my 240d's clutch will not engage!
 

i just finished putting a new engine in, and went to take the car out for a test drive. much to my surprise, the clutch will not engage fully! the hydraulics are bled and have plenty of 'spring' in the pedal, that does not seem to be the issue. in 1st gear, on flat ground, the car will not do more than slowly move forward (5mph or so) no matter what rpm. the car can sit stopped in 1st gear with the clutch pedal fully released and there is barely a change in RPMs.

what could this mean? is it some odd kind of failure? did i do something wrong when assembling it?

if nothing else can someone post the exploded diagram of the 240d clutch / flywheel / bearings ?

Have you checked your clutch fork for proper movement?
It almost sounds like a loose or bad clutch cover.

when i had it apart, i checked everything as best as i could figure out. clutch slave cylinder functioning properly, throwout bearing smooth, fork moving properly, pressure plate bolts replaced, clutch disc had plenty of material left.

the only thing i can come up with is either i lined something up wrong, or assembled something out of order.

assembled in this order:

flywheel -> clutch disc -> pressure plate -> throwout bearing -> clutch fork -> clutch slave.

lined up the throwout bearing to where it fit into the clutch fork properly. installed the clutch fork onto its pivot rod and the clutch slave cylinder piston.

my theory is something in the assembly is wrong, causing the clutch to be disengaged even when the slave is not pushing. i just don't know what that could be, and i hate to pull teh driveshaft and transmission back out without any idea what i'm looking for. as i said, if someone could at least help me with the exploded diagram that would be helpful.

Is it possible to put the new clutch in backwards ?
Did you take pics as you put it back together ?
That might show what happened...
Did you use one of those alignment tools ?
Did you change the pilot bearing ?

https://lh5.googleusercontent.com/_K...325_154102.jpg

only picture i had. the clutch disc only fit properly one way. the other way wouldnt lay flat onto the flywheel for me to put the pressure plate on.....

-picture above.
-aligned using sockets in there, it fit together fine and the splines on the tranny input shaft fit in properly.
-used the same bearing, it seemed to be in fine working order.

Good, or bad depending on how you look at it... I have seen tractors which the clutch could be reversed... did not know about an MB.. sounds like it ought to work...

OK, one last shot..

have you seen the instructions as to measuring the amount of wear on a clutch ?
the " Go NO Go " fork tool ?

Are there ANY mechanical linkages involved in moving the clutch .. or something which could be not allowing free movement ?

Is the movement towards the rear of the car by the clutch pedal full ?

the metric i've seen was 1/16" or more from material surface to the top of the rivets. it had more than that.

what would be the symptom of the clutch disc having been installed backwards?

take the slave off and see if the arm springs back at you, if it does you might not have to take the trans back out. Stop running the engine you are ruining the clutch, plan on removing the trans and figuring out what you put in backwords.

I was not suggesting you did not have enough material on the clutch...only that the way in which that measurement is taken from outside the trans might be useful in seeing if the position of the clutch is correct....
Symptom of clutch backwards ? Non proper functioning ...LOL
I did not assemble it backwards... due to reading the instructions closely.. but was impressed with how much work I would have had to do had I had to take the whole thing back apart ....

right but would a backwards clutch fail to engage or fail to disengage? that is the big question in my mind. i can't find any good pictures or explanations on any existing threads / guides.

I do not know the answer to that...
Did you attempt to install it both directions and it fit one way and not the other?
Did you take pics of the old one coming out ?

i did attempt both because i wasn't sure and couldn't find an answer. it seemed that it only fit one way. the way i put it in, the disc would fit flat against the flywheel just by hand. the other way, the disc would not lay flat onto the flywheel (although i did not try to force it).

and no, i stupidly did not take pictures when i pulled it apart. :rolleyes:

LOL, you were probably low on electrons in your camera anyway....
How about the physical mechanical connection where the slave works...
any binding there ?
You have to go back and check everything... you can not assume because you have checked something already that it is off the list of potential problems... not fun... but can save you time in the long run... I have had things like this where I had to close the garage door and come back a week later.... and sometimes sleeping on a problem does help.... confirmed by scientists and talking about on Charlie Rose a lot lately...

What's this ring on the clutch fingers?
https://img.skitch.com/20110331-nj92...hgpbt9wbk9.jpg

not as far as i can tell. the clutch sorta functions in a sense - if the pedal is released it does not engage, but it seems to be almost barely touching because the car will roll slowly forward with the brakes off in 1st but couldn't go up my driveway. if i push the pedal in, it has a normal clutch pedal feel, the lines are bled fully, and the clutch becomes absolutely 100% disengaged (i.e. no movement whatsoever).

part of the assembly? it was there when everything came apart, it seems to be the bit that the throwout bearing fits up against.

Does the end of the rod on the slave cylinder have any adjustment available ?

That should not be there. The t/o bearing rides directly on the clutch fingers. It looks like the clutch is partially engaged because of it.
Mine did not have any ring.

then why was it there from the factory?

Did you have any prankster helpers present as you took it apart ? LOL

I don't know if that's the way it came from the factory. I have a clutch assembly in my 300D that I pulled off a 240D and it did not have that ring.

