Passenger Door Pull

[Charles 230SL]

Hello all,
My passenger 'door pull' has been missing since I've owned the car and I'd like to try and install one without removing the door panel. Would anyone happen to know where I could find measurements for the red X's in my photo below? Installation of a passenger door pull has been discussed several times over the years but I can't find any measurements for the four screw holes. I want to make sure I get the holes marked correctly before I puncture the leather. thanks in advance for any info, Charles

[dirkbalter]

Charles.
My panels are removed. Unless someone chimes in before, I can send some dimensions tonight.

[Jordan]

Charles, have you tried feeling around the surface with your fingers?  If memory serves, the hardboard behind the vinyl/leather cover has holes in it where the door pull is screwed to the door.

[MikeSimon]

Isn't there a metal piece behind the panel, where the pull mounts to? Seems strange that it would pull at the panel.

[Charles 230SL]

..have you tried feeling around the surface with your fingers?  If memory serves, the hardboard behind the vinyl/leather cover has holes in it where the door pull is screwed to the door.

Yes, I've tried pushing in/around the area with my fingers but I can't detect any holes in the hardboard. I'll use a blow-dryer to heat the leather and see if I can feel the holes once the leather is more pliable.  Dirk, it would be great if you could post dimensions/measurements for the (4) holes. thanks in advance, Charles

[mbpaul]

Although there are no dimensions, if you go to ebay and look for "Mercedes 113 door panel", there are some pictures of used door panels with the holes shown.  Not exact but you can get a better idea of where the holes should be.

[BobH]

https://www.sl113.org/forums/index.php?topic=18284.msg155893#msg155893

Have a look here at post 1440. The door pull screws into these threaded holes in the frame, no dimensions, but the holes in the door lining need to line up with these threaded holes

[Charles 230SL]

thanks Bob, great photo from Andy Burns - I would have never found it.

The more I study the photos the more I realize I'd best go ahead and remove the door panel - looks too risky (punching through the leather and 'fishing' for those screw holes).  thanks again,, Charles   

[BobH]

https://www.sl113.org/forums/index.php?topic=16914.msg119256

Hello Charles, if you're going to remove the panel, have a look at post 6 for a tip on how to mark the hole positions, probably the most fail safe method

Good luck!

[dirkbalter]

May be that helps. As Mike already said, you should be able to feel the soft spot
Let me know if you need anything else?

[dirkbalter]

Mounting in the door

[dirkbalter]

And (new) panels.

[Charles 230SL]

Outstanding! thanks Dirk!

[Jonny B]

I would recommend you check the condition of the threads in the door. When Mrfatboy and I were doing some work on the windows last year, I discovered that the threads were in pretty sad shape. I ended up going one mm larger as the threads were stripped out (using a sheet metal screw no less!). It was so iffy, that it was a standard warning for any passenger to never use the door pull. Now corrected., albeit with one size larger machine screw thread.

[Charles 230SL]

I would recommend you check the condition of the threads in the door..I discovered that the threads were in pretty sad shape.. I ended up going one mm larger as the threads were stripped out..Now corrected., albeit with one size larger machine screw thread.

thanks Jonny., yep, I thought about that (threads being stripped out). I'll be prepared to cut new threads in the door frame. The door frame appears to be aluminum in Dirk's photo - are the threads for the pull handle cut into aluminum or steel?

[dirkbalter]

Yes, checking the threads and repair if necessary is good advise. They are tapped into the aluminum.

[mdsalemi]

In my case on the door pull for the driver side which of course is also the armrest, I too had a situation where the threads were too weak and eventually stopped working. The whole thing just pulled out on one end.

The first repair done by my mechanic was with a steel rivnut. That worked briefly but eventually pulled out. For the second go around they brought out the big guns: using an aluminum welder they filled the hole completely and then re-tapped it.

The beauty of this repair was they were able to add more metal than was there originally thus giving more threaded area. So it’s a stronger fit now.

[Charles 230SL]

Well, since the threads are tapped into aluminum, they're most likely stripped out - which may explain why Bud's didn't install the pull handle when they trimmed/upholstered my interior 8 years ago..
I've got access to a TIG welder but I'd rather not strip the door down and attempt filling in the holes. Is there enough room to epoxy nuts on the backside of the frame and use screws to secure the handle? (I've not removed the passenger door panel yet and that's the reason for all the questions).

[dirkbalter]

The threads are M5 but I can check to be sure. If they are stripped I would just drill them out and tap M6 as suggested. It looks like there is enough room to clear the bigger bolt heads. There are other ways from rivet nut to threaded inserts…. Not sure I would start welding on a finished door.

[wwheeler]

M5 helicoil will work just fine. I have used those in a few places in the cast door frame. Buy the set that comes with a drill, tap and inserts. One word of caution - use thread lube when tapping. The super soft door frame alloy will gum up the tap and wreck the threads when pulling the tap out. Ask me how I know.

[Pawel66]

I would have thought they are M4. M4 heli coil set will work just fine.

[mdsalemi]

As I recall, the challenge with the rivnut on mine was that if you look at one, what holds it in place and prevents it from "spinning" is a very mild splining. Well, it really didn't take much torque (a/k/a shear  or twisting force) to rotate the rivnut in the now newer and larger hold drilled to accept it.  . Rivnut makes hex shaped rivnuts, but they require a hexagonal hole. I seem to have lost my hexagonal drill bit  ; but their installation instructions say, "...laser a hex hole into your parent material..." Oh, yeah, I'll just go to the back and get the high powered laser to cut a hex hole...

Not certain why my shop didn't try a helicoil, I know that as a serious mechanic shop, body shop and restoration shop they surely had all of these "fixes" laying around.

The overriding issue here is the "parent material" that we're talking about--the door frame--is extremely soft material and doesn't put up with repeated installation and removal of screws. Otherwise we wouldn't be talking about this!

For many amateurs, the thought of bringing out a TIG welder on a finished door may be daunting. For professionals it was no big deal. Filled and re-drilled and re-tapped.

[Pawel66]

I used rivnuts in a lot of places requiring high torque fastening - never had any issues. The difference may be if they are aluminum or steel. But anyway it is not only the spline that holds them in place and prevents from spinning, it is more the crimping force applied during installation. You need to have proper riveting pliers (or what is the name of this device in English?).

I also do not think that the frame to which door handle attaches is a good place for rivnuts, particularly small diameter ones. They would be too short and the frame too thick to crimp them properly. These rivnuts work on metal sheet, not a bar type of frames.

I do not, however, recall seeing M4 rivnuts. I also think helicoil (or alike) is the best solution for the particular place in question. Or re-threading if possible.

[dirkbalter]

As I recall, the challenge with the rivnut on mine was that if you look at one, what holds it in place and prevents it from "spinning" is a very mild splining. Well, it really didn't take much torque (a/k/a shear  or twisting force) to rotate the rivnut in the now newer and larger hold drilled to accept it.  . Rivnut makes hex shaped rivnuts, but they require a hexagonal hole. I seem to have lost my hexagonal drill bit  ; but their installation instructions say, "...laser a hex hole into your parent material..." Oh, yeah, I'll just go to the back and get the high powered laser to cut a hex hole...

As Paweł already said, you need proper pliers to “rivet” the nut in place. Just Pushing or pressing them in and rely on the splines for fastening is not going to cut it.

[dirkbalter]

Just checked, Paweł was correct, the threads in question are M4.