Argh! Ignition switch tumbler problems
 

I've lost my ignition key.

I got a new tumbler from Mercedes which comes with the original key. Can't get the old tumbler out.

I've read alot of howto's and help pages that all begin with:
Insert the old key and turn to the first position. This is no help because I've LOST THE KEY.

Now what?:(

Pick the lock. Failing that, a good drill and drill bit.

Honestly if you can get hold of another lock mechanism, remove the cylinder from that, install your new cylinder and then replace the good lock mechanism into your steering column.

Getting the lock cylinder out of the lock mechanism is by far the hardest part, not impossible with things in-place but very difficult and frustrating.

With a replacement lock mechanism you can either attempt to remove the problem lock mechanism in-place (grinding down its securing pin) or remove the upper steering column entirely and then remove the problem lock mechanism on the bench. If you decide to do the job with things in place this time, you'll almost always decide to remove everything and do it on the bench in the future!

No lock is "pick proof" but these Mercedes locks are very, very difficult to pick. 8 or 10 leaves and often times at least one pair of split leaves, that means one of the normal brass leaves is replaced by a leaf that is made up of two parts so that the cylinder won't be able to turn unless the key's upper and lower cuts simultaneously disengage the two leaf halves both the upper and lower. You'd have to pick the topside free then while holding tension to keep those leaves, find and access only the troublesome "half leaf" of the opposite key track.

Hmmn didn't know they are that hard to pick. Is the ignition tumbler more pick proof than the door tumblers? I was never able to take apart an ignition tumbler (lmk how if you've done it), but I have taken apart door tumblers and do not recall it having 8 or 10 leaves with a pair of split leaves.

good vibrations
 

May sound crazy- BUT it did work! Key didn't turn in tumbler in 300sd one afternoon during downpour in Walmart parking lot. Hmmm. Sent wife in to buy a battery powered tooth brush. took off brush, put metal against key and jimmied it for a while and presto, turned key/started. Got home and immediately removed cylinder and ordered new one...just my 2c.
M

Sounds like PO lost his only key. No amount of vibrating will help.

new key doesnt work in the locked tumbler?

Well first I have to say I didn't realize the OP was probably dealing with 123 car and that would be a two track key.

When referring to "split leaves" those would be next generation cars, maybe some earlyier 126 cars but definately all of them after 85.

http://s25.postimg.org/556cqegbv/Mer...linder_001.jpg
http://s25.postimg.org/rie3d7h9n/Mer...linder_002.jpg
http://s25.postimg.org/g3hm8l4x7/Mer...linder_003.jpg

This picture is a lock cylinder with a four track key it has 7 leaf positions, 3 of which (2,3,4)are split leaves for a total of 10 individual leaves.

I pulled out the three pairs so it can be seen how they are different cut-outs for different heights. Very difficult to pick because key is 3mm wide and each keyway track is 1 mm on either side. So first you'd have to pick at least a pair of leaves keep holding tension on them then soften the tension without releasing what leaves you've already picked and then pick the the 180 degrees opposite leaves with TWO pairs of split leaves! All the while preventing the first set from dropping while doing that.

On a early two track locks I think there are 8 leaf positions but again its 4 up and 4 down so that takes a surgeon's touch with the tension tool.


There is a very cool tool for the two track loks known as a "LISHI" I think the #68 is for some of the two track locks I don't know if it's the early external profile like a 123 key or a later indent profile like a 201 key but it's a pretty nice piece of tool making. There are some You Tube videos of it being used.

If you disassembled a door lock and removed its cylinder keyway then you know how the ignition cylinder is fundementally constructed, the same difficult part of getting the door lock apart is required on the ignition lock just in a different position and without being able to come at it from the opposite side. A very fine puller needs to be constructed using a tiny tap.

Key might fit. . .
 

Foolish question, but is the tumbler in the car (which model?) the original one? If so, the key will fit the tumbler.

If you ordered the tumbler through the dealer AND they tumbler is original, there is no problem.

If it is not the original tumbler, it is not impossible, but close.

I have removed the tumbler with a broken key stuck inside it.

Not easy, but possible.