Can you post that picture Larger perhaps ?
and possibly Lighter ? I am assuming by the arrow you already have it in something like photoshop ....

well can anyone tell me whether the clutch disc should lay flat on the flywheel before the pressure plate is installed? and where can i get an exploded diagram of the clutch assembly?

I can not imagine that an exploded view is not posted somewhere in the archives ....
Ok.. good .. now lighter and more closeup ? LOL

As you buttoned it all up... you had no problems with some bolts being tighter than others ?
Did you use a torque wrench ?

I think the Haynes manual has one. Another place is online at detali.ru. You might be able to find an exploded parts view.

http://www.auto-parts.spb.ru/cat/cat...d4e9fee4e79aac

No ring in the diagram like in your photo.

Could that ' ring' be the other side of the T/O bearing assembly ?

http://i55.tinypic.com/j8l2qs.png

this diagram doesnt show much but from what i can see i assembled everything properly.

the diagram doesnt show enough to show the ring there. i know for a fact it was there already, so my only guess is that its part of the throwout bearing somehow? i dunno.

but arent all parts of the throwout bearing assembly aft of the pressure plate? i guess i could see a part being stuck to the fingers, but that still wouldnt explain why the clutch wont engage....would it?

http://i55.tinypic.com/2qbwtig.png

based on this photo, i think that ring is just the front part of the throwout bearing (actually i guess its supposed to be called the release bearing?). i'm assuming it just was stuck and never came off, and that still doesnt explain why the thing isnt engaging

I am out for the night... will try to get my manuals out tomorrow if you are still needing the diagrams...
In post 29 I proposed that...
later,Greg

Yes, all parts of the t/o bearing are aft of the pressure plate. It would be like you have an extra thick t/o bearing. It could cause your clutch to be partially engaged at all times.
It's just that I've never seen something like that ring on any clutch, not just on a Mercedes.

well assuming its just part of the bearing that stayed stuck to the fingers, it should still fit back together the same, right?

i guess i'm just going to have to pull the damn transmission out and fiddle with everything a bit. UGH right after i finished messing with the driveshaft i have to pull it back out again.:mad:

Compared to many things, pulling the transmission on a 240D is fairly easy, plus it's light enough that you don't need a transmission jack.
You don't really need to pull the driveshaft out. Just loosen the big nut on it and you can push it back far enough to for the transmission to clear it once you disconnect it from the flex disc.

In the 240d there is enough room in the engine bay for a tea party for 4. I can drop the trans in a 240d in under an hour. Not so much on the 617 or 603.

Yeah yeah I know but I've been under the car all day for several days so I'm still not excited.


In class now, going to drop the transmission when I get home

Maybe Iam not looking at this right, but that ring to me looks like one side of the throw out bearing. Iam thinking it is turned around. that ring should be the side towards the pressure plate fingers?

the left picture shows the fingers the ring side of the T/O bearing rides against when the clutch peddle is depressed..

http://img.eautopartscatalog.com/liv...1610784SAC.JPG

The left picture is the side that is to face the pressure plate

http://img.eautopartscatalog.com/liv...1606273SAC.JPG
Charlie

Well you usually find an automatic behind those engines.;)

So from charlie's post I know I put the clutch disc in correctly. Ill take pictures this time and see what you all think before I try reassembling.

Back to work now!

here's the clutch slave. does anything look wrong?

https://lh3.googleusercontent.com/_K...331_133622.jpg

http://lh6.googleusercontent.com/_Kw...331_133605.jpg

I don`t think that rubber gasket is suppose to be sticking out like that. and as wet as it is, looks like it is leaking. it should be dry. I don`t remember if you said you replace this or not. lookes like maybe you have an old one?

Charlie

well i guess the thing to do is to go try starting it in 1st gear to see if the clutch is engaging when the slave cylinder is out :eek:

or maybe put it in 1st and see if i can push it backwards right now?

edit: facepalm. i already have the shift linkages and driveshaft detached from the tranny. i guess ill go throw it in gear and see whether i can turn it by hand with the flex disc and then decide whether to try mounting everything back up for further testing. sound good?

ok so with the transmission in gear, i can turn the output shaft via the flex disc with my hand. its really tough, but with a rag wrapped over the flex disc i can slowly turn it like 1/8th of a turn at a time. the engine is not rotating with it, but i'm wondering if that is normal or not.

i'm assuming it should be impossible for me to do that if the clutch is properly engaged.

just to recap, this was done with the slave cylinder totally removed. if my assumptions are correct, the issue is now narrowed down to the bearing, the clutch disc, or the pressure plate.

and to answer that last question, yes this is the old slave cylinder. pictures of new ones don't look like that so i agree it should probably be replaced now, but see my previous post about what its doing with the slave removed.

anyone?

You should not be able to turn the output shaft without turning the engine while the clutch is engaged and the transmission is in gear.

^X2. There is no way you should be able to turn the output shaft with the transmission in gear with a properly operating clutch.

clutch problem?
 

you can put the disc in the wrong way spring side to presure plate smooth disc side to the presure plate flywheel. pull transmission and check.