124 ignition barrel / tumbler removal (key won't turn)

[Williamwoo]

Hi all,

Help! The ignition tumbler/barrel of my 124 has been gradually getting harder and harder to turn for a while now, and I recently ordered a new one which arrived the other day. Unfortunately, since then, it has stopped turning at all. I have tried:

• As much force on the key as I dare
• Applying grease and WD40
• Pulling the key out fractionally
• Twisting it in every imaginable way, both slowly and quickly
• Rocking the (locked) steering wheel
• Vibrating it with the pointy bit at end of an electric toothbrush (sans brush) while twisting the key
• Tapping the lock
• ‘Building the key up’ using nail varnish (wife gave me a funny look!)
• Swearing
• More swearing
• Etc etc etc

And I just can’t get it to budge.

I have of course perused these pages, and those of lesser sites, and looked at many Youtube vids, but have seen conflicting advice and am unsure what to do next. My thoughts are:

• Remove the black metal ‘collar’ the tumbler sits in (I’m quite handy with a Dremel). If I do this though, does it give me enough access to remove the tumbler (doesn't matter if I have to destroy it as I have the new one)?
• Hammer a chisel into the lock and turn it using whatever force necessary. What would be likely to break first, anyone know?! (I suspect though that the twisting action may cause the chisel to twist out of the lock.)
• Drill the lock out

Any thoughts or suggestions gratefully received, thanks.

 

[190]

From the vague memory of doing this on my 190e there was a special tool a bit like those used for the old radio removal. Basically thin metal rods that were pushes down the sides of the lock. The lock may need to be in a certain position before the barrel will come out.

From disassembly of the lock barrel I determined the basic problem was the lock pins and or the key wear such that the lock pins are not moved quite far enough for the lock to operate. That being the case you have to do something to compensate for the wear. I re-ordered the pins leaving the shortest one out and it worked for 10 years or more after that. But you have to get it out first. Do you have another key that might not be as worn or you could try heating the key, it won't expand much but might be worth a try.

 

[SMS]

The release “holes” can only work when the key is turned to position 1. That goes for all the ign theft locks. Keep trying to wiggle key, the tumbler section of barrel snaps and moves away from inserted key, so it thinks wrong key is inserted.

 

[wrdcc01]

I've had my 124 stolen twice over the years and both times I got it back with a broken ignition lock. there was no scratch, cut or impact damage or markings but the lock rotated freely without a key and the steering lock peg was sheared off. I guess the steering wheel had enough movement to allow it to be jerked hard enough to break and the lock barrel was just forced with a screwdriver or the like. You could call the above "plan C"
Maybe try a key cutters and see if they could cut a key that doesn't follow the exact profile, keeping the high points a little higher to compensate for the wear. When you are wiggling the key make sure you are always holding the steering wheel off the locking peg.

 

[neilrr]

There are dozens of threads to do with this problem on this & every MB forum in the universe. Search for 'barrel' to start.

 

[Williamwoo]

Thanks for all your replies.

190, what you're describing is great so long as the key can be turned to position 1, which mine can't (as SMS has alluded to).

Wrdcc01, sorry to hear that you've had yours stolen twice. I didn't think it was possible to break the steering lock peg simply by yanking on the wheel. I wonder how they managed to twist the barrel too - impact driver maybe? Thanks for the tips on key wear though - however, I'm beginning to think something has broken in the lock as, until recently, it was possible to start the car with at most a minute's wiggling/swearing, but since then I've suddenly not been able to do it despite many hours of trying (and quite painful thumbs and forefingers).

Neilrr, thanks for the tip. I have found many threads and vids, but some are contradictory - some saying Dremel off the front of the black metal collar and the tumbler will virtually fall out, others saying this is not a good idea and suggesting drilling instead, some saying there's not enough room to get a Dremel in there if the column etc is in situ, differences of opinion depending on rhd/lhd etc. I'm no mechanic (and must admit I can't quite visualise yet how it all hangs together) but I don't mind getting my hands dirty and was just looking for what most regard as the best option. Mine is rhd and I think I'm going to try Dremeling the front off the collar.

 

[CHARLIE PEACOCK]

Thanks for all your replies.

190, what you're describing is great so long as the key can be turned to position 1, which mine can't (as SMS has alluded to).

Wrdcc01, sorry to hear that you've had yours stolen twice. I didn't think it was possible to break the steering lock peg simply by yanking on the wheel. I wonder how they managed to twist the barrel too - impact driver maybe? Thanks for the tips on key wear though - however, I'm beginning to think something has broken in the lock as, until recently, it was possible to start the car with at most a minute's wiggling/swearing, but since then I've suddenly not been able to do it despite many hours of trying (and quite painful thumbs and forefingers).

Neilrr, thanks for the tip. I have found many threads and vids, but some are contradictory - some saying Dremel off the front of the black metal collar and the tumbler will virtually fall out, others saying this is not a good idea and suggesting drilling instead, some saying there's not enough room to get a Dremel in there if the column etc is in situ, differences of opinion depending on rhd/lhd etc. I'm no mechanic (and must admit I can't quite visualise yet how it all hangs together) but I don't mind getting my hands dirty and was just looking for what most regard as the best option. Mine is rhd and I think I'm going to try Dremeling the front off the collar.

Use a carbit cutting bit and drill out the centre of the barrel be careful not to bore in to far, Use a bit of black tape as a marker on the shaft.

 

[Williamwoo]

Hi all,
Success!
In the end I decided to Dremel off the front of the collar. It wasn't as difficult as I thought. It took about an hour or so of Dremeling - access is not bad and you don't even need to remove the piece of trim that goes under the steering wheel (although you do need to undo it and pull it down a few inches on the left hand side). Once I'd got the front off, the tumbler came out easily, as did the remainder of the collar.
The only problem that I then had was that the new tumbler wouldn't go all the way in - it was cheap, bought off Ebay for a tenner. However, after comparing it with the old one I realised there were two extra metal 'tongues' that were stopping it. Not sure how helpful this pic is but, once I'd ground them down (Dremel again, obvs), it fitted perfectly and I'm a happy bunny.


Thanks again all for your suggestions. Happy Easter!

 

[oldguy57]

Very satisfying when you can resolve a problem yourself!

 

[Williamwoo]

Very satisfying when you can resolve a problem yourself!

Indeed! In my youth, I learned how to maintain and repair cars myself (out of financial necessity), and my old Merc is of an age that it is not so complicated that I can't do most things on it too, but my other cars - much less so!