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Hi there,

This is long so if you feel its a tl,dr then in a nutshell this can be done quite easily - once the tumbler has been released!

As some of you may also have experienced, my ignition tumbler got stuck. It happened maybe 6 months back and I left it over winter but now with summer here I figured I better get it sorted. I had actually forgotten about it and pulled the car out of the garage for a wash and realised while I was washing it the ignition was fine again. Anyhow, long story short, this was short lived as when it came to put car back in garage it was jammed... properly jammed.

I tried for maybe 3 hours all in on that day to free up the key and no luck (tried both keys). Jiggling this and that putting a vibrating massager on the key while trying to free it all up - no luck. I left it over night and researched my options. None looked great.

I then tackled it again in the morning after getting a better understanding of how the tumblers are arranged on my key setup. I got one of the narrow keys.

So my method was to jiggle the key in this direction ^ , up and down, if the key handle was aligned like this | . Jiggling side to side will not help at all. The key should also be pushed all the way in and then backed out a mm or 2 - you can feel the pins come to rest at a certain point. I think the vibrating method is very awkward to work and will help with stuck tumbler pins rather than worn out ones. A point to note here even though keys can look worn its likely to be way less worn than the tumbler pins made of brass. A good check is to see how your keys work in ALL the other locks.

The thing with this tumbler setup is by having pins 180 degrees opposed by jiggling the key as described you may clear one pin one side but then the opposite pin extends further ... but wiggling in a see-saw motion seems to be the best method with light torque pressure. If you apply hard or even medium torque pressure the pins will remain wedged in place. The pins also have very small 'teeth' that grab quite easily - so keep this in mind.

Cutting to the chase ... don't give up jiggling. I got the key freed up (I had to do this twice as I accidentally rotated the key to off while trying to insert the wire pin 🤬 - the second time went much faster). and got it to ignition 1 and was able to insert 1.5-1.75 mm wire in the hole to release the locking pin for the metal shroud so it could be turned out. Managed to release that although not without scratching the paint up a bit :rolleyes:.

The pins were quite worn ... 3-4 of then sticking out about 1mm easily snagging on the tumbler barrel which had also developed some burrs in the pin ways. I think forcing the key too hard is not a good idea as this will enlarge these burrs and make releasing the tumbler worse. They also seemed to be the pins at the front and back of the barrel, perhaps that's why the see-saw action worked best to release the pins.

Anyhow I proceeded to rebuild the tumbler. This is well described here


I went through these steps in the link and managed to sort it out just fine. There was a fair amount of debris in the lock but the main issue was worn pins AND burrs on the housing from pin teeth contact / pressure when it caught. The pins have numbers - mine ranged from 1-5, and there are 10. Ideally replacement pins would be the best solution but I doubt they are available (I did not check). One caveat to the process described is I think you most definitely need to remove the pins. There is allot of crud in the springs themselves that I don't think solvent will get to and you need to fine tune the pins to get them to move freely after grinding. Obviously make careful note which pin goes where.

This process worked fine although you need to spend allot of time deburring the pins after the tumbler has been filed/ground down as well as the tumbler's pin housing slots to make sure there is no binding / sticking of the of pins and the key inserts freely. Clean the whole lot in isopropyl, and check each pin for freedom of movement.

I then sanded down the visible part of the scored black metal shroud, after some scratching during the removal process, to bare metal and polished it up as I was not wanting to paint it up - I expect I would never get as good (or thick) a paint job as OEM and it would chip over time requiring another process of re-re. Dunno what this is painted with but damn it is hard as a rock.

In the end it came up a treat ... I'll post a pic soon as I just got the car back together and back in the garage, still with the original set of keys and the tumbler is working perfectly. I would highly recommend restoring the tumbler rather than replacing with a new one especially if your car still has the original key set and its also a decent cost saving. My replacement barrel at SLshop is £175.

I lubricated the pins with 3 in 1 oil and it feels really slick. I know a wet lube is not the recommendation, but my key maybe finds itself in the ignition a handful of times a year (sadly) - and the key does not get a chance to pick up crud - I think it will be just fine. Its mainly a wet oiled key that brings debris into a lock, than a wet lock attracting crud. I just make sure my key is always clean before used.

Good luck with your job!
 
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