If those of you out there with manual (stick shift) transmission cars are anything like me, you will tend to remember who on the forum own manuals and some of the issues they have had with them. You may then remember that I have had a few issues with the clutch on my '90 190E-2.3 Sportline 5-speed. A pity really as I purchased this car due to its rarity and the fact it is a manual, and I really enjoy driving it. Apart from the clutch issues it has been reliable over the 3 plus years I have owned it.

For those who can't remember the issues I've had (and who have plenty of time to read and follow the story!) the threads (in order) are:
http://www.peachparts.com/shopforum/showthread.php?t=62898
http://www.peachparts.com/shopforum/showthread.php?t=68950
http://www.peachparts.com/shopforum/showthread.php?t=79274
http://www.peachparts.com/shopforum/showthread.php?t=79447
http://www.peachparts.com/shopforum/showthread.php?t=94692
http://www.peachparts.com/shopforum/showthread.php?t=106387
http://www.peachparts.com/shopforum/showthread.php?t=114385
http://www.peachparts.com/shopforum/showthread.php?t=147948

Anyway, to get back to the reason for this thread, I now have a new issue that has started over the last few days. The shift from 1st to 2nd has become difficult and to a lesser extent so has the shift from 2nd to 3rd. The problem is mainly difficulty getting it out of gear rather than into gear, although the shift into 2nd is a bit baulky on the move. At higher engine speeds the problem is most noticeable whereas shifting through the gears with the engine idling while stationary is not a problem at all. This tends to rule out the possibility of clutch drag (which I believe would make it difficult to get into gear whilst stationary). I should also mention that I replaced the clutch slave cylinder a few months back (something I don't think I mentioned in previous threads) at the same time I changed the gearbox fluid (and found the mystery part mentioned in the last thread above). Earlier threads mention that I have also replaced the clutch master cylinder.

My concern now is what may be causing the new problem, especially having found the mystery part whilst changing the gearbox fluid. On the weekend I will get underneath and check things like the shift linkage bushes and the gearbox fluid level. I don't believe the fluid level could be down much considering I only changed it a short time ago, however I know there is a slight gearbox fluid leak. To rule out the clutch hydraulics I will also bleed the system again.

I did a search but could not find anything quite like this. Any of you helpful folk want to offer suggestions?

Thanks,
Greg

__________________
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

In most cases this is a clutch release issue meaning hydraulics, but make SURE that you keep the trans full of lube. Poorly releasing clutches or poor driving style, moving the lever before the clutch is released, leads to worn brass which will cause shifting problems.

Good luck,

Greg:
I'm going to guess it's the synchro ring shared by first and second gear. If the 3 to 4 and 4 to 5 shifts are okay, then that gives more credibility to the bad synchro hypothesis. Plus that wire you fished out of the fluid (posted a while back) looked like part of a synchro assembly to me.
There are two main synchro ring assemblies in the trans. One is shared by gears 1 and 2, and the other is shared by gears 3 and 4. When shifting into and out of gears one or two, you are using that synchro to do it. If the assembly is screwed up, you may still be able to shift but it would be atypical, just as you describe. If so, then it's rebuild time.
Good luck.
Brian

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Brian
1995 E320 wagon

Greg:
Also, a synchro problem tends to show itself at higher engine RPM. The synchro's job is to try and get a fast spinning part (the engine) together with a slower spinning part (the gears in the gearbox). If the two spinning objects are nearly matched in rotational speed relative to eachother (low RPM or especially idle...no work to do there) then the synchro's job is easy. Large delta between rotational speeds means more work for the synchro, thus the problem you are experiencing.
Brian

__________________
Brian
1995 E320 wagon

Thanks Larry and Brian for your replies. They both sound plausible given the symptoms however I am now in a position to give you some more information as on the weekend I explored the problem further.

Selector linkage bushes all look and feel fine. Gearbox fluid level is full. I did notice that the gearbox input shaft seal must be leaking slightly though as there is evidence of transmission fluid (red) drips from the bell housing area. Previously drips from this area were clutch hydraulic fluid however the replacement slave cylinder has rectified that.

A test drive in a quiet area allowed me to investigate the problem further. I earlier stated that I believed it was not a clutch dragging (ie. disengagement/release) issue. Well I now believe it is. Strangely, it only occurs when the engine is at higher speeds. As I mentioned, gear selection is not a problem with the engine at idle. As the engine speed increases so does the difficultly in shifting gears. I have also determined that the problem occurs in any gear, not just 1st and 2nd. It is more noticeable in 1st and 2nd because these are the gears where higher engine speeds are used when accelerating from a standstill. If the car is driven to higher speeds then the same difficulty is experienced with selection of 3rd, 4th and 5th.

The problem, put simply, is that the clutch with not release with the engine spinning at higher speeds. If the engine is taken as high as say 4000 to 5000 RPM it is not possible to release the clutch to shift gears. If the car is allowed to slow such the that the engine speed decreases sufficiently then eventually the clutch will release. In fact, engine braking can still be achieved at higher engine speeds even though the clutch pedal is depressed!

Likewise, if the engine is revved above say 2000 to 3000 RPM in neutral, it is not possible to disengage the clutch to allow any gear to be selected until such time as the engine speed is allowed to drop back to idle speed. I appreciate this is not something someone would normally do, I simply use it as a means of demonstrating the problem. The clutch is behaving almost like a centrifugal clutch or the torque convertor on an automatic except for the fact that once released the clutch will remain that way.

I will next try bleeding the clutch hydraulics again to confirm that is not the cause, however I would have thought that a hydraulic issue would exist irrespective of engine speed. As I mentioned, with the engine idling gear selection is fine without any suggestion of baulkiness. Any clutch drag at idle would certainly show up with a crunch when selecting reverse however this is not the case. Rev the engine much above idle and selection of reverse is met with a crunch and selection of any other gear gets more difficult as the engine speed increases. The clutch pedal "feel" is perfectly normal.

Just something else that may be worth mentioning is that previously the clutch had a shudder problem that could only be avoided by getting the revs just right when moving off from a standstill. This problem was always worse when cold, when the car had sat unused for a few days, and in very humid or wet weather. The problem improved somewhat following replacement of the slave cylinder which I attributed possibly to the bell housing no longer being contaminated with hydraulic fluid. Since this latest problem suddenly appeared, the clutch shudder problem has completely disappeared.

The sudden apperance of one one problem and disappearance of another, and the engine speed sensitive nature of the problem makes me wonder if it is a mechanical issue with the clutch (rather than say a hydraulic one). For what it's worth I should also mention that being a 1990 model the car runs the "newer" version of the W124/201 gearbox and clutch with the dual mass flywheel.

Keep the helpful suggestions coming!

Thanks,
Greg

__________________
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

I am paying careful attention to the behaviour of the clutch and shift action at the moment (I need to as it really is not very easy to drive with this problem). Shifts (between any gear) below 2000 RPM are fine. From 2000 to 3000 RPM they are difficult. Above 3000 RPM, don't even bother trying! One thing I must comment on though, is that from a standstill the clutch is the smoothest it has been since I have owned the car. No shudder at all.

I also spent some time studying the WIS in the hope it offer some clues. I captured the most useful information in the attached screen shot.

Attached Thumbnails

 

__________________
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.