1985 300D turbo drive shaft installation problem - PeachParts Mercedes-Benz Forum

Jim Beville · #1 06-01-2007, 06:31 AM

I just finished re-installing my driveshaft with new flex discs ,center support and bearing. I marked the drive shaft before disassembly to insure that it was reassembled correctly. I think it may be one spline off as it seems to have some balance related vibration at speed that did not exist before I messed with it. I remember one of the posts saying that the '85 and newer models have alignment marks on the driveshaft halves somewhere, although I did not see any . Any suggestions on what I may have done or a resolution to the new vibration problem are apprieciated.Thanks ,Jim Beville

rs899 · #2 06-01-2007, 07:27 AM

They do have marks, but they are not easily recognized. The best way I can describe it is they seem to be cast into the metal- I think there is a photo of it in the Factory manual. It's one of those things that once you see it, you've got it. But it is fairly subtle. I hope someone else can do a better job of helping here or provide a photo.

Rick

tobybul · #3 06-01-2007, 08:37 AM

Quote:

Originally Posted by Jim Beville

I just finished re-installing my driveshaft with new flex discs ,center support and bearing. I marked the drive shaft before disassembly to insure that it was reassembled correctly. I think it may be one spline off as it seems to have some balance related vibration at speed that did not exist before I messed with it. I remember one of the posts saying that the '85 and newer models have alignment marks on the driveshaft halves somewhere, although I did not see any . Any suggestions on what I may have done or a resolution to the new vibration problem are apprieciated.Thanks ,Jim Beville

Is it just the 85 and newer models that have the marks? Could the 84's have it too?

rs899 · #4 06-01-2007, 10:15 AM

If I recall correctly ( and this IS in the FSM) all cars from sept 82 had the marks. Again IIRC. IIRC.

Jim Beville · #5 06-01-2007, 01:24 PM

Are the alignment marks on the tubular section of the drive shaft or the machined /splined coupling? Do the driveshaft ends have to be returned to the original position/ relationship with the trans and differential( does not seem like that would matter, but, I'd rather ask than miss something)? Any pics would be greatly apprieciated. Thanks ,Jim

barry123400 · #6 06-01-2007, 02:25 PM

This does not sound too cool. I wonder if one of the flex couplings is out of balance? It should be a standard quality control thing to balance check them in manufacturing.
You have to go back and line up the driveshafts exactly on the same splines before even looking there. One spline out does not sound like much but I just do not know. Also have a look to see you did not accidently knock off a factory shaft balance weight.

winmutt · #7 06-01-2007, 02:28 PM

Funny I have reassembled mine with different shaft parts from different cars and have zero vibration.

ytr1903 · #8 06-01-2007, 02:31 PM

I just did the same job that you are describing. It was on a 190D. The marks are on the tubular sections of the driveshaft. On one section is a straight hash mark and on the other section are two diagonal lines in the shape of an open-ended arrow. The idea is to line the sections up so that the straight line is lined up with the pointed open end of the arrow. This may sound more complicated than it really is. They are not real easy to see.

Tom