I recently acquired a TZ, my first purchase of a pinball, and I’ve been having a blast fixing stuff on it. My family and I have been having a blast playing it too.

I need to tackle the clock at some point, the minute hand optos aren’t registering. But while working on something else, I had the pf pulled forward and resting on the handles, and turned on power. The clock passed the self test! Apparently just from sitting at a different angle, the optos were registering the minute hand.

I also have an issue where sometimes during play I’ll hear a solenoid fire under the pf, when there’s not a ball under there. Always twice, separated by a second or two: “thump” ... “thump”. I’m pretty sure it’s the solenoid that kicks the ball up out of the slot machine. And sometimes the diverter on the wire ramp will flip for no apparent reason (even if the ball was nowhere near the ramp). Any troubleshooting tips?

Turns out I've already got the Ingo board in there. I took the front plastic off and found that the arms axle has a lot of play front to back. Maybe 1/8" or so. Is that normal? I wasn't up for tearing it down more, so instead I wiggled the optos "out" a little way so they're closer to the arm. After that, all the minutes register properly with the clock in the normal position.

And for the first time since I've had the machine, no credit dot!

Good suggestion, I'll try applying some percussive motivation while in edge test to see if any switches or optos register.

Another thing that's been happening is occasional airballs when the ball hits the target right next to the slot machine scoop. Sometimes really bad airballs, like off the glass, over the sling and landing in the left outlane. I already tried bending the target forward but that didn't help. Do I need to replace the foam stuff behind it?