I recently got a Gottlieb Pro Football pinball machine in the shop to repair. This is a similar layout to the Gottlieb Home Run game that I repaired a while back.

The owner stated that sometimes it would start up, sometimes it would end a game earlier, and other times wouldn’t work at all. He wanted to have the game serviced and then would deliver it to his son.

Initial Checks for Repair

The first thing I noticed when I was going through my initial checks were the scores reels were not resetting. I also noticed that the Ball Count unit was gummed up. I was able to start a game by engaging the start relay along with tripping the AB Relay. These steps allowed the score reels to reset and to play a game. Once the game started, I noticed that three out of the four 1-point targets were not scoring along with the pop bumpers not activating.

Troublesome AB Relay

Fixes to Repair the Game

By hitting the Replay Button the Start Relay engaged and the Score Motor turned. This is exactly what it should do along with tripping the AB Relay. However, the AB relay was not tripping to reset the score reels. After cleaning and adjusting switches, I found it was a mechanical issue on the relay. After cleaning and adjusting this relay and the game was consistently restarting along with the ability to play a full game.

AB Relay circuit

Next problem was the 1-point targets. Since once target was working, I started my search there. This led to finding a loose wire. Re-soldering this wire brought scoring back to these targets. For the pop bumper problem, connecting the Jones plug into the the head of the machine resolved the issue.

The last problem that I found was the game was not awarding credits for meeting the high game score or score values on the apron. The game did award a credit for a match, so I started on the J Relay and was able to find a broken wire in the circuit. Re-soldering the wire back fixed this problem.

Finally, the game got a well-deserved vacuuming, playfield cleaning/waxing, along with new rubbers. I replaced a few light bulbs and the game was back up and running.

Light check before re-assembly

Gottlieb Pro Football Repair Video

Here’s a video of my troubleshooting process along with some trial-and-error that I encountered along the way. It just shows that sometimes you have to work and try different problem solving techniques to get the game repaired. I will say working on the Gottlieb Pro Football pinball machine, gave me an itch for repairing these machines and documenting my efforts. I have created a course for anyone wanting to learn more about repairing EM pinballs.

If you enjoy reading these blog post or watching the videos, please let me know by subscribing, liking, commenting, or sending an email. It’s been a while since I have created content and would appreciate ANY feedback!

More tips and tricks in the video!

*Thanks to Fun with Pinball for the use of emSim (schematic drawing tool and simulator).

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