Right up front I should say that I don't have experience with pinball machines, but I have been reading some things about EM machines, and I have a fair amount of electrical knowledge (don't let the user name fool you).

I have a Gottlieb Scuba machine that I'm trying to get working. It seems like it's close to functioning, it just never seems to start a game. Both the playfield and backglass light up when I plug it in. When I press the start button, both the scoring motor and the player unit go through a cycle that lasts about five seconds. There is a youtube video titled "Gottlieb pinball reset sequence animation", and what's happening looks very much like what that video shows (can't link to it with so few posts on this forum.) During this time, the ball in play display cycles through its range of 1 through 5, and the score reels will reset to zero if I had manually set them to something other than zero. It should be noted that the game over light stays on continuously while all of this is going on.

But after this cycle ends, I'm basically back to where I started. No ball in play numbers are lit up, just game over. The flippers don't respond, and neither do any of the bumpers. If I manually trip the far right coin switch, the scoring motor seems to go through a shorter cycle, maybe only 1/3 of a turn. Three credits also get added to the credit wheel, but the machine still doesn't act like a game is in progress. If I push the start button again, it just goes through the same cycle I described before, and the credit display decreases by one.

I thought maybe the game was in the tilt mode, but if manually trip the tilt switch, I can definitely see the tilt relay energize, and all the playfield lights shut off (this persists even if I unplug the machine, until I hit the start button again and the machine goes through the whole cycle again.)

The only other odd thing I noticed is that if I trip the far left coin switch (there isn't even a coin slot installed here) the machine seems to go through the same cycle as if I pressed the start button. None of the coin switches appear to be stuck on. All relays along the right side of the lower panel seem to move freely.

Any ideas? It just never seems to start a game. I do have the schematic for this machine, so that's good.

Thanks.

I have not had a ball in the outhole for a lot of my testing since I have been swinging the playfield up and down a lot to get into the machine. But I did put one in the outhole and ran it through the sequence again... Doesn't seem to make any difference. It does appear to be closing the outhole switch.

I even tried manually pushing the ball from the outhole back into the shooter lane after I pressed the start button, just to rule out a faulty solenoid that launches the ball into the shooter lane... No difference. And it does appear that the switch between the outhole and the shooter lane is tripping correctly.

I don't see that this machine has an outhole relay per the schematic, unless they call it something different, which is totally possible. Thanks for the help.

As I remember from playing around with the machine a little bit last night, I think the game over relay energizes as soon as the reset sequence completes. So, I guess it's logical that this would be preventing the game from starting up. I'm not 100% sure on that though. I'm not at home with the machine right now.

I think I'm going to start by running over all of the contacts in the relay banks with a small file to make sure everything is getting a good connection. There's got to be a corroded contact somewhere because nothing looks physically damaged or bent up inside the machine.

The game over relay is definitely energizing as soon as the reset sequence is complete.

Anyway, I took a small file and cleaned just about every contact there is on the lower panel. The only things I saw glaringly wrong were a contact on the sequence bank relay that should have been normally closed but was bent open, and a contact on the 3rd chute relay that was a normally closed contact, but it didn't actually open when the relay moved. I corrected both of those.

I did manage to get one good play out of the machine though. Just to see what would happen, I ran down the credit wheel to 0, and reset the game again, and suddenly the game over relay stayed reset. There were no balls in play displayed on the machine, and no game over light, and when I put a ball in the outhole, it got pushed over into the shooter lane.

The game seemed to play normally at that point. I had control over the flippers, and it even kept score on the player 1 reel, but as soon as the ball drained, it went back to a steady game over and no more response when I tried to play the game. I only scored 12 points.

The game over relay is back to energizing constantly. So, I guess I need to figure out why this is. Oddly though, now I seem to intermittently have the ball play display showing ball 1 in play. Game over is illuminated at the same time as this.

It seems like the bounce switch may not have been making good contact. I was a little suspect of it before since it seemed like it was just barely making contact, so I bent it a little so it would hold contact better. I should also say that I was not previously using the on/off switch the way I should have been most of the time since it is hard to get to where I am working on the machine. I had been just unplugging it and plugging it back in. It seems like there is a difference between that and using the switch however.

Anyway, it is a whole lot more functional now than it has ever been. It seems to run through a game properly. However, the score seems to rack up way too quickly. It seems like ten points register more like 110. 50 points registers as even more. The credits remaining also seems to increase rather than decrease, but now that I think about it, it may just be bonus credits because the game thinks I'm scoring so damn well.

Alright, well, it looks like the scoring is only messed up for player 1. Player 2 seems to work properly. When I increment player 1's score by ten, I notice that the next higher number place seems to come along for the ride and start rotating before the next lower number place rolls over from 9 to 0. So, for instance, the score will go from 0 to 10, but then instead of increasing to 20, it will show 120. Then just hitting another 10 takes it to 230, 340, 450, 560, 670, then the hundreds place takes the thousands place along with it, so I get to 1780, 2890, 3900.

Obviously I think something is happening with the player 1 score reels, but I have already taken a file to the contacts that register when each number is at 9 or 0. I have also cleaned some of the circuit boards that the decagon wheels rotate next to.

What else could be wrong with my scoring reels? They do seem like someone has lubricated them in the past. Would cleaning this out help my issue? (Obviously at some point I will clean them, I'm just wondering what would cause this.)

Thanks.

I would have thought the same thing, but I cleaned all of those switches, and they seem ok. It's also odd how the numbers carry over at the same spot each time, and they continue carrying over for the rest of the rotation of the number until it actually rolls over to zero again.

It's got to be something with the score reels though, considering that player 2 seems to work fine.

I found that the single contacts that are supposed to close when the tens spot reaches 9 were spread too far apart and weren't ever closing. Same with the hundreds spot, thanks. The only other real issue I see is that the machine always seems to start a new game, even when the credits reel shows 0 credits left.

Sorry, I was talking about two separate issues there. The contacts I found spread apart were on the scoring reels. But I did check the credit reel, and sure enough someone actually re-soldered a wire so that the 0 position switch was considered to be closed all the time. I actually don't want this machine to free play as the eventual goal is to put it in service for people to use. But, it doesn't look like it does now. The adjustments for how many plays per coin are still kind of a mystery to me though.