w126 lock issue
Thread Starter
Joined: Dec 2007
Posts: 5
w126 lock issue
Today I put my key in my drivers side lock and turned it. Much to my surprise it turned completely free and did not unlock the door. It feels as if the tumbler has broken free. It turns completely from 9 o'clock to 3 o'clock with no frictions/tension. All other locks and vacuum systems operates fine. The sticky that was posted in the DIY section that searched posts for door locks point too is no longer a valid page. The other posts I found dealt with vacuum issues or tumblers that would not move at all. Mine moves just fine...too fine! 
So, does anyone have any advice on this issue? I want to get some feedback before I take the door and handle apart. Advice? Thanks.
1985 300sd
So, does anyone have any advice on this issue? I want to get some feedback before I take the door and handle apart. Advice? Thanks.
1985 300sd
Joined: Apr 2008
Posts: 45
RE: w126 lock issue
When you turn the key it is throwing a lot of levers and cams that make up the door latch assembly. It is also moving several rods that connect to the levers by plastic grommits.
The only way you are going to know what is going on is to remove the door panel and look at it. Make sure the glass is in the up positon before doing this.
You can remove the latch assembly by disconnecting the lock rods from it and then removing the screws that hold the assembly in place. As I recall there are three rods: One from the power lock assembly, one from the door lock and one from the inside door latch. I think there are also three screws that hold it in. You can see them when you open the door. They are above and below the door latch.
If your assembly is broken, and it sounds like it is, you will not need to remove the key assembly or the outside door handle. This is good because removing it and replacing the lock assembly is quite a chore.
I know on the 123 cars there is a spring in the latch assembly that breaks or slips off. You can likely replace this or rebuild the one you have. Get some spray lube and hose down anything that moves in the joints in the latch assembly until all parts move freely. This assembly looks like a three pound watch but is really very simple clean up and overhaul.
Replace all the plastic grommets with new ones and don't forget to put a small bit of grease on them (where they pivot) when you do.
Sam
The only way you are going to know what is going on is to remove the door panel and look at it. Make sure the glass is in the up positon before doing this.
You can remove the latch assembly by disconnecting the lock rods from it and then removing the screws that hold the assembly in place. As I recall there are three rods: One from the power lock assembly, one from the door lock and one from the inside door latch. I think there are also three screws that hold it in. You can see them when you open the door. They are above and below the door latch.
If your assembly is broken, and it sounds like it is, you will not need to remove the key assembly or the outside door handle. This is good because removing it and replacing the lock assembly is quite a chore.
I know on the 123 cars there is a spring in the latch assembly that breaks or slips off. You can likely replace this or rebuild the one you have. Get some spray lube and hose down anything that moves in the joints in the latch assembly until all parts move freely. This assembly looks like a three pound watch but is really very simple clean up and overhaul.
Replace all the plastic grommets with new ones and don't forget to put a small bit of grease on them (where they pivot) when you do.
Sam
Thread
Thread Starter
Forum
Replies
Last Post
GeorgeT
Mercedes S Class
1
Apr 30, 2013 05:49 PM
legenesepimp
Mercedes S Class
0
Nov 2, 2005 05:04 PM
