Ignition Lock

[rickmuzick]

Hi everyone...quicky question.

I have not driven the 450SEL (1980) for more than a month.
Today I went to start it just to get it running but the key will not turn and therefore it won't crank.

I have tried everything including recharging the battery and nothing.

Ideas?

Thanks again in advance!

Rick in Nashville

[rickmuzick]

 

Thanks Styria

Unfortunately I have tried that for about 15 minutes staright to no avail.

I am afraid I am going to break the ONLY key I have to this vehicle.

[oscar]

Hi rick,

I too thought it might be the steering lock but thought it might be too obvious to mention.  But then again, I remember my steering getting wound up so tight against the lock when I realigned my steering shaft, that when I tried to turn the wheel I ended up unable to tell which way i had to twist it so the key could turn.  It really took some force one way or the other to turn the wheel the right way before the key would budge.  Can you turn your steering wheel at all? 

My only other thought is that the key and tumbler are worn.  I'd suggest going and getting another key cut as sometimes the copy ends up with higher ridges.  So if the tumbler pins are worn, the extra height of the key's ridges will be enough to unlock the tumbler.  Get a couple cut and try them.  If that fails, it's either time to call a locksmith or have a crack at removing the tumbler yourself.  See how the copied keys go first.  Good luck.

[Andreas]

If you have had a sticky key in the past it is definatley a worn tumbler. The tumblers rarely fail all of a sudden according to my Merc dealer here in Adealaide. One usually has a warning of the impending problem. However as mention before if the key did not move freely before (ie you had to wiggle it occasionly to start the engine) it will be a tumbler. If you get it to move and you susspect it is the tumbler DO NOT REMOVE THE KEY and TAKE THE KEY PAST THE ACC POISTION  as this is the only position to remove the tumbler with ease and at no cost. I had this problem with my 6.9. Fortunatley the tumbler did not fail on me and I replaced it before it failed. If the tumbler fails it is a very difficult destructive and expensive job to replace.

Cheers and good luck

Andreas

[koan]

rickmuzick, don't give up on it yet. I had the same problem, at first the ignition key wouldn't turn occasionally, every couple of months or so, then every week. The last time took a good half hour of trying before it moved.

The real problem as andreas said is you need to be able to turn the key to get the old lock out but you can't turn the key because you need a new lock., a real catch-22.

I finally ordered a new lock barrel and a pair of new keys from MB, give them the VIN and they will make correct keys that fit the doors, boot and your new ignition lock. I think they have to come from Germany so there could be a bit of a delay.

Try jiggling the key back and forth and side to side, try the other edge of the key, try giving the key a tilt up or down or to the side as you inset it. Don't use a lot of force, if it's going to move it will move easily. Use plenty of spray lubricant down the key hole and round the barrel.

The basic procedure for getting the lock out is to get the key to the "II" position, push a piece of stiff wire down the hole to release the catch, then unscrew the black bezel around the lock and barrel will lift out. There are variations in the design over the years but that's basically it.

If you can't get the key to turn the lock will have to be drilled out.

koan

[rickmuzick]

 

Thanks everyone for the replies!

However, I have never had any problems with the key switch in the past. I have always been able to insert the key, turn the switch and start the engine.

On this particular model (450SEL) does the stickshift lock in place when the wheel locks? Mine is able to move, but I am not sure that is something that it did not already do in the past.

This is a real puzzler. I have done as stated above and put "a lot of pressure" behind trying to turn the wheel and the key switch, but nothing.

[s class]

To make sure its not your steering lock, try lifting the front wheels off the ground.  While the front of the car is safely supported, try again with the key. 

Ryan

[oscar]

On this particular model (450SEL) does the stickshift lock in place when the wheel locks? Mine is able to move, but I am not sure that is something that it did not already do in the past.

That's normal.  There's no lock on the gear selector at all.  Ryan's got a great idea there. That'll decide once and for all if it's got anything to do with the steering lock.

[rickmuzick]

Ryan what will ,lifting the front wheels do?

Thanks Rick

[Papalangi]

Ryan what will ,lifting the front wheels do?

Thanks Rick

It will take the pressure off of the lock.  If you have a wheel up against a curb, it will be very hard to get the column unlocked.

Michael