Key will not turn ignition tumbler in my 85 300TD. Tried spare keys and same thing.

Any suggestions what to trouble shoot?

At this point I would assume you have tried releasing pressure from steering wheel against lock and tried a penetratin oil of some sort.
Others will chime in and if you search there is alot of info on this as it seems to be rather common in our aging mercedes. I lucked out and searched as soon as it happened the first time and used procedure found on this website to remove and replace. Import auto place in town had tumbler with key (Generic brand OE style) $75.00 I needed it immediately installed and now my car takes two keys. Dealer can Vin match lock and order as I recall $180.00
or higher its been a while.
I have read of people messing with steering wheel while vibrating sander "body" or "housing" (not sanding!) vibrating key till it freed up then immediately remove before you never get it to turn again. It has to be turned to position one for removal.


Several threads:

Ignition Cylinder Tumbler replacement; mixed diesel/gas

Procedure removal:
ready to cut ignition tumbler

Good luck

Arlo

__________________

W211 E550
HVAC/R Certified Technician

'dieselgiant' has a good write up on subject. Search in the forum for it. There is also a thread that describes the use of a palm sander as a vibrator on the key to loosen it up.

Most people seem to be able to free the key--long enough to get that tumbler out for replacement.

Good luck,

John Bonds '82 240D 4sp, 202k, daily driver (and recent installation of new ignition lock housing).

What they said. Also you may find that it is the ignition lock assembly and not the tumbler. There is a lot of information on the site for correcting both problems.

Thanks guys. Now I'm noticing the that only the driver's door locks and the remaining doors plus the hatch are staying unlocked. Is this related to my gremlin?

In my opinion the locks are purely coincedience or just noticed as you are being more observant right now..The locks are vacuum controlled and you may just be running out of vacuum since it has not been running. I am unaware if the 85 300TD has a electric vacuum pump for central locking system like my 87 300d if not you stored supply of vacuum may be out from you pressing the brake by habit while trying to get ignition to turn or some other leaks. The drivers lock is mechanically connected to the door tumbler so it will move with the key no matter what.

Arlo

__________________

W211 E550
HVAC/R Certified Technician

Key is not moving tumbler in any fashion whatsoever. The DYI are just beyond my limited knowledge and being memorial day weekend, there is not much I can do.

Tow truck to local Mb mechanic on tuesday morning I'm afraid.

Mercedes Raodside Assistance
Mercedes Raodside Assistance