W123 driveshaft vibration
 

Hello everyone
1978 280ce
Had the flex discs and center support Bering and carrier replaced today at a shop
Told the mechanic about marking the driveshaft before taking it off and he said it won't matter so he did not mark it.
Also told him about lowering the car and rolling it back and forth before he tightened everything so everything gets seated but he didn't do it.
Can anyone guess what the result?
Yep I'm getting vibration between 40-50 mph
It's not horrible but I can feel it
Is there anything I can do to fix it ?

Updat:
The plastic centering bushing on front and rear of the driveshaft were broken
Didn't have them on me
Could it be that ?

Well you've got all of the answers in your first two posts - in a different era I'd suggest a horse whip and a beaten mechanic but these days that's frowned upon (apparently).

there are two ways.

The D shaft has a pointer and mate mark on the two halves - mate them together.

I have done a repair alongside a mechanic on a 202 chassis. We moved the shaft 1 tripod movement at a time. After a few tries the car went silent. This procedure is mentioned in the FSM - hence I suggest we do it.

moral.

dont stray from the FSM.

Thank you for ur response
Would you have the link for the fsm
Because I can't find it

From what I understand
Prior to July 1982 not all of them are marked:(

They are not all marked.

Several thread on the FSM such as this one

http://www.peachparts.com/shopforum/diesel-discussion/339083-123-manual-startek-sticky.html

Thank you for the link
But still can't find anything on correction the balance of the driveshaft

I've never seen anything specific about correcting an out of balance propshaft in the W123 FSM - perhaps Zulfiqar knows where to find it?

There are pictures in the W123 showing the marks that should be aligned but as you mentioned earlier pre-about 1981 propshafts weren't marked. In fact there's a note in the W123 FSM more or less saying "if you find that the marks aren't aligned please align them as we should have done this in the factory"...

The bit that I posted is in the 124/201 FSM and it was applied to a 202 car with a similar problem.

but the shafts are very similar, yes the pre 82 shafts have no marks which makes it a pain. another reason for such vibration can be an overtightened gland nut at the centre section (read that on a w124 german forum about half a year ago). It only gets to be slightly tight as it actually is a slip joint.

Another issue maybe worn U joint.

The tripod technique you mentiond
Did you do it with taking the whole driveshaft and rotated or just the back part from the center Bering back only?

firstly the marks were aligned and the carrier was inspected fresh grease slathered on the splines

we had vibration, after reclocking the rear tripod the car went smooth, at first we reclocked the front tripod with no result.

This was done at a mechanic shop with a lift - it would have become a horrific nightmare with jackstands only.

I had him replace the carrier Bering and center support
I'm gona go back to him and have re clock the rear part of the shaft
Thank a bunch for the input

propshafts...out of balance or out of phase?????????
 

Theres a feelin I get when I look to the west...

changing position and timing a driveshaft to improve indicates out of phase.

using clamps to add and move a controlled weight is balance or cancelling of an unwanted pulse.

they feel different to the driver, one feels like a cyclic push/pull. The other I can feel in the floor or the seat.

We used these factors to smooth out the hurky jerky and the throb at the truck shop

More importiantly, the splines in the center of the drive shaft need to be clocked properly.

At least on my 97 C280 , when the front tripod is in the up position, the rear should be facing down. It does not have a keyed spline so assembly can be random. You have 3 possible drive shaft positions to get the balance right. Then 3 on each end to get the trans / rear axle right.