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If you've ever had to replace your ignition lock cylinder on a late model Bronco, you may have ended up with two different sets of keys.
What this write up is for is to show you how to change the tumblers from your old ignition lock cylinder, into your new one, so that your old key will still work. This keeps you from having separate keys for doors, and ignition.
I used a cheap ignition lock cylinder from O'reilly's so your experience may vary slightly.
You will need:
Old lock cylinder and key
New lock cylinder and key
A very small flat-head screwdriver
Patience and steady hands.
The pictures are very low quality, the flash wasn't working.
Take your time, if you lose the order of your tumblers you'll spend alot of time trying to figure the correct order out.
If you lose any of the OLD tumblers from the old lock cylinder, you're done.
I decided to do the writeup after I had finished, so this is once lock cylinder taken apart and put back together, sorry.
Do this one cylinder at a time, and keep all parts separated.
Insert the key and remove the center piece from the solid outer ring (you may have to turn the key)
Remove this ring from the center piece
Using your small screwdriver, remove the tumbler cover plate.
It's hard to see, but underneath is six small springs, using your screwdriver, remove them one at a time and store them safely.
Now you can see the tumblers inside their individual grooves.
When your key is inserted, and all the tumblers match up, this "key" sticks out, it's easiest to remove the tumblers if you take this out.
Lift the two retaining bars , remove springs, and key.
Using your small screwdriver, SLOWLY and CAREFULLY remove one tumbler at a time, starting from the front towards the back, and KEEP THEM IN ORDER!
On the left you can see all of the tumblers placed in order
Complete all the above steps on the new ignition lock cylinder, however since you will be using the tumblers from the old cylinder, you wont need to worry about the order of the tumblers.
Once you have done that, take the new lock cylinder center, and start placing the OLD cylinder's tumblers into it, one at a time, in the same order that they came out of the old cylinder.
It's hard to see in the pic, but now you will put each of the springs in their grooves as well.
Followed by replacing the cover plate (also hard to see)
Now you will want to put the rectangular "key" back in place, followed by the springs, and retaining bars
Slide the ring back in place:
Slide the center into the solid outer ring, being careful not to damage the black plastic piece, or the copper conductor on it.
Test the new cylinder for function and put back into your steering column. If you're patient, and take your time, it will save you paying a locksmith, and save you another key on your "already too crowded keyring."
I apologize again for the quality of the pictures.