Auto Shifting Problems

[paul_GB]

After a recent engine rebuild the auto box on my 230 was working sweetly (positive shifting at the right revs/load). During the latter stages of a recent long run it started to develop problems as follows :

1.  3rd to 4th change occurs at the correct revs but the transition is very slow (not a positive action)
2.  Pulling away in forward the gears only actually engage properly when I 'pip' the engine revs (and its clunky)
3.  Lower gear changes are now more clunky in general
4.  When pulling away in reverse the motion is now 'snatchy'

Good points :

1.  Kickdown works fine
2.  It stays in top gear once its there
3.  Changes happen at the correct revs

Ive checked and re-checked the oil level. Bolts all seem tight. Linkages all move ok.

Any thoughts..? Thanks..

[merrill]

Paul
see if this link helps

http://www.mercedesdismantlers.com/16BoltInstallationInstructions.html

They will answer questions via e mail if you need.
Regards
Matt

[paul_GB]

Thanks for the info Matt... very useful..

Cheers
Paul

[paul_GB]

.. after reading threads on this subject I am now suspicious that engine timing may be part (or all) of the problem. Ive seen Joe's comments suggesting timing can cause 'shifting' problems. I recently adjusted the cam sprocket timing (moved a link on the timing chain and installed a 4deg offset key). Hmm... could this be it or am I clutching at straws....? Thinking about it the transmission problems started about the same time. I need to undo the timing change and see if I get my slick gearbox back...

Paul

[ja17]

Hello Paul,

Since the automatic transmission is influenced from engine vacuum any change can cause shifting problems. Changes in ignition timing will cause a change in engine vacuum.