Ignition Lock/Cylinder Removal Procedure: Where in manual? - PeachParts Mercedes-Benz Forum

#1 06-21-2006, 02:26 PM

Just a quick and stupid question. Where in the MB service manual can I find the procedure for replacing the ignition lock cylinder? I can't seem to find it. I have the CD for the w116 chassis.

janko · #2 06-21-2006, 05:57 PM

'dieselgiant' has a good write up on subject. suggest a search. his take may be better than the factory info. hope this helps.

jbaj007 · #3 06-21-2006, 08:59 PM

It's in the steering section. 46-460 in the w126 manual; probably close to that in the w116 manual.

F18 · #4 06-21-2006, 09:59 PM

Tabor,
Can you still turn the ignition lock cylinder with the key? Or is the lock cylinder worn out to the point where it won't turn anymore even with a new key? I believe the ignition lock system was the same from the 70's through the 80's.

On my 84 300SD the key had to be turned to position 2 and a lock pin compression tool slid down the side of the cylinder( there is a channel along the cylinder for the tool to fit and yes you can make your own tool) to release the cylinder from its housing. I believe there is a a trim collar on the ignition lock that needs to be pried off first to see the tool slot.

If the cylinder cannot be turned to line up the locking pin with the tool slot in the housing the whole mechanical steering wheel lock and ignition cylinder ( which are tied together) remain locked in place. Its a great anti theft system until the the lock cylinder fails......then you need to invest in some titanium tipped drill bits...I've been there...its not a happy place to be!

This is from my memory so forgive me if its not real detailed...

#5 06-22-2006, 02:38 AM

I found dieselgiant's write up on how to replace the cylinder if you can't turn the key. I just wanted to know how to replace it if you could. I am contemplating buying a cylinder from the dealer so that my door key and my ignition key match. My cylinder has been replaced by some cheesey aftermarket unit.

Hypothetically, if the cylinder were to fail, do I just stick a drill bit in the center of it and go at it? I have a good set of carbide bits, will that do? Also, had anybody tried brute strength to break it? That is sticking something like an offset screwdriver in it and applying a lot of force. I once talked to a guy who claimed to have experience with such things that said it had never failed him. Of course, all he cared about was that the car started.

EDITed for grammar.

F18 · #6 06-22-2006, 08:32 AM

Tabor,
It sounds like someone at one time just replaced the old stock lock cylinder with one the MB mechanics sometimes refer to a "shop ignition cylinder" It would have just a standard saw-toothed cut key like you would have on your dad's Buick instead of a Mercedes 3D Key. They sometimes pop those in while they are waiting on the delivery of the vin number matched replacement

All I can remember from 10 years ago when I had the problem of a failed cylinder is drilling all-day-long...and I had some advise from a MB mechanic which did not help much. That is one tuff tuff unit....I guess thats why its a proper theft deterent... As far as where to drill, I remember trying to drill into the housing where the locking pin might be, but it was in a tough postion and a number of other things had to moved or removed.
I hope the DieselGiant DIY info will help you!

jgroover · #7 06-22-2006, 03:52 PM

I just had to remove the entire ignition assembly on my 123 becuase the tumbler was stuck and in frustration i broke the key off inside of it. If you can't get just the tumbler assembly out it is a pain but not that bad of a job looking back on it. My problem now is that i don't have a replacement tumbler/ignition system and since i don't have a spare car i just took the ignition switch part and wired that back up so i just turn that with a screwdriver.. no tumbler assembly is there at all.

Works perfectly... so now i'm thinkin if i get time maybe i'll make a couple toggle switches and a push button for start up

would be pretty cool