1987 560sl vacuum question - PeachParts Mercedes-Benz Forum

ddayme · #1 12-09-2009, 01:34 PM

Hi!, on my 1987 560sl, I've been doing some climate control repairs, and noticed that the fresh air vents don't work. I found a red/blue vacuum line going from the passenger side vacuum pots that is not connected to anything. Also, on the back of the fresh air/recirc. switch, there is a vacuum line going to the back side of it, into a rubber connecter that has 3 holes, and only a solid red vavuum line going to it. Are there any other vacuum lines that are supposed to go there as well? One thing I can't seem to find is a good picture/diagram of the vacuum system. If I had a diagram/picture, I'm pretty sure I could figure it out!

I'm sure someone has dealt with this in some form or another, and any help would be appreciated!

Thanks,

-DDaymen (1987 560sl, 195,000 miles)

meltedpanda · #2 12-10-2009, 05:50 PM

see if this helps
http://www.peachparts.com/shopforum/attachments/mercedes-benz-sl-discussion-forum/72341d1253029823-c-control-107-flaps.jpg

ddayme · #3 12-10-2009, 05:54 PM

Yes, that definatly helps, I think I' missing vacuum that would be the source for all the climate control vacuum!

ddayme · #4 12-10-2009, 05:57 PM

But I don't see the recircu. air switch, which has one red vacuum line going in, but no others going out. Also there is a red/blue vavuum lind going to the right side (passenger) vacuum pots for the fresh air vent that is dis-connected>

ddayme · #5 12-10-2009, 06:01 PM

Never mind, now I see it on the diagram, now I just need to find the source for all the climate control, from engine compartment?

ddayme · #6 12-10-2009, 06:21 PM

Okay, I found the source, have good vacuum, now it seems that the little manifold that directs vacuum to the various pots does not function. The plug going in to it has current on all but 1 point, and it also appears that someone has had it out/worked on it, as it has electrical tape holding it together, it has that "been taken apart" look, I'll do the same and look for bad elec. connections, and also apply external vacuum to it, work the switches and see if it directs vacuum. Anybody have a diagram of switch position/vacuum manifold relationship?

meltedpanda · #7 12-10-2009, 06:53 PM

not sure I understand what you are looking for , the electrical connection?

ddayme · #8 12-10-2009, 08:51 PM

What I was looking for and found, was the vacuum line going in to the vacuum manifold that is behind the glove box. I the noticed that the manifold, if that is the right term, had been removed once or more and been taped back together. I removed and marked the 5 vacuum lines on it, took out the manifold, and removed the cover. Some of the solder connections looked suspect so I re-soldered them, not I want to make sure the solenoids contained therein are functioning. what I really need is some sort of diagram that shows what port on the manifold corresponds to what climate control switch/button. The elec. plug to this manifold has power to it, so all I need to do is make sure vacuum is getting where it needs to go per climate control button position or rather buttons "pushed in", like defrost, etc.
Hope that clarifies what I'm doing!

meltedpanda · #9 12-10-2009, 09:13 PM

that is the quadruple valve. is the part number 1078002278, there is a good picture of it on the EPC website, are you a member ? if not, it is simple and is free ( you have to give a credit card to prove you are in US) I would send you the picture but I can't figure out how to save it to a file.

meltedpanda · #10 12-10-2009, 09:26 PM

I can email it to you if you send me your email by PM

ddayme · #11 12-10-2009, 10:41 PM

Well, it seems that the vacuum lines coming out of the little manifold were not in the correct order! and according to the diagrams I have found, the numbers the diagrams show on the little manifold and the corresponding vacuum lines not coincide with what it should be. I went by the actual drawing, not numbers/vacuum line relationship. also, the diagrams are kind of confusing, as they show that the vacuum ports labeled, from the source vacuum to the right or to the other side of the manifold, as 2,1,3,4. On the actual manifold the order, from source to right as 4,3,1,2.It show the line going to the fresh air/recirc button as coming from the port labeled #4, when on the actual ,manifold in the car it comes from #2, etc.! either that or my 1987 560sl is some kind of really ass-backward! However, attaching all the vacuum lines according to where they go looking at the picture, not using the numbers, everything works as it should, like the fresh air only working in a/c mode, etc. once I am finished, I will make a diagram/pictures and post it.

Like I said, maybe my car is all backwards, or the diagrams from the repair CD are screwy, I will find out once everything is back together!
Also, the labeling on the diagrams, I can't really tell what color combos. the lines are, maybe labeled/abbreviated in german? anybody else found ot this to be true?

Thanks,
-DDaymen

ddayme · #12 12-11-2009, 10:21 PM

I got the vacuum diagrams you e-mailed me, I was able to save both of them to my computer. I will finish putting everything back togther on sunday, and I also found that the center vent vacuum pot is bad, nothing happens when vacuum is applied. Hopefully I can remove it for repair without removing the dashboard!

Thanks again for the diagrams!

-DDaymen

meltedpanda · #13 12-11-2009, 10:30 PM

great , let me know

ddayme · #14 12-14-2009, 10:36 PM

Everything is back together, the center vent flap had been blocked open, I re-connected the lift arm,ut it don't work! always blows to defrost, economy gauge works, I was told this shares vacuum with the center vent source, I have many many threads about how to check why center vent inoperative, but so many theories I'm a little confused! Isn't the vacuum pot for the center vent the oneto theleft of the radio opening? when vacuum is applied with a hand held vacuum pump, to either ports on the pot (or actuator...don't remember where I got vacuum pot from), either both at the same time or one or the other with one blocked off, no action, won't hold vacuum! but now my fresh air vents are working!
Just what is the procedure for checking the center vent pot? oh, and it looks like the heater box was repaired, can see a crack that was re-inforced with piece of aluminum.

Thanks,-DDaymen

rowdie · #15 12-15-2009, 11:14 AM

I think the center vent pod is inside the heater box. It requires dash removal. That is why most do not get repaired.