sliding window jaw
 

So my rear left window quits working. I take the trim off and see that the little plastic dealy (they call it the sliding window jaw) that holds the motor's arm to the window is broken, leaving the arm free to move about without moving the window.

I say, thank God it's not the motor (but I was kinda sure it wasn't since I could hear it), and go to the dealership and pay $8 for a new plastic dealy. I go to put it in, thinking it'll take all of 5 minutes, but surprise surprise, I run into a bigger problem.

The little plastic dealy is connected to the arm via a metal dealy. Half of the metal dealy comes with the sliding jaw, and looks like it's supposed to snap in to the other half, through a hole in the arm.

Now the problem is two-fold. First off, the metal dealy is perfectly cylindrical, so there's no way to twist it off or anything. Second, it seems like some sort of super air gun or something shot one part into the other, cause they are stuck like there's no tomorrow.

At first I didn't even realize they were two pieces, because when the plastic dealy broke, the metal dealy stayed together, in the arm. Then when it came time to hook to arm up to the plastic dealy, "oops, there's an extra part here".

So to make a long story short, does anyone have any idea how take the metal dealy off the arm? Is there something I'm missing? Do I have to get a new window regulator just because of that messed up cylindrical screw?

Gabriel

It's not a screw; it's a rivet. Grind off the end of the rivet at the arm, place new one, support the metal in the middle of the plastic and "peen" the edges of the "cylinder" over.

ok, I don't understand much of what you said. I don't know mechanic speak all that well.

How would I grind the end of the rivet off?
How do I place a new one? Where would I get the new one from?
The plastic came with the metal dealy already in it. I have no idea what peening means.

Gabriel

Gabriel,

I don't have much experience with rivets, and haven't had to do any window work on my Mercedes yet, but I can help you out with 007's instrux.

Grind the end of the rivet off with a Dremel type tool. You can get these at Sears or most hobby shops. It's just a hand-held electric tool with a variable-speed spinning shaft to which you can connect different bits - like small grinding wheels, polishing cloths etc. You'll pay 60 to 90 bucks for one. Depending on how much space you have to work with, you may be able to grind the end off with a file. That's the long method, but certainly cheaper than buying a new tool for this one job.
Try to save the remainder of the rivet when you remove it, take it to a hardware store - a real hardware store, not one of these places with pre-packaged screws - and ask the friendly old guy there what you need to replace that rivet. And show it to him. His name's probably Nick or Joe, and he'll be able to go to the aisle where the rivets are and the correct rivet will be in the first drawer he opens. He'll be able to sell you the tool you need to install the rivet, and if you ask him, he'll even show you how to do it.

Peening is simply flaring the end of the rivet after you pass it through the 2 pieces so that it won't come back out.

I might be missing something, but it seems to me that since this rivet is made of two pieces (one goes in the other) that there'd be a tool to separate the two pieces. I mean, whatever put them together didn't glue them together right? They're just in real tight.
The part that comes with the plastic dealy is one of the parts of the rivet (and God knows why it didn't come with both parts of it), but I'm thinking that if I can separate the old one, I can use the part that I'm missing.
That part looks like a thick empty nail. In other words, it's got the head of a nail, but it's thick and hollow so that the part in the plastic will fit into it. That part goes through the hole in the arm (but not all of it because of the nail head) and connects to the plastic.
So like I said before, I don't know much about mechanics... this is the first car I've done work on, but I catch on pretty quick and I like to learn, I'm just hoping I explained all this clearly. So if you still think I need to saw the end of it off in order to get it out I can do that. It just seems to me that it should come apart without going to that.

Gabriel

I'm almost curious enough now to take my door apart. But since time is always precious, and I've got several more critical repairs ahead of me, I'll have to defer to someone who's done this before. Sorry Gabriel.
These cars are built for the long haul and as such are usually designed to be repaired without going to extremes. It does seem logical that the engineers would design this part with some relatively simple means of replacement.

I have done this before and it seemed pretty straightforward. The part you got from the dealer (slider) snaps apart into 2 pieces. But be careful, there are some graphite rods in there that you need. When you snap it apart, you'll have one part with the rivet in it and one just kind of flat piece of plastic.

To install, I first ground the rivet that is still attached to the window (as part of whatever remains of that half of the old window slider). Once you have ground that out, it should fall right out of the window riser (your metal dealy, I believe). Insert the new one just like your old one was, and use a hammer to peen the end of the rivet. It will be sticking through the hole with some clearance. Just hit around the edge of the rivet to turn it down enough to hold it on to the window riser. After a while, it will no longer come back out of the hole. WHen you've done that, snap the other half of the window slider onto the new one you just attached, and you're ready to reinstall it into the window channel.

It seems like an inelegant way to do this, but it's the way MB chose. The hardware store might have a rivet strike attachment that one could put right on the end of the rivet to force a better peening, but this is the way I did it and it has held for over a year at this point.

Ok, so by grinding it out, you mean cutting that rivet off, with the Dremel, like someone else said?

Gabriel

Yes. You just need to grind down the part that is holding the rivet in place. It goes through the hole, then was peened to hold it in place. I just hit it around there to get rid of the part that was knocked down to hold it in, and it slid right out.

Ok, one last question. I don't wanna spend the money for the Dremel right now, so how do I get it off? File, or something like that? or a saw?

Gabriel

I didn't have a Dremel when I did this. I believe I just pushed the rivet through as far as it would go, and used a file. You're essentially just filling off the burrs that were put in with the peening until you get the remaining rivet back down to its original diameter. Then it will slide right out.

Here a picture
 

of the nylon "sliding jaw" p/n 126-720-01-42. I picked it up today at the local dealer. They have them on the shelf. Looks like it should be pretty straight forward. This is needed on my friends car that I put a new right rear window in a couple weeks ago. This piece is busted in there.

Jim, yeah that's the part. I already picked it up. It's not problem putting in the sliding channel. The problem is that metal part visible in the picture (the rivet) which is attached to just the arm now, since the plastic part broke. It's a pain to remove it from the arm.

Gabriel