Driver's door inside handle return spring and key lock MALfunction

[Tomnistuff]

I lived with a long term problem of not being able to lock my driver's door with the key, and having to lock it by walking around the car and crawling in the passenger door to use the inside remote lock switch (Mercedes-Benz name or something like that).  The passenger lock worked well with the key, so it was tolerable, if annoying.

When my driver's inside door handle stopped returning to its closed position and just flopped, I did a search on the Pagoda site and found a piece of "gold" in al_lieffring's "Inside door handle spring repair" writeup.

It worked like a charm to fix the "floppy" door handle.  Since the latch was removed to fix the spring, I attacked the "key not locking the door" problem, but two days of experiments and analysis has been fruitless.  I even opened up the passenger door (removed the door panel) and have been trying to compare their functions.

If I just insert the key and try to lock the closed driver's door, the key meets no resistance, and does not lock, but if I push in the button 1/2 way with the key and turn it toward "lock", It turns about half way "45 deg", then stops up against the small V-shaped knob on the latch shaft inside the door that is supposed to unlock the door and will turn no further (for fear of breaking the key). 

Is it possible that the penetration of the striker housing is not quite enough to adequately push in the small mechanism lock-tab at the extreme end of the latch receptacle cavity when the door is closed?

I'll test that tomorrow but beyond that, I am out of ideas.  Any ideas or advice?
Tom Kizer

[ja17]

The door closing mechanism has two positions. The first position is "almost shut". In this position the door lock will not work. The second position is "all the way shut"(position 2) and the lock function should work. Make sure your door reaches position 2. If not loosen the fastening screws on the door cone (on the door post) and move it outward.

[Tomnistuff]

Hi, Joe.
You were right, as usual.
Your comment answered what I was trying to ask in the last line of my post, but you said the answer a lot clearer than I posed the question.   I did what you suggested and managed to find a "striker position" that permitted the key to lock the driver's door.  With the door closed and unlocked, I have to insert the key, push the button half-way in until it hits a hard resistance with the "fully inserted" key, then "bias" the key in the lock direction (It still won't turn.)  Then, while allowing the button to come back out slowly until a slight turning movement of the key is detected.  At that point, I then forcefully turn the key farther to the full lock position.
It is tricky but consistent. 

It feels almost as if the tiny  "lock out" tabs are not pushed far enough into the latch to really permit the key lock mechanism to be free to turn and lock the door.

A closer examination of the striker housing that receives the "cone shaped pin" of the latch revealed that the part of the striker that contacts the little "lock out" tabs has a slot worn into the contact point.  That worn slot is slightly more than a tenth of a millimeter deep.  See the photo.  That certainly can't help the situation.  Thanks for the help.  I'll look for a better striker.
Tom Kizer

[rwmastel]

It looks like that interior part made of a different material could be replaced with proper tools and an impossible to find good replacement part.  Time for a whole new part?

[Pawel66]

If it is not about alignment and the decision is made to source new parts, the door lock catch of earlier versions (three holes) is available at SLS (ca EUR 100).

I decided to replace both sides with replacement parts form Mercedes (late version). My life has changed in terms of - the sound of locking doors, door rattle as well as the key operation. Worn bushing inside the rubber in the catch apparently may affect a lot of things.

[Tomnistuff]

Thanks Rodd and Pawel.  I found that Authentic Classics has both beautiful new Strikers for what I think is a reasonable price for a 58 year old classic car.  I'll probably order them today when I get back from re licensing my Pagoda for the winter (to avoid the mandatory winter tire purchase and installation as well as half the insurance cost here in Quebec, Canada).  I can't really use it significantly between November 1 and April 1 anyway because we get between 200 and 300 inches of snow each winter.  It will sit in the heated garage and be warmed up occasionally to keep the A/C exercised and the A/C seals lubricated.

Pawel, I am hoping for the effect that you describe in your second paragraph.

Tom Kizer

[Tomnistuff]

I just ordered one left door striker. Although showing damage similar to the driver's door striker, the passenger door striker currently works fine and sounds and feels good.  When it arrives, if the driver's door improves to be better than the passenger side, I'll order another for the passenger side as well.

Wish me luck.

