240D no clutch pedal no gear engagement - PeachParts Mercedes-Benz Forum

ichbineinekrous · #1 01-14-2008, 01:14 PM

So I've been reading all the posts pertaining to my problem. i.e. back bleeding the clutch slave cylinder by joining its bleeder bolt to the right front brake caliper. My question is this. The reservoir above the brake MC is completely full. Is it still probable that my problem is air in the slave cylinder? This car was converted from auto to 4-speed manual by the PO and having only had it for 4 months I've never had the opportunity to even look at how it was done. It always worked and I had my hands full with everything else on the car that was sub-par.

I believe I've seen the receipt for the new clutch pressure plate which the PO said he put in at the same time as the tranny. Thanks for listening

t walgamuth · #2 01-14-2008, 01:19 PM

I cannot understand your situation, what is the problem?

Tom W

kerry · #3 01-14-2008, 02:08 PM

Are you sure the back reservoir of the MC is full? I believe the back reservoir feeds the clutch and a low reservoir causes the clutch to fail before the brakes.

winmutt · #4 01-14-2008, 02:26 PM

His brake indicator would be on if this was the case. If bleeding doesnt fix the problem then the slave/master needs to be replaced, I would go with the cheapest one. This same problem was my excuse for picking up a flywheel, pedal ass., trans and shifter this weekend for $90.

t walgamuth · #5 01-14-2008, 03:14 PM

I am not sure the indicator will activate before the level goes below the clutch feed nipple. (no kidding on the name).

Tom Walgamuth

pawoSD · #6 01-14-2008, 03:59 PM

Quote:

Originally Posted by t walgamuth

I am not sure the indicator will activate before the level goes below the clutch feed nipple. (no kidding on the name).

Tom Walgamuth

Isn't that nipple on the bottom of the reservoir? I am pretty sure it is....thus the light would be on if it was that low.

ichbineinekrous · #7 01-14-2008, 04:08 PM

the problem is that when the clutch pedal is depressed, there is no resistance, and thus no disengagement from the flywheel. It won't go into gear. I'm pretty sure the slave cylinder is shot. I'm also trying to diagnose this remotely, its my GF's mercedes and she may or may not be able to tell if the MC reservoir is full. Much less find the clutch slave cyl and see if its leaking.
I just had her take to a local (for her) indy and so we shall see what he says. Thanks for the quick input.

Cervan · #8 01-14-2008, 04:14 PM

Quote:

Originally Posted by ichbineinekrous

the problem is that when the clutch pedal is depressed, there is no resistance, and thus no disengagement from the flywheel. It won't go into gear. I'm pretty sure the slave cylinder is shot. I'm also trying to diagnose this remotely, its my GF's mercedes and she may or may not be able to tell if the MC reservoir is full. Much less find the clutch slave cyl and see if its leaking.
I just had her take to a local (for her) indy and so we shall see what he says. Thanks for the quick input.

Remember, on these cars you have to reverse flush the clutch system thats how you get the air out. I just replaced my slave cylinder on my 81 240d, and i will tell you right now that is NOT a job you want to do.

kerry · #9 01-14-2008, 04:15 PM

Quote:

Originally Posted by pawoSD

Isn't that nipple on the bottom of the reservoir? I am pretty sure it is....thus the light would be on if it was that low.

No, the nipple is deliberately not at the bottom, so that the clutch will fail before the brakes will.

t walgamuth · #10 01-14-2008, 06:01 PM

Quote:

Originally Posted by kerry

No, the nipple is deliberately not at the bottom, so that the clutch will fail before the brakes will.

correct.

Tom W

Stevo · #11 01-14-2008, 06:15 PM

First check the clutch master cyl by pulling the carpet down in back of the pedals and feel or look for the steel line running down from the master cyl. Is it wet, brake fluid under the carpet, No? good. That job isn't as easy as the slave.

I dont think your brake warning light will tell you if the brake fluid is empty in the aft chamber, look close.

matthias08 · #12 01-14-2008, 07:39 PM

right before i got my 240 from a friend of the family... it had the same problem && i got a new slave cylinder out of the deal too.

Scott98 · #13 01-14-2008, 08:07 PM

Quote:

Originally Posted by Cervan

I just replaced my slave cylinder on my 81 240d, and i will tell you right now that is NOT a job you want to do.

Why? Its not hard to access and there are only two bolts holding it in.

Scott

Scott98 · #14 01-14-2008, 08:08 PM

Why do they have to be reverse bled? Can't you use a pressure brake bleeder? Can't you bleed it like brakes? That's how I did mine this weekend. You're just forcing fluid from the brake resevoir, through the lines and into the slave.

Scott

pawoSD · #15 01-14-2008, 08:25 PM

Quote:

Originally Posted by kerry

No, the nipple is deliberately not at the bottom, so that the clutch will fail before the brakes will.

I didn't mean the very bottom, but toward the bottom, likely low enough that the float switch would trip if it was at the level of the nipple.

Even if it was at the bottom of the reservoir there'd likely still be enough fluid in the M/C to properly operate the brakes.