Torque Converter Questions
 

I picked up a 1983 300D Euro model for $200 yesterday. I got it home last night and pulled the tranny today. I now see why nothing worked; the tabs on the torque converter that run the pump were both broken off.

My question is, what could cause those tabs to break? Pump seizure? :confused:

I have another TC I can try but I'm afraid it will break too. Any thoughts?

THanks!

This is a "known problem" for the 722.1 transmission - but by 1983 I'd expect a 722.3 to be fitted even in a Euro spec car...

Which transmission have you got?


Very basic question => Do the input and output shafts still turn?


Which ever transmission you have I think it is a good idea to have a look at the front pump - like remove it and see if there are any wear marks / signs of over heating / seizing...

I've posted up some pictures of the front pump in a 722.118 here

http://www.peachparts.com/shopforum/diesel-discussion/304903-722-118-automatic-transmission-rebuild-monster-diy.html

The Euro-300D N/A had a 722.118 transmission until June 1983. From July 1983 a 722.405 transmission was installed.

Tabs can break if the torque converter wasn't installed properly. If the tabs break during normal operation, it can be caused by pump seizure or when the flywheel isn't straight anymore, although this would usually cause some other damage too.

Army - Here are the numbers from the Trans that is in the car 115 270 17 01 024098 which, from what I've found, is a 722.118. I don't think it's the original transmission:
1) It has kickdown? linkage going back to the trans
2) The throttle linkage is all "goat roped" together (similar to Jerry rigged)
3) Two injector lines have been bent to make the goat roped linkage work.
4) The IP has two vac ports with nothing on them (See Photo). What is that thing?

Do you think the PO put in an earlier trans, added the linkage and removed the vacuum parts?

Dan you've got yourself an M injection pump there.

The 722.118 was a vacuum-only transmission on a 1983-300D. The transmission has been replaced by an older, non-vacuum one, one which is controlled by the throttle linkage.

Go Army! Great write up on the rebuild! I'll send you some 100w light bulbs:D

Govert - That's what I figured. Thanks for confirming!

Now, I do have a spare 722.118 that came out of a 1980 300TD. It is the vacuum operated model. Are those two vacuum ports on the IP related to the trans operation? I'm going to put it back to the way its supposed to be.

I guess I need a vacuum diagram for this model.

Here are some pictures of the car.

Andrew-I passed on the green one I saw earlier when I found this for $200:dancefool

Army - Yes, both shafts turn.

Are you trying to re-live your china blue wagon!:P

That's a nice score for $200 the paint and body look great.

Wow. I guess so. I'll give you your $200 back when it's all fixed :D

Seriously, amazing score on that one.

100W light bulbs? I guess you're referring to grainy photographs - I do need to buy a decent camera but then I'd probably not want to use it in one hand whilst I fix the car with the other - I wouldn't want to drop a good camera!

Vacuum vacuum vacuum...

There's loads of information about the vacuum connections and transmission adjustments over on BenzWorld

DIY W123 Transmission Diagnose and Adjustment 722.xx OM 616-7 - Benzworld.org - Mercedes-Benz Discussion Forum

(Lots of the information from Govert too!)

But if you have a "bitsa" car (bits of this bits of that) I think you need to find out what sort of IP you have - there are probably 2 identification plates on it => one for the pump one for the governor. I guess the original pump would have been a MW/RSF pump - have a look through chapter 07-001 on the (NON TURBO now!) FSM

You then might be able to make head or tail of it all.

The 722.118 vacuum only transmission is a bit of a strange one from what I can make out. There is an earlier 722.118 that had the throttle linkage but not vacuum but MB didn't see fit to give the new 722.118 a different number or anything. Does your existing transmission have vacuum as well as a throttle linkage?

Anyway it sounds like you are planning on replacing it with your spare 722.118 - if you do then you can delete the botched throttle linkage to the transmission which should hopefully help. Don't chuck the old 722.1 transmission, however, as you might want to get some spare parts from it. The splined shafts for example tend to die in an abused 722.1 =>

http://www.peachparts.com/shopforum/diesel-discussion/299729-advice-reqd-shaft-spline-wear-measurements-possible-fix-722-118-transmission.html

Indeed - it deserves some BIG photos as far as I'm concerned

http://www.peachparts.com/shopforum/...s-dsc02500.jpg

http://www.peachparts.com/shopforum/...s-dsc02501.jpg

Army - The existing trans does not have any vacuum.

Andrew - I think I am. I miss that car!

Preemptive response to JimmyL (force of habit) - Hub caps are on the wall and will go on as soon as I find some wheels.

So, I fixed the throttle linkage and removed the the trans linkage (for lack of a better term).

I was looking at the main vacuum line and it's all screwed up too. I have the one that was in the 1980TD (replacement trans donor) so I think I'll swap that out too.

Thanks for the vacuum links! I'll have to read up and get it sorted out.

Army = 100W light bulbs....I heard they quit selling them in Europe. Some kind of crazy energy saving measure. Your photos are fine!

The VCV on the MRSF pump works together with a switchover valve. The switchover valve is responsible for the shiftback to first gear upon take-off.

Here is the vacuum scheme:

http://i185.photobucket.com/albums/x...cuumscheme.jpg

And here is how to hook up your VCV:

http://i185.photobucket.com/albums/x...h/MRSFpump.png

If you don't have a switchover valve, you can connect the transmission straight to the VCV.

On the side there is a vent line, connect a vacuum line to it and let it vent from the interior, stick the vacuum line into the interior.

The VCV can be adjusted: loosen the two bolts of the VCV, put the IP in full load with your hands, turn the VCV until you feel resistance, whilst keeping the pump in full load. Tighten bolts.