Tom Kizer

[ja17]

Don't be afraid to use some good synthetic grease on the receiver, it will do wonders. The receiver looks like it is slightly worn on the bottom, which indicates to me that the door may have sagged or been mis-aligned at some point. Stand back and look at the body lines on the door and adjust the door or striker as needed. The cone on the door jamb is adjustable as you know. Loosen all the screws and retighten them to "just snug". By closing the door now, the cone will move into correct position with the receiver, in the door. If the body lines look good, then tighten the screws down all the way. If the body lines are bad, you may have to adjust the door at the front hinge, then repeat the process. 

[Tomnistuff]

Joe, I wish I had your experience and talent.  To me, the ability to adjust doors is a magic that I don't have.  Every time I even look at a door hinge, it seems to go out of adjustment.  My driver's door currently fits better than it has in years, but perhaps only because the door panel is currently removed.  I will observe again once I give up and put it back together with the new striker.
Thanks for the advice about the latch adjustability.  You were wrong  - I did not notice that it is adjustable.  Thanks for the technique.

Tom Kizer

[Pawel66]

To see what part of the striker hits which part of the catch and what hits what first, you may place some painters masking tape on the edges. You will see what stands in the way...

[Tomnistuff]

Hi Powel,

I am familiar with using masking tape stretched across the striker hole and a tiny bit of colored (not clear) grease on the tip of the cone shaped latch pin to center the pin in the striker hole, but, I am not sure I understand where you mean by "on the edges" or what you mean by "what stands in the way", or how to determine "what hits first".  This is a very interesting and potentially productive subject about a technique ripe for exploitation.

Do you suggest using tape and grease to mark other potential contact points?  like the lower door panel chrome retainer strip where it can potentially contact the chrome door sill carpet retainer, which also hides some wiring that runs between the front and rear of the car?  Or maybe between the door and the end of the instrument panel.  All around the outer edges of the door panel and inner edges of the car's door opening are potential contact points that can affect door positioning.  I have never really explored these possibilities, but may have to.

Thanks for the suggestion and any further details of the techniques that you might provide.  I now have all winter to think about these issues and develop improvements.

Tom Kizer

[Pawel66]

Tomnistuff, this is nothing really peculiar - simply, if there are two parts where one needs to relatively precisely fit into the other, they misalign over time and do not fit so well (which you may hear or feel while closing the door), applying masking tape on the edges of the catch part and closing the door will create marks on the tape that will allow you to see where the striker part gets in contact with the catch in a way that is not desired. You do not even need grease.

If you want to determine where the tip of the cone is vs. the center of the bushing catching it - yes, this is where, if you plaster the hole with tape and put some grease on the tip, you will see exactly where the misalignment is. Otherwise, in other places, you will see it even without grease.

Yes, the tape will show you marks of parts potentially getting in contact with each other and it will show you where they do not get in contact - no marks in tis case. It is a non-invasive method, pretty clean.

It may not help you in door adjustment, it will not tell you how wide are the gaps. But if you hear or feel rubbing of parts, it may help determine what is rubbing against what and how hard. 

[rwmastel]

Wouldn't it be smart to only tape the cone?  Not only do you learn the position of a misalignment, but also the severity of it by how close to the tip the interference begins.

[Pawel66]

Yes, you would see it, just close the door slowly.

[Tomnistuff]

I received and installed the new door latch striker for the B-pillar of the driver's door.  With the new striker, the door still closes well and still locks with the key exactly as I described using my original badly-worn striker in my response to Joe Alexander on October 23 (above).

Even though I have owned my car since 1987, until now I have not been able to lock the driver's door with the key as intended by Mercedes.  At least, I can do that now, however, there is something that I do not understand.  I suspect that it is not functioning correctly, although I am making it work, so I will ask here.

First, I will describe the key locking function of both the passenger door and the driver door of my car.

The passenger door can be locked or unlocked using either the inside remote control switch near the inside front of the passenger door or using the "squarish shaped" key in the outside passenger door button, but if locked, the door cannot be opened using the inside door handle unless the door is first unlocked with either the remote control switch or the "squarish shaped" key in the outside driver door button.  It does not matter if the door is open or closed when locking the passenger door using the inside remote control switch or when locking it using the key on the outside.  Equally, if the door is locked, it can be unlocked with either the key or the inside remote control switch near the front of the door.  And when using the key to either lock or unlock the passenger door, the key must be fully inserted in the buttonbut the outside door handle button does not have to be pressed in at all before turning the key to unlock or lock the door.  I think what is written in BOLD letters is as it should be, but am not sure.

