optical drive

I have a MacBook Pro 15" 6,2 recently upgraded to 10.11.6. The optical drive won't accept a disk. I tried all the suggestions I found on the internet, but nothing worked so I finally took the computer apart to examine the drive. There was no disk in the drive. There are three levers that control the insertion of a disk. Mine seem to be out of phase. That is, one lever sits in the wrong position and only allows me to stick the disk in about an inch. If I attach a battery to the motor that moves the levers, I can move the troublesome lever to its proper position to allow insertion of a disk , but the other two levers then move to block insertion.