't take much doing.

__________________
1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!

No need to justify it. If you end up happy, that's all that counts. Besides, it sounds like you're already bringing that number way down by selling stuff off the W123.

No change in driveshaft length?

I wonder if the 4-speed would be happy with a 2.88 rear.

You probably meant 5-speed 617s but MB sold a bunch of 190D 2.5 5-speeds.

Sixto
83 300SD

That looks like a great project.

I was tempted to swap my 240d trans into my 300sd but I had too much on my plate when I sold the 240.

A rebuilt auto made more sense since my wife cannot drive a manual. FWIW I paid $2300 for my rebuilt 722. You're way ahead.

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles

Not sure about '84, but I know that in 85 the end of the crank was different and it is difficult to get a pilot bearing to fit. As far as I know, the correct size does not exist. I had to get the outer shell of the stock bearing ground down very slightly at a machine shop to have the proper fit.


Sent from my iPhone using Tapatalk

__________________
1985 Euro 300TD Turbo

Yup, bearing needs a haircut on this one as well

Attached Thumbnails

 

__________________
1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!

I have a 2.88 diff and speedo I'll sell reasonably.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

TH:

Should you be interested, I can supply a copy of the flywheel imbalance matching tool, as illustrated in the FSMs.
Available for loan or purchase.

Shameless plug, for my 717.400 trans car for sale. in a 240d but still 5 speed.

I always wanted to do this also, too bad things get in the way, illl have to live vicariously through you AND build a toyota pickup with a 617.......

Good luck with the build, it sure seems like you are the right person for the job!!

__________________
1983 240d 5Sp SOLD
1986 300D(LUCO) SOLD
1983 300TD(dreamboat)SOLD
1984 240d (Executive)SOLD
1984 240d (Euripides) SOLD
1982 300sd SOLD
1982 300sd (Ambas)SOLD

Well Tyler, you will love it. My 240D with 617D Turbo is the best thing since good instant coffee. I am getting old and the work is very difficult now, but there is a pretty nice SD for sale here in IN and I am tempted. But I absolutely love driving my 240D, it is fast an so comfortable. I don't have A/C in it now, but I am kind of planning to go to Phoenix this winter and have a total new system installed.

__________________
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!

Darned shame you already sold the rest of the car. I've been looking for a 300D turbocharged 617 for my '81 300CD project.

__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now