rough shifting
 

my 1980 300D is shifting very rough. i heard about changing something related to the vacum system but im not sure does anyone know what may be the problem? oil is clean. car has been sitting for a few years.

101 things it can be. Troubleshoot the vacuum system and then go from there.

http://dieselgiant.com/mercedesvacuumtroubleshooting.htm

the finger on the white valve on top of the valve cover is worn out is this the cause of bad shifting? i am very confused of this topic because of other listings. and does my 300D have a green dashpot vavle ? i cant find it.

the finger on the white valve on top of the valve cover is worn out is this the cause of bad shifting? i am very confused of this topic because of other listings. and does my 300D have a green dashpot vavle ? i cant find it.

does anyone know?

anybody?

Depends. Some models use it for EGR, trans, or both.

It can cause shifting problems even if its for the EGR. The vavle(s) can leak and cause a loss of vacuum to the transmission. you should check it for leaks.

vacuum issues
 

I had to play with my vacuum set up for two weeks before I got it to behave in a way I could be happy with!
Mines an SDL and has MANY things that need tweeked!
yours should be pretty simple comared to mine!
ther'es ALOT of articles pertaining to this problem ~~~just be diligent!