How does vacuum element attach to door lock rod?
 

It's been about a year since I removed the one of the rear door vacuum door lock elements to repair it. I now have the vacuum element sitting here waiting to go back in but for the life of me, I cannot recall how I removed it from the bottom end of the door lock rod.

The end of the rod that attaches to the vacuum piece is threaded. The top part of the vacuum element that the rod feeds into is also threaded. No brainer, right?
Well, the rod is bolted down against the door frame so it can't move around much at all. In order to thread the rod into the vacuum element, I would have to spin the entire vacuum piece...but that can't happen since there's really not enough room to do this since it would mean that the rod would have to flex around quite a bit.

How the heck did I get it off to begin with? (since this would obviously involve UN-threading the rod. Is there a trick to this?

Not sure whether you are talking about the front or rear door. I took a look at an old picture of my original blue actuator (rear door) from my 81 300SD. The top of the rod is flat with a hole in it and I think that something from the door lock near the top hooked into the hole and was pulled up and down to lock and unlock. Do not remember the rod being inside a guide; think it just moved up and down freely inside the door - although it did have a couple of severe bends.

Either way I think you must remove the rod and actuator (in your case also remove the rod guide) to get the rod in or out. It is no big deal. Pull the hoses off the actuator and remove about three screws. It comes out easily and you can screw the rod back into the top of the actuator before sticking it back in.

Not sure how you got it out unless the white plastic plunger below the bottom threads was broken thereby releasing the rod from the actuator (the plunger is covered by a black rubber cover and slides in and out of the actuator) . That's what happened to mine. The actuator worked perfectly after twenty seven years but the white plastic plunger inside the actuator broke due to an inproper repair of the door check by my mechanic. Could not figure out how to repair the plunger.

Good luck. Just take the actuator out and do the fix. Most time consuming element is removing the door panel.

This one is from my 83 SD and you put the rod in and close the side of it. I also replaced the gas cover module on my car and on that one you put the rod in and pull a collar up to lock it. The rod in the picture is not the one that would be used in that module but is just there to see the fit.

I did this on my 85 300d, however the SDs are so different in terms of parts.

On my vacuum pod I had to pull the head down and the clip would come right off.


What did you use to replace the rubber? My pod is alright, but since the rubber is cracked I couldn't find anything to replace it with. I ended up buying a whole new one, but I feel bad replacing the whole pod since all I really need is replace the rubber that is on top of it.

This sounds very similar to what I finally discovered.
At the top where the rod would thread in...I thought...you could sort of pop it out of the tube. This section that contained the threads inside was actually about 1/4 exposed so that I could just push the rod inside it....and then push the whole thing back down until it was clipped back into place.

The most difficult part was figuring exactly how much of the rod needed to go in in order to have the element positioned properly....so that when it was in the unlock position and lock position, that it could go all the way up or all the way down properly.

Thanks everyone for the ideas and help!

But but but! What did you use to replace the rubber? I would love to get my door panel back on like today. I feel naked driving with the interior taken apart.

Replace WHAT rubber?