Pat Hand is a 1975 Williams EM game. It belongs to a friend and I took it on as a learning project to get it working for him. I have some limited experience on EM machines working for a year once a week with a great mechanic that serviced EM machines for a pinball museum in Baltimore. Unfortunately the museum closed in 2012. I bought 4 EM machines from the museum, put them in storage in my garage, and focused instead on my 5 electronic games.
Owner says the game did play at one time, but it stopped working and got shoved off in a corner of his garage acquiring dust and paint/spackle splatters. I brought the game over to my garage, cleaned it up, replaced the incorrect power cord, replaced an obviously burned up Lock Relay coil, and cleaned up the gunked up stepper mechanisms. The game was actually surprisingly clean on the inside given it's poor external condition. Also surprisingly after we drilled out the back box lock because the owner did not have a key for it we found taped to the back box cover a folder with all of the original documentation that Williams packaged with the machine when they shipped it. Therefore I have the original manual and schematic for the game in hand.
I confirmed that the fuses were correct and working. Then I powered up the game and it came up playing. There are some play field switch issues that I will get to after I finish cleaning up the play field. I did have to replace the sling shot kicker arm. The top portion of it had broken off and what was left of it would have directly contacted the ball below the rubber ring, not good. Someone must have recognized that risk and disabled the kicker switches. Amazingly Steve Young at Pinball Resource had the kicker arm in stock so I was able to fully repair the kicker, a real feel good.
Now for my problem that I could use help with. On reset the scoring motor runs a variable number of cycles beyond the point when the 16 scoring reels have reached zero. Most times it one, maybe two or three cycles. I could live with that. But sometimes it seems like it is never going to stop cycling. A couple of times it did it for so long that I powered the game down and re-initiated the process.
When the cycling is occurring the the bonus unit steps down to zero and then up to one, the bonus relay pulls in and drops out, and the two scoring reel reset relays pull in and drop out. Finally the reset relay, which is pulled in solidly during the cycling, drops out and the reset cycle completes properly. It appears that the index reel of the scoring motor mechanism drives switches that should cause the bonus relay and the reset relay to drop out when the 16 scoring reels are at zero. I cleaned up the contacts of all the index reel switches and for good measure also cleaned all the reset relay driven switch contacts. That initially appeared to solve the problem. But after a day or two of occasional playing I noticed that the problem is back. I am thinking that somewhere in the game there are switch contacts that are not making good contact or not fully opening that are causing the machine to think that the scoring reels are not at zero even though they are and therefore keeps the reset cycle going. Does anyone have any ideas?