Read the post about snugging up the seat nets, so I did. Upon removing the seat back I discovered that the seat(back) lock appears to be part of the vacuum system. Owned this car for 5yrs and never knew that, always thought it would be mechanical. Both seat backs do not lock in place, thankfully I rarely have rear seat passengers and if I do they are always belted in . Where do I start my search for the diaphragm that operates this system

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85 300CD The FryrBird MY daily driver

I don't get what I'm looking at..? Is that the back, of the front seat..? My front seats used to lock, and needed the button depressed, in order to fold them foreward..All of a sudden one day, I stopped needing to depress the button, to fold them foreward...Is this the issue you are having, and talking about? I don't see it as a big deal at all though, and will likely, never fix it. I just thought of it as one of those useless little Mercedes options, they throw in, to fancy things up, or something.

Call Phil to see if he can get them. Otherwise you'll have to go to the dealer.

One consideration for having them lock as normal. In a crash your "body" weight will increase due to the added weight of the seat back folding forward and putting stress on the seatbelt system. Also you don't want the seat to fold forward and jamb, preventing you from getting out of the car.

Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

Yes that is a view of the inside of the passenger front seat,with one view kind of showing the vacuum line and the release button. I don't need to press the button to fold forward either, but with all the vacuum issues I've read about this could be something unique to CD owners as we have folding seats that seem to be vacuum controlled. Useless as long as you have nothing in the rear seat but anything else might hurt under severe deceleration (crash time) seat belt holding you back and seat back pushing you forward

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85 300CD The FryrBird MY daily driver

I did go to their web site but they have the normal door and others. Will try to give them a call this week.

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85 300CD The FryrBird MY daily driver

Crazy, absolutley Crazy, for Mercedes to even have made these locks, the door locks, and half of the rest of the features on these cars vac actuated. I don't see the point..They should have made the door locks electric, and the climate controls either mechanical, or electronic. I also think they should have just made things like these seat locks mechanical. What morons came up with these silly ideas, and designs? These little things are the ONLY features I don't like or agree with in the design of these great vehicles. They are the the flaw, in the design, in my opinion. Still better than the major flaws, in some of the other auto manufacturers designs. If this is the biggest flaw design, I guess I can live with it, and I don't seem to have very much of a choice.

Your car is now 26 years old and your complaining about a lock system that has lasted that long. The Germans don't do anything in a car if it does not have a purpose.
The amount of force you can get out a vacuum system is tremendous compared to what was necessary in an electric system 25 years ago ( 30-35 years ago when you think of design vs. production times.) Is it the perfect system, no, but it works well and is fairly cheap to fix. And it IS what is installed. Its different from what your used to in your trucking fleet. But with my 26 years of owning Mercedes I find it easy to work on and fix. And I have no desire to "reinvent the wheel".

Not pimping you, just pointing out that it really is a prety good system. Perfect? No Just whats installed.

Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

Wow, Dmorrison,
It sounds to me like you took my comments very personally...I'm sorry, if I have offended you, or your appreciation for the design. I personally, have never had any other problems with the vac. systems, aside from the seat lock. However, I see an aweful lot of guys having serious issues with them, and have been told by a lot of people about problems going back many years with the systems. I'm still learning about Mercedes, and their systems, and am becoming more familiar with them every day.
I'm an old Hot Rodder, Muscle Car guy. WHen working on say, a Chevy, or olds, the vac lines, and leaks, have always been the most sensitive, and the most troublesome systems. As a result, I developed, a huge distrust, and dislike, for anything Vacuum, aside from a power brake booster, or PCV. "The vacuum system, is the enemy", is how things became. As I said, I'm sorry if I offended you at all.

Hey CH,


I don't see "...the passenger front seat,with one view kind of showing the vacuum line and the release button. .." in any of your pictures. I don't see the release button.
I think it's probably a good idea for you to invest in the CD repair manual for your yr 300CD...and of course study everthing in it untilyou become a CD tech expert. And then you can help me fix mine if anything goes wrong....

My CD seats do stay in place. But I still do have some vac issues to correct as I only have the car for 1 week now.


AA

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'87 924S
'81 280SEL

Sold ->

81 300SD -
93 300E w/ 3.2
85 300D-
79 300SD
82 300CD
83 300CD - CA
87 190E 5 spd
87 Porsche 924S

"..I'll take a simple "C" to "G" and feel brand new about it..."

Pix three shows release button and vacuum hose about 1/2 way in the photo. Sorry I did not invert them to vertical. Remove your seatbacks and you'll get an idea of what we are looking at. I do plan on buying the cd for my CD, but thought I share this with all of us that have no pillars

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85 300CD The FryrBird MY daily driver

I have the same problem with my CD, I came across a post on this board when I did a search on another vacuum issue I was having. I always thought it was a mechanical issue, never would have thought it was related to vacuum.

I'll check the MB cds for more info on this and forward you what ever I can find.

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GC
1987 300E 104K
1984 300CD 112k R.I.P

No you did not offend me. It just that over the years on this forum I have seen posters that ***** about one system on another on the W123's. And rightfully so. It is old technology. Not perfect. But it is whats installed.
Many a person complains about a system, but the frustration is usually due to misinformation or lack of information about a system. I find this everywhere. Car, Aircraft ( MD80's) , computers ( I know I get frustrated with my computer and I know its because I am not a programmer ), It is human nature to be frustrated about something you don't fully understand that is perplexing you.
Your experience with your hot rods. I have rebuilt a 65 Mustang Fastback, completely. Did we keep it OEM, no. I also tried to improve some systems. Your hot rods, by definition, are not OEM rebuilds of the particular car you used. Otherwise it would not be a "hotrod". If I were rebuilding a Mercedes I would consider some modifications. But I am not interested in another 2.5 year rebuild project.
Mercedes uses vacuum throughout the car. EGR control, transmission shifting, engine shutoff, door locks, AC flap controls and fuel control. So to eliminate the vacuum controls would be very complicated and encompassing.
With that in mind, My experience has led me to believe that it is easier to just maintain the system as designed by Mercedes. The items in my sons 65 Mustang that we "modified" ( T-5 tranny, higher performance engine, suspension modification ) are those items that we have to continuously go back and "fix" compared to the rest of the OEM car system.
On the other hand, my daughters 83 240D is kept OEM and requires very little work.

Again no offense. I have just found over the 26 years of working on Mercedes that maintaining a car that is a daily driver is easiest if you keep it stock. Just my observation.

If anyone want to eliminate various parts of any particular system on the car, at least document it on the forum so that it can help others.


Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

If it weren't vacuum issues you'd be hunting down electical issues. Pick your poison I guess.

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1980 300TD-China Blue/Blue MBTex-2nd Owner, 107K (Alt Blau) OBK #15
'06 Chevy Tahoe Z71 (for the wife & 4 kids, current mule) '03 Honda Odyssey (son #1's ride, reluctantly) '99 GMC Suburban (255K+ miles, semi-retired mule) 21' SeaRay Seville (summer escape pod)

I have a CD too and I just looked in the manual and found that if doors are open, then the seats fold down without having to press the button. Only requires button press when doors are closed... So yours may be functioning properly without you even knowing it! Now, why would you want to fold the seat forward while the doors are closed, not the slightest idea!

Also, I think the diaphram is attached to the bottom of the seat. White box near the vacuum Y connector.

Doors open, closed, engine running, engine stopped, 0mph and above the seats move Thanks for the tip on where to look. I'm thinking it has to have some sort of interlock device with ignition-engine-motion. Not just for keeping the kids in the back at the Drive-in. Oops showing my age

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85 300CD The FryrBird MY daily driver