Gottlieb Strange World EM Pinball Repair

I recently got a Gottlieb Strange World EM pinball machine brought to me from a customer. The owner stated the score motor would just spin when the machine was on.  I brought the machine to my shop and started going through it. If you are curious to what it takes to get one of these EM pinball machines back up and running then continue reading :).

The Backbox

I did not know the condition of the machine so went right to the back box and tried advancing the ball count unit. The unit would not manually advance when I pulled in the plunger nor reset when I pulled the other plunger. I removed one screw holding the ball count unit and got a good idea of why it was not moving smoothly.

I then tried manually adjusting the credit unit along with the score reels and none would advance smoothly.

I spent a while taking apart all the stepper units along with the score reels. When I had them apart, I cleaned all contacts and rivets, applied lube on the rivets, and adjusted contacts.  I found and replaced one broken EOS switch on a score reel. I reassembled and manually tested everything. All of the units and score reels were advancing smoothly.

After cleaning the units and reels, I tried to pull in the L, M, and N relays to see if the score reels would advance. They didn’t advance. I took all three relays apart, cleaned, and adjusted switches. Once this was done all score reels and carryovers were correct.

Initial Power to Game

With the back box work was done, I went ahead and checked fuses for any that were blown. I didn’t not find any and plugged in the game. The scores would not reset.  The relays would lock on and not advance. I was able to trace this problem to motor 1A switch. It was “popped” out of the track and was not actuating. Adjusting the switch allowed the scores to reset to zero with the ball kicked out to the shooter lane.

However, the ball kicked out and fired the coil 5 times. This was also true when the ball was sent to the hole kicker. I traced this problem to motor 4C switch.  The switch end up being bent and would not close.   

The final issue before moving to the playfield was the game would not end. I would drain the fifth ball and the game would continue playing.  This was my fault as I reinstalled the cam incorrectly on the ball count unit. I quick glance showed that this was the case and six position ball count switch was never opening.

The Playfield

The first thing I did was check resistance on the coils and look for anything that might have been shorted. Found that the blue pop bumper had a burnt coil. The blue pop bumper worked after replacing the coil, adjusting switches, and cleaning the relay.  Double checked the other pop bumpers and adjusted a couple switches.

When playing a game, I noticed the lights were not resetting and blew the fuse. I reached for my circuit breakers and installed one. On closer inspection, I could see the series sequence bank was not resetting at the start of a new game. This was fairly easy to trace down to motor 2C switch. I cleaned and adjusted all the switches on the 2C stack. This fixed the light problems, but noticed the 5,000 when lit lights were not coming on when they should. I went through and cleaned and adjusted all the relays on the series relay bank. This allowed all the lights to work correctly. The circuit breaker did’t trip any more.

The last thing that I did was replace the power cord. The current one had a missing ground plug and the hot and neutral were installed backwards.

Conclusion

This was a fun game to work on as there are not too many Strange Worlds out there. Thanks for the help on Em Pinball on Facebook!

I liked the scoring sequence of getting the 5,000 point to light. You would have to get the white 1, yellow 1, and green 1 before the light would lit. Once you did this for numbers 1-4, the special would light.

Mmm…I wonder if Gottlieb sent a message to the makers of Monster Inc?