Like the passenger door, the driver door will also lock and unlock using either the inside remote control switch near the inside front of the driver door or using the "squarish shaped" key in the outside driver door button.  Also, like the passenger door, the driver door cannot be opened using the inside door handle unless the door is first unlocked with either the remote control switch or the "squarish shaped" key in the outside driver door button.  Unlike the passenger door, the driver door cannot be locked when the door is open.  Even the remote control switch does not lock the door if the door is open.  This feature is apparently present to prevent the driver from locking himself or herself out of the car.  The driver door must be closed for the door lock remote control button or key to lock the car.  That also assumes that if the door is closed and the car is to be locked, then the window will be closed and if the driver wants to lock the door, he or she will have the key with them.
Finally, unlike the passenger door latch, to lock or unlock my driver door with the key, it is necessary to insert the key in the latch button completely, then using the key, push in the button about half way until a "semi-rigid" resistance is felt in the button movement, then turn the key clockwise (to lock) or counter-clockwise (to unlock) the door.  I suspect that this BOLD sentence is not as it should be.  It seems too tricky to be a Mercedes designed-in function.

The primary purpose for this long and detailed explanation of the function of my Pagoda door latches is to provide a background to help someone answer the following questions.

Is it normal to have to partially push in the door latch buttton on the driver door before turning the key to lock or unlock the door, or is there something broken or maladjusted in my driver door latch.  If yes, what might it be?

Does anyone notice any other "strange functions or behavior of my door latches"?

Thanks for any advice or even observations that you can provide.

Tom Kizer

[Duncan200]

Hi Tom,

To me it sounds like the rod that comes out of the door lock barrel needs to be lengthened on your drivers door lock so the “V” shape (could be an A shape, can’t remember which way it faces) on the end of it engages with the lock mechanism. By you pushing the button in with the key, you are effectively pushing the “V” shape in to the lock mechanism.

You would need to remove your outer door handle (two screws) and you will find a flat head screw on the opposite end of the door button. You use this to lengthen the rod.

I’m not home right now, but when I am, I’ll post some pics.

Doug

[Tomnistuff]

Hi Doug,
You are right.  I went through my many Pagoda photos and found photos of the inside of the two doors showing the engagement or non-engagement of the door handle rod with the door latch shaft.  What I think you called the V and the A shapes.  The Passenger door photo (outside door skin on the left) shows the V and A shapes are fully engaged but the driver door photo (outside door skin on the right) shows the V and A shapes are not engaged with a gap about equal to the amount I have to push in the button to get engagement to lock and unlock the door with the key.

All these years of owning the car and not knowing it could be so easy to fix.  I just assumed that there was something broken in the door latch.

I'll attack the problem tomorrow afternoon.  I have the door panel off already from the effort of repairing the broken spring and replacing the striker plate.  I'll post the results of tomorrow's efforts tomorrow evening if I finish and it works.

Thanks much for your help.

Tom Kizer
Quebec, Canada

[Duncan200]

Hi Tom,

Glad to be able to help you out.

Here are the pics of the flat blade screw I was talking about that you use to lengthen the rod.

I called it an A or a V because I guess it depends on which door it is fitted to, either way I’m glad you worked out what I was trying to describe.

Doug

[rwmastel]

I think what is written in BOLD letters is as it should be, but am not sure.

This is one of my favorite aspects of Pagoda gatherings.  Owners going around to other cars to see what "should be".  The adventure of discovery is a lot of fun for everyone!!

[Tomnistuff]

It worked like a charm.  No fiddling around required.
I extended the rod of the door handle shaft “V” by 7 mm, leaving 1 mm free play of the button before the “V” contacts the driven end of the latch shaft.  Everything works beautifully like it should (like the passenger door), except for the “no lock out” feature which also works.
I can't believe that after owning this Pagoda for 37 years and restoring it mostly alone, I am still learning how it works.
Thanks all, especially Doug.
Here’s the new handle-to-latch engagement photo.  I tried to attach a video of the new unlocking and locking operation but my "mov" video was not allowed.  Anyway, it works like a new car.
By the way, I agree with you, Rodd.

Tom Kizer