She's back on the road!! - PeachParts Mercedes-Benz Forum

pawoSD · #1 08-07-2009, 02:03 PM

Well, after days and days (some of them 12-13 hours of continuous work)....my SD is back on the road!! I finished it up last night, and did fine tuning this morning....and it drives perfect.

The original transmission lost reverse and then began dying quickly a few weeks ago, missing shifts, disengaging at random....bad sounds...etc.

So I pulled it off the road and swapped transmissions. I put in a 1985 300D transmission which required a tail housing swap (not too bad of a job)...it only had 163k on it, and it shifts great! The car has a whole different (faster and better!) feel with the 1985 high stall speed torque converter. It can really move off the line now!

I would not hesitate to say from 0-25 it is faster than my 300E....

I was able to pull off the task for less than 1/3 the cost of a rebuilt transmission, including buying: the trans itself, an engine crane (2 ton)...two separate orders of parts....and various cleaners and rags and supplies. I am quite pleased with that!

I took random pictures......they are all on my phone so I will load them either later today or on Sunday (leaving for a camping trip in a few hours)....

rs899 · #2 08-07-2009, 02:32 PM

It will be interesting to see what caused the failure on the old one- let us know what you find out. Hopefully you won't be scared of rebuilding it when the time comes ( or the '85) after you realize that there aren't any demons in there.

Rick

tbomachines · #3 08-07-2009, 02:46 PM

Nice! Definitely interested in the pictures and disassembly of the old one.

DeliveryValve · #4 08-07-2009, 04:33 PM

Good job. Did you make any adjustment with the vacuum modulator or kept it as is?

Glad it worked out.

pawoSD · #5 08-09-2009, 12:05 AM

Quote:

Originally Posted by DeliveryValve

Good job. Did you make any adjustment with the vacuum modulator or kept it as is?

Glad it worked out.

I adjusted the modulator about 2 clicks firmer....but it shifts great. The weirdest part is how the high-stall torque converter works...I just need to get used to it.

Eventually I will rip into the old trans....it is well past being saved. It sat in the rain with covers missing and such....not worth saving. Either way I will pull it apart and try to take some pics/see what happened.

I am guessing that a clutch disc failed or something....based on the chunk of metal I found in the pan, and the clumps of gray silt/clutch material.

bsmuwk · #6 08-09-2009, 12:35 AM

So that morning drive was definitely worth it eh?

Now I just have to find a buyer for that gem of an engine.

Oh and by the way, when tearing into your old transmission, any bad clutch disks will be an almost blue color, almost like they've been bruised. When you're tearing into it, make sure you have a nice space to work in and put the transmission guts on.

Trust me on that. You'll need all the space you can get if you're going in for the first time.

pawoSD · #7 08-09-2009, 01:19 PM

Quote:

Originally Posted by bsmuwk

So that morning drive was definitely worth it eh?

Now I just have to find a buyer for that gem of an engine.

Oh and by the way, when tearing into your old transmission, any bad clutch disks will be an almost blue color, almost like they've been bruised. When you're tearing into it, make sure you have a nice space to work in and put the transmission guts on.

Trust me on that. You'll need all the space you can get if you're going in for the first time.

If I tear into it, I won't be intending to put it back together, so I'll probably just dump parts in a bucket.

That drive was indeed worth it! It works beautifully.

Thanks again!

pawoSD · #8 08-10-2009, 10:46 AM

Here's a few pictures of what I found in the pan when I took it off of the old transmission: One edge is smooth, the other jagged like it broke off.....what is it from?

New bowden cable installed on new transmission, its actually quite easy to replace...

New wastegate hose (they're expensive!

) for the motor....it had needed this for a while:

Nice shiny bowden cable adjustment:

A/C compressor delete: So far this year we've only had about 4 days over 85 degrees....no need for A/C here

Neat shot of the exhaust turbine in the turbo....

That's about all the pics I took, I was working at a vicious pace to get the car done by the weekend, so little time to stop and take pics. It drove beautifully this past weekend on my camping trip....have put over 220 miles on it so far!

rs899 · #9 08-10-2009, 11:15 AM

The mystery piece of metal looks like about an eigth of a retaining "spring" from one of the clutch packs. The other 7/8ths of it may be floating around inside somewhere, causing havoc, or maybe that clutch pack is now very loose, causing the problems.

Rick

pawoSD · #10 08-10-2009, 11:54 AM

Quote:

Originally Posted by rs899

The mystery piece of metal looks like about an eigth of a retaining "spring" from one of the clutch packs. The other 7/8ths of it may be floating around inside somewhere, causing havoc, or maybe that clutch pack is now very loose, causing the problems.

Rick

Interesting, makes sense, since 4th gear and reverse were in the worst shape when it was still in operation....4th was always questionable on that trans though, it did not have a "firm" engagement....it'd require letting off the throttle to get it to engage.

The new trans firmly shifts into each gear, its awesome.