1974 240d 4 speed transmission, help please. - PeachParts Mercedes-Benz Forum

mattbone · #1 11-29-2010, 05:40 PM

I've posted before with issues, but I fixed the obvious problem to no avail. I had thought the master or slave cylinder went out while I was driving, but the bracket that holds the clutch pedal to the master cylinder had cracked. I got that TIG welded back together and bled the system. Now when I push the clutch pedal it doesn't give at all. I may not have bled the system correctly, but I would think it would feel differently even if it just needed bled. It looks like some fluid may be leaking from the edges of the slave cylinder on the transmission. Also, I think the master cylinder could have been damaged when the pedal cracked. I think I put a small crimp in the line that goes from the master cylinder to the brake fluid reservoir while removing the clutch pedal bracket that could be causing issues as well. I was just wondering what all I should do before I order a new slave and master cylinder? Also, what kind of line should I get to replace the line that goes from the brake fluid reservoir to the master cylinder? Thanks for your help.

t walgamuth · #2 11-29-2010, 09:22 PM

Sounds like the crimp has the flow blocked. It should be a standard metric brake line which you can buy at autozoo.

Buy about 2' extra and make a large 3" d loop near the slave cyl to take the movement of the engine and tranny.

mattbone · #3 11-29-2010, 11:51 PM

Ok. thanks. I'm going to try and get it fixed and see how long I can drive this car. It seems to smoke a lot and have some blow by. It also leaks a little oil and when it first starts up idles a little rough, but it starts every time and drives fine, so I will drive it and hope for the best.

t walgamuth · #4 11-30-2010, 06:06 AM

Does it have the pencil type glow plugs? Is it hard to start? Rough idle on start up often indicates a glow plug problem. It will smoke blue too from unpburned fuel.

mattbone · #5 11-30-2010, 11:00 AM

The person I bought if from said they replaced the glow plugs with new ones that go in a later model diesel.

mattbone · #6 12-01-2010, 06:49 PM

It had been a while since I looked at my car, but the clutch pushes down about halfway with almost no resistance and then about halfway down it gets hard and wont go all the way to the floor.

t walgamuth · #7 12-01-2010, 07:01 PM

Quote:

Originally Posted by mattbone

The person I bought if from said they replaced the glow plugs with new ones that go in a later model diesel.

I would suspect the glows on the rough idle at start and bluish smoke til it warms up and smoothes out.

Daman858 · #8 12-02-2010, 05:56 PM

Look at your glow plugs...if they are connected by regular auto type wire and don't have white ceramic insulators on them, they are the newer pencil type. The kink in your clutch line is probably the culprit. You might want to pull the injectors and put some ATF down the holes to get your rings back into shape and clean your injectors or maybe even rebuild them Not too difficult a job. I have stopped oil leaks by just tightening up things underneath like the oil pan bolts and the oil filter housing bolts. Good luck!

mattbone · #9 12-02-2010, 06:27 PM

Ok, I just started her up for the first time in a couple weeks and pushed on the clutch. I heard a kind of grinding noise when I tried to push it down. Like I said previously, it goes halfway to the floor with almost no pressure then stops, pushing it past the point it stops makes a grind noise, not verry loud though. It doesn't go down much either. Just makes noise. Is it possible the clutch is stuck and wont release? I've driven it shifting with out the clutch since its been acting up. Also, I dont see the kink that was in the line anymore. It wasn't a complete blockage in the first place, just a half crimp almost. It is a plastic almost rubber line.

Althogh the transmission seems worse than expected the engine runs better than I remembered once it warms up I guess. It idles rough, then it smoothes out pretty even. which could be the glow plugs like stated, bu tI'm not too worried about the engine at the moment. I just want to get it driveable again.

mattbone · #10 12-02-2010, 06:34 PM

"I have had two such failures. The first was on my 1975 240D. I was in Alaska in 1976-1978, and while there I found Mobil 1 synthetic oil. It was like water pouring out of the can, but that stuff made cold starts no problem. But it would leak a little past the rear crank seal and get on the clutch, and when that happened the clutch would chatter in a standing start horrendously. Well, seems I damaged on of the little coil springs that are arranged circumferentially in the clutch disc, making it bulge out on one side. After about 130,000 more miles, I stepped on the clutch one day and it popped, and the pedal went to the floor and kind of stayed there, limp. That turned out to cost me a clutch job. The little spring was machined into two smaller springs, which is what made the clutch inoperable."

I just read this on another forum and it sounds like what is going on with my car. I noticed oil leaking from what looked like the transmission. It was either leaking from the main seal or from some part of the engine and dripping down to the transmission.

t walgamuth · #11 12-02-2010, 07:06 PM

You probably did nothing to the little spring. That is one way that clutch discs fail.

t walgamuth · #12 12-02-2010, 07:07 PM

Quote:

Originally Posted by mattbone

Ok, I just started her up for the first time in a couple weeks and pushed on the clutch. I heard a kind of grinding noise when I tried to push it down. Like I said previously, it goes halfway to the floor with almost no pressure then stops, pushing it past the point it stops makes a grind noise, not verry loud though. It doesn't go down much either. Just makes noise. Is it possible the clutch is stuck and wont release? I've driven it shifting with out the clutch since its been acting up. Also, I dont see the kink that was in the line anymore. It wasn't a complete blockage in the first place, just a half crimp almost. It is a plastic almost rubber line.

Althogh the transmission seems worse than expected the engine runs better than I remembered once it warms up I guess. It idles rough, then it smoothes out pretty even. which could be the glow plugs like stated, bu tI'm not too worried about the engine at the moment. I just want to get it driveable again.

I'd take that line and get any hint of a kink worked out of it and try to reconnect it in the new configuration.

mattbone · #13 12-02-2010, 07:09 PM

I'm going to try and get a friend over and do anything I can to fix the problem tomorrow if all goes well. If I can't fix it I want to at least be able to narrow it down to the master/slave cylinder, or the clutch.

mattbone · #14 12-09-2010, 04:37 PM

Can you gravity bleed your slave and master cylinders?

mattbone · #15 12-09-2010, 05:16 PM

So I just started to bleed my slave cylinder from the cylinder out instead of from the cylinder up and nothing but oil came out... More than likely im SOL?