I can't speak for the Elmo, but the Kodak has a plastic link attached to the solenoid plunger that has a way of becoming brittle and breaking. This, along with the motor-mechanism belt is the first thing I would look for.
The mechanism comes out in one piece along with the cage that holds the lens. Further disassembly is fairly straight forward, as I recall.
It appears that micro-tools has a decent line of parts. I've seen service manuals somewhere on the net; maybe they have them too.