Locksmithing 101

[bill]

My trunk lock has never worked with the key that came with my coupe, so after finding the lock code I ordered a new key. The new key didn't work the lock either. So I decided to take the lock apart and see what was going on. Turns out the PO had already been there and monkeyed around with the lock and lost some tumblers, springs, etc., precluding the use of ANY key. So my only choice was to work with what I had. I re-assembled everything and ended up being able to use only one tumbler with my new key, but I can now lock my trunk.
For those coupe owners so inclined, taking the lock mechanism apart is not difficult, but the tumblers, cups, and springs are very small. If you can fix a watch or have experience as an HO train modeler, this is a piece of cake. The diagram herein shows how everything fits together.
If you have a key that doesn't work in your lock and you want to re-arrange the tumblers to get a key to fit, let me know by PM and I can give you some pointers to keep in mind.

 

[Bmachine]

Yes, this is a good fun project you can do on the kitchen table without risking unnecessary domestic verbal violence.

IIRC, on my previous coupe I reworked my tumblers so all locks and ignition worked with the same key.

 

[sfdon]

Very nice post. Thank you!
Think I will practice on a spare first though

 

[HB Chris]

I took one apart once and had springs and pins everywhere. I use Balport Lock in Newport Beach, they can cut dimple keys.

 

[MyFemurHurts]

I need to do this at some point. My dimple keys work in the doors and trunk, but the ignition is a smaller normal cut key. I should have done this when I replaced the ignition switch, but I was in a hurry to get the car on the road for an event. :evil:

 

[CSteve]

My euro coupe, Italian delivery, came from the PO with what believe was a 320i key and ignition. I only recently found an original key and ignition switch and had them installed. Then a local dealer, using photos of the single new key and key number, made two additional keys. Cost for the keys, $95 for both.

Well worth it.

 

[bavbob]

When I do this, I grab a nice size open top box from Costco and do all the work inside the box so when stuff goes flying, its contained.

 

[Arde]

When I do this, I grab a nice size open top box from Costco and do all the work inside the box so when stuff goes flying, its contained.

Most tech workers here in Silicon Valley also work inside open top boxes called cubicles.
Many times however when **** goes flying, it is not contained...