Mercedes 300SD ignition switch stuck. Help removing.

About a month ago, the key on my 1984 300SD got stuck in the off position. I did my homework and got it to turn THAT LAST time (after about an hour of trying.) So I removed the tumbler and proceeded to drive it by starting it with a screwdriver. Once home I procrastinated getting a new tumbler since I was able to start/stop the car with a screw driver. After a few days of this, I noticed the ignition was getting stuck again. I eventually figured out that I had to push a little latch inside in order to start the car. At that time, I concluded that the tumbler did the pushing for me when it is in place. So I hurried and got me a replacement (used) tumbler. (A buddy of mine has an identical car that he uses for parts.)

I used it for about 2 weeks without any problems and I was getting ready to order one from the dealer (since my buddy's was on loan) when I noticed the key was sticking again. Well, last week, it got stuck again. It took me about a week of trying (a few minutes here and there) to get it to turn THAT LAST time again. So now I have removed the tumbler again and am back to starting it with a screw driver. Actually most times I start it with a pair of needle nose pliers so as to not disturb the "latch" I referred to earlier.

At any rate, now I'm thinking the sticking is not due to a bad tumbler (both tumblers turn fine when outside) I'm starting to think I have some other issue going on. Perhaps the mechanism behind the tumbler is what is faulty. I've done more homework but I have yet to learn anything about this possibility.

Anybody here have any clues?

Anybody have detailed instructions on how to remove the cluster panel to get to the mechanism that starts the car. If I can take it apart maybe I can learn something.

jg

Reply to
jg
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Well, I don't have detailed instructions (yet), but I can tell you how to remove the instrument cluster. You pull it out. Seriously, its just held in by friction. To help me with this I made two "pullers" out of wire coat hanger with a short (1/2") hook on the end, and a handle fashioned about 3" away. (I read about the tool and technique here

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). Slide one in each side atabout the 80C mark on the Temp gauge, and the 60 mark on the Tach (formy cluster), then rotate the tool so that the hooks catch the sides ofthe instrument cluster. Then pull, it comes out easier than youthink. Once you get it pulled out then you need to remove everything off of the back. For mine, I found that the seat belt and glow plug lights came out the easiest, then the clock 12V line (spade connector), then the speedometer nut and line. Once you get those off you have a good bit more room, and there are a couple electrical connections for the tach and cruise (or something on top of the speedometer). The hardest part is disconnecting the oil pressure line in that tight space. Its a

10mm (I think) open end and unscrew it from the brass housing on the back of the cluster. One large connector (for dash lights, fuel, and temp, and other warning lights) and you're done. Once the instrument cluster is out of the way, then you will probably have some insulation to move to be able to get down to the switch from the top. Disclaimer: I don't know if it would be easier to get to the switch from the bottom by removing the lower kick panels or not, but for me its not.

Unfortunately, thats the most help I can offer. I haven't had the bad luck of my key not turning yet, but it may start soon. Quick question though... Did you rekey the tumblers to match your existing key? Or use your buddy's key for the tumbler you borrowed? If the former, could it just be a really worn key? Along those lines, who cuts keys for these things (other than a MB dealership)?

Ok, more questions than answers, sorry about that, but maybe we can learn together.

Reply to
DougS

I had an '89 260E whose got stuck in the ignition. Had to leave it where it was parked for 2 days until I could find a shop that would take a look. It was the tumbler, and it had to be ordered from TN after I verified my ownership with the local MBZ dealer.

Reply to
javelin343

You are better off by chaniging out the entire ignition lock. I did that in mine... I started out with a tumbler... then I find my ignition switch kinda doesn't work... and realized the pin key broke off on the ignition lock and then changed the whole damn thing.

Put a new tumbler in though...

Reply to
Tiger

Did you do the work yourself? How hard was it to remove the entire ignition lock? What all did you have to remove? Steps? Hints?

Thanx in advance.

jg

Reply to
jg

here

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Slide one in each side at> about the 80C mark on the Temp gauge, and the 60 mark on the Tach (for> my cluster), then rotate the tool so that the hooks catch the sides of> the instrument cluster. Then pull, it comes out easier than you> think.

I did not rekey my tumbler. I am using my buddy's key. I guess the possibility does exist that his tumbler is also bad but what are the odds?

jg

Reply to
jg

Yes, I did it myself. It is not too hard. Instrument cluster out... lower panel out... the trim plate around the ignition out... then turn to position one... loosen the collar nut by the lock and steering column... use a stiff wire like thick wire hanger and push that tab in... twist the assembly 90 degree and pull entire thing out.

To take of wire harness off the original ignition switch... key must be in position one.

Reply to
Tiger

(Snip)

Mine had been getting progressively worse but always came up with that one last turn. Until it didn't. At 9 AM. On the busiest narrow street in Manhattan where we blocked one lane of three and soon attracted the attentions of the Law. Called a tow truck and had the car deposited with an MB garage on the Upper East Side. Cost some $400. But I no longer worry about not being able to turn the key. Moral: if the ignition starts to get flakey, don't wait. Fix it. Or better, have a mechanic fix it.

Reply to
Gogarty

The moral of the story is spend $40 now or $400+ and towing fee later. your choice.

Reply to
Tiger

True. Not totally clueless, though. Towing was free.

Reply to
Gogarty

Not everyone get free towing.. and not everyone get $400 repair bill... most is around $600.

Reply to
Tiger

Really? $600? You mean I got a bargain in Manhattan, of all places?

Reply to
Gogarty

Guess so... I am suprised... who did your work there? I heard Manhattan MB is like $125 an hour.

Reply to
Tiger

Local shop on East 84th St. Hourly charge is $95.00

Reply to
Gogarty

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