Ziptide February 2020

Feb. 3, 2020

Mystery Lock Identified

A subscriber sent us a picture of a lock he was trying to service. The locksmith was trying to change the key combination but could not determine any way to remove the unit from the door. Our resident electronics expert, Tim O’Leary, identified the lock as a Schlage KC9111 King Cobra model, which has been discontinued for some time.

This lock has two hidden retainer screws. To access the bottom retainer, an operating key must be turned counterclockwise in the cylinder. This releases access to a screw below the cylinder. After loosening the screw, a cover plate can be moved downward to access the bottom retainer screw. A hole near the top of the housing can be used to access the top retainer screw. You must use a ball-type hex wrench, because the access hole is purposely off-center.

A King Cobra service manual is still available on the internet and proved very helpful in solving this mystery.

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