I did not find many pics of the inside of these 716.210 4 speed manual transmission. I had to replace 2 brass synchroniser rings: 3rd and 4Th speed rings were broken. I bought the car like this from the previous owner. The tranny was still working fine (!) with the "double clutch" method (second to third and third to fourth). First gear to second was OK...The key was to replace the synchros and after a road test, everything is now perfect! Like a new one! Cost for each synchro is $50 CDN.

HDen

Attached Thumbnails

     

__________________
W126 1985 300SD TurboDiesel
W164 2009 ML320 BlueTEC (Sold)
W123 1983 240D Stick (Sold)
W210 1998 E300D TurboDiesel (sold)
W124 1993 300D 2.5 Turbo (sold)
2012 GMC 2500 Duramax PickUp
2015 Ram 1500 EcoDiesel PickUp

WE ARE NOT WORTHY. How hard was it to disassemble the tranny? Just take off the end piece? Did you have to pull the gears to get to the synchros? I have found zero info on rebuilding these. My 1st to 2nd is shot.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Fifty canadian for a new syncro ring is not bad. There is some coverage in the reasonable priced haynes manual on standards I think. Although I do not think you really require a manual to change one. It is fairly straightforward on these I believe. I just had a look and there is probably enough information in that low cost manual to get you by as well if needed.

The Real McCoy can be downloaded here:

__________________
Never a dull moment at Berry Hill Farm.

now that is a whompin pdf

oh and look at all the goodies in the parent directory.... i am officially leeching as we speak. wget -r is a wonderful thing

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Don't go there...

__________________
Never a dull moment at Berry Hill Farm.

Does anyone know the price of the plate wear gauge? 115 589 07 23 00

The 1st to 2nd synchro ring is located "close" to the rear cover of the tranny. See pic from my first post. The 2 rings I had to change were at "the bottom" of the box when we look from the rear end. That's why I had to remove the whole shaft. I don't think you need to remove the shaft, but i'm not sure Just remove the gears one by one in order to get to the brass synchros. A few snap rings to be removed. Make sure the get new "clips" that retains the synchro to the gear (Item #109 and #127)

It's not hard to dismantle the tranny, but I took my time! It's winter here and I don't need the car. In order to remove the shaft completly, I had to remove the cover in the housing (pic Housing1) and also the upper shaft and the snap rings (pic Housing2). The lower shaft (countershaft) didn't have to be removed.

Maybe your job can be done without removing the tranny from the car?? Just remove the rear cover etc...That would be relatively "easy" but not sure if you will have enough room to work. This way, the slave cylinder may stay in place and you will not have to bleed the system. Good luck!!

Attached Thumbnails

     

__________________
W126 1985 300SD TurboDiesel
W164 2009 ML320 BlueTEC (Sold)
W123 1983 240D Stick (Sold)
W210 1998 E300D TurboDiesel (sold)
W124 1993 300D 2.5 Turbo (sold)
2012 GMC 2500 Duramax PickUp
2015 Ram 1500 EcoDiesel PickUp

Nice work.

My 115 has a crapped-out 1-2 synchronizer and, I have another 4-speed (spare) with a trashed final drive spline and spider. One of these days...

__________________
Never a dull moment at Berry Hill Farm.

Cool thread. Thanks. My 2nd into 3rd is pretty bad. One of these days I hope to be able to get into it and do this stuff myself.

- Peter.

__________________
2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S

Oh my god, you guys are life savers.

I just done a transmission swap in my 300D coupe turbo, and found 2nd gear to be synchro bad :'(

4 speed manual from a 300D

I'll get the Box's part number when the sun is up, but do you guys know the part number of the synchro for 2nd gear please ?

Attached Thumbnails

 

math:

The box in the posts from almost 12 years ago is not the same as the one you are having a problem with.
What oil do you currently have in your box? If not ATF, that may be the problem. Before a teardown, try using Type F ATF.

oh okay, they look the same to me

w123 4 speed manual.

I was using ATF, before putting the box in it's place inside the car, i had it on it's side and filled it with ATF ( maybe too much ? ), not sure what type though, i thought there was only 1 type ?

Here's a link to what i used

https://www.castrol.com/en_au/australia/products/cars/automatic-transmission-fluids/atf-dex-iii.html

The grinding synchro issue is only when trying to shift into 2nd gear. 1st, 3rd and 4th are fine.

You cant use DEX III in a old mb tm they use ATF type A. DEX III is too new I guess.

I live in Canada so things may be a little different here. Type F transmission fluid is available here from tractor dealers.

I do not remember seeing it on the shelves of chain stores reciently. Then again I am not buying much automatic transmission fluid. So I just might have missed it.

Also it might be more commonly available in American outlets. It kind of makes sense at the sane time as nothing current that comes to mind takes it I can think of.