Quoted from evh347:
I just want to say 'thank you' for all the great stuff in this thread. This particular conversation was very helpful as I was having the same issue with my Buzz gofer acting as though it was hit, falling after getting raised. I did order Cliffy latches and the Bay Area Amusement residual plates as backups. My latches are still functioning fine and my machine actually did have the residual plates installed. I pulled the gofers apart so many times, I can now get them out and back installed in just about 15 minutes. I thought maybe the coils were bad, but everything I've read about coils is that they are usually the last thing in the machine to fail over everything else. I alcohol wiped the optical switches and the optics on the gofer.
The only really noticeable defect was the coil sleeves. The coil sleeves inside both the coils that raise the gofer and the one that fires to lower the gofer were grimed up with carbon residue. The coil sleeve inside the coil that lowers the gofer seemed to have a little resistance compared to the coil the lowers Bud. I tried wiping down the coil sleeves and that seemed to help, so I straight up replaced them.
So far in the gofer tests and a few games, Buzz is staying up and behaving more normally when he 'talks'.
I really appreciate this thread and all the great advice from the community. Thanks!
Well, I made a discovery that might help people with gofers that don't behave correctly. I replaced most of my parts on Buzz like DangerTerror did. I installed new springs, up/down coil, checked the roll pins, coil sleeves, checked shafts, ramp, lift coil bracket assembly, installed Cliffy catch plates, installed Bay Area Amusement residual plates, etc...
I still was having an issue with Buzz dropping as soon as I raised him. It would fail in test and gameplay. During gameplay, the gofer wasn't jiggling normally while 'talking' and instead exhibited big movements.
This problem all started when at one point a month ago the gofer popped up and got stuck halfway up/down in the playfield during gameplay during one of its animations.
When I investigated inside, I found the nut (#25) that fastens onto the machine screw (#24) had fallen off into the bottom of the cabinet. I re-secured the nut, but I may have over-tightened it. My thinking was to tighten it so it wouldn't fall off again. Surprisingly, it seems however much I tighten this nut, its really just a matter of fifty plays and the nut has worked itself off the machine screw again.
At any rate, I re-secured the nut but left it a little looser than before...and ta dah...it works. Just crazy that these gofers seem to rely on such precise installation of seemingly insignificant parts to work properly.