W108 leaking automatic transmission fluid from the speedometer linkage

[zdzich]

Hello,
Can anyone tell me how the speedometer output is sealed ? Is there an O-ring or something else ? i re-installed the transmission and the engine and I see there is some transmission fluid coming out of the hole where the speedometer linkage is connected. Transmission type is GA 230 SL E. Thank you.

[mbzse]

Zdzich,
Yes there is a little lip seal for the speedometer cable attachment. Among other postings you may find with the "search" function, our very own M-B Doctor (DanC) as well as George Davis have written these useful guidelines:
http://www.sl113.org/forums/index.php?topic=6182.msg38737;topicseen#msg38737
/Hans in Sweden
.

[zdzich]

Thank you Hans, I very appreciate your help. To bad that I didn't do it when I had the transmission out of the car. It would be very easy but I didn't expect that it will leak. Regards,
Richard

[zdzich]

Hans, I just removed the speedometer gear and it is different than the one described by M-B Doctor (DanC) and George Davis. I took some pictures. Maybe in later models like the one described by M-B Doctor (DanC) and George Davis Mercedes made changes.

[mbzse]

.../... removed the speedometer gear and it is different than the one described.../...

You have taken good pictures of the parts. You are right, the automatic gear boxes have a different design for the speedo cable attachment compared to the manual gear boxes. I was not aware that difference was so significant.  I do own one automatic but I have not worked on it, in this area... Great with this Forum, you may learn.
So, others can contribute with info on the auto speedo cable attachment R&R
/Hans in Sweden

PS   I attach a picture (borrowed off the Web) showing cable attachment point left side of gear box  DS
.

[zdzich]

Thank you Hans. I found that the sleeve in which the speedometer gear shaft is rotating is worn out. Now I have to find a new one or take this one to a machine shop and get it repaired.

[zdzich]

New sleeve and O ring installed and the problem is solved.

[wwheeler]

Thanks for posting the pictures! My 280SE also has a slight leak but only after the engine hasn't run in a while. I guess the trans fluid is running down and overfilling the pan. Yet another problem to fix.

Looks like the sleeve was cracked and that is where the oil leaked out? 

[zdzich]

No, the crack is after the O ring seal. It was worn out sleeve and old O ring. So, friend of mine who has a small machine shop made me a new sleeve and I replaced the gear and O ring. Actually, the whole part with new gear and O ring is still available from any Mercedes dealer but is not cheap. I paid for the new gear about $30. The housing was much mo9re expensive, I think around $200. But since my friend was able to install me a new sleeve I didn't have to spend that much money.

[wwheeler]

Zdzich,

How did you get the speedometer gear and housing out? My speedo cable is out, but the housing won't move. Do you have to remove the small cover that is just behind the housing? I am trying to replace the O-ring seal.

Thanks,

Wallace 

[ja17]

Hello Wallace,
Yes remove the rear cover. It pins the housing in place.

[wwheeler]

Ok thanks Joe. I see the hole in the housing above. I also went out and noticed a bump on the cover that seems to align with that hole.

I am going to try my best to make it to the PUB this year for the first time!

Wallace

[wwheeler]

Speedo housing came out when the rear cover was removed!

One thing I did notice. The new #113...speedo cable from the classic center for the W111 had a small rubber sleeve on the end that went into the housing on the trans. The old one did not and any aftermarket pieces I have seen also did not have this seal. Maybe why some speedo cables weep a bit?