New old guy here needing help. Just found and bought a really nice Williams Space Mission for a great price. When I got it home and started it up it had a couple of issues (besides needing to replace the worn out flippers, which I’ve ordered new ones). First the game and the scoring reels reset ok but the ball return kickout was struggling to kick ball over to the shooting lane. After 5 or 6 weak sounding attempts, it kicked it over and I played 2 games like that. The next time I hit the start/reset button, the Player 2 10,000 pt reel wouldn’t stop resetting and the Player 4 10 pt reel kept spinning as well. After doing some research on Pinside, I found that the switches for those reels were gapped too close and I adjusted them. That solved that. They both reset to Zero but then there were 2 relays in the back box that wouldn’t stop firing whenever I started a new game and the score motor ( I’m assuming) kept running and the ball return kickout hole stopped firing at all, even when manually engaging the switch. (The sound it made was the same as when the 2 score reels were trying to reset.) One last thing, I noticed after I adjusted the 2 score reel switches, I must have accidentally detached a doubled red wire that goes to a lug near the credit unit. I tried holding it on the lug as I started the game reset but nothing changed. I’m sure I need to solder it back first but right now the same problem exists with the 2 constantly firing relays, the running motor and no ball return kickout power. I’ll take a picture of the loose red wire in the back box when I get home from work. Thanks for any help because I am thrilled to own this machine.

Thanks for the reply, currieddog. I will definitely check the 2 switches you mentioned when I get off work. This bank of 5 relays side by side are not marked (like on my Aladdin’s Castle) but the 2 that keep firing are the 2 relays on the right end of a bank of 5 side by side relays that are at the center/left in the back box. If they were numbered 1-5 from left to right, it would #4 and #5. I should have taken pictures but was running late for work. I will for sure upload some later. Thanks again, I’ll update later today.

I’m going to check when I get home in a couple hours but I think that’s them. The one thing that’s strange (to me) is that the reels are all reset to zeros and no longer spinning but the relays are firing and the ball return kicker is dead. Before it was halfway trying to work. Lots to learn for this amateur but it’s fun. I’ll let you know what I find soon, and thanks.

You were dead on about which relays they are. The outhole relay switches looked like they’re ok (to me). Here’s what happens when you start a game. All the reels are good and reset to all zeros and are not spinning but the 2 relays in the back box keep firing and the score motor keeps running and won’t stop. That, along with the dead ball return kicker. I also included a picture of the detached double red wire that goes to the credit unit.
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Going to send a couple of videos of the issues in a minute

It’s not letting me upload the 2 short videos.

Gracias!

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Wondering what (if any) the correlation is between the videos and the dead ‘ball return kickout’, which was weakly running before.

Hi Rolf. The switches on the Bonus relay under playfield don’t move at all on power up or start of game. Thanks for weighing in. I’ll wait to see where to go next.

I just cleaned the switches that we specifically talked about. I did read page 7 and that’s definitely helpful. Going to go through the gapping of the said switches in a few minutes. It’s amazing that there were 2 totally mangled switches on the Game over Relay and it seems to function ok.

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So guys.... the index D. Is here? Sorry but I’m a total rookie just starting to learn schematics. And besides checking the score drum switches for a closed one that’s supposed to be open, what do you think is the next move? Thanks for your patience and help.

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Thanks a bunch HowardR. I’ll start there tomorrow. As green as I am at all this, I can’t help but feel myself learning valuable information during every step thanks to everyone on here. Exasperating fun.

Not yet Cheddar but I appreciate the tip. I’m putting it on the list now. I just got some 455 flasher bulbs for my Nitro Ground Shaker from Lodi CA. Pretty cool.

Will do. Thanks. Going to spend today on this.

Small update:
After absorbing all the advice from you guys and reading some of the literature that you all led me to. I started with the scoring reels and manually stepped up the player one reel by pushing the coil plunger a few times to observe the switches. I then manually stepped up the player 2 and 3 a few times. I then hit the power and started a game. This time the score motor didn’t keep running and the ball kicked to the shooting lane although it took the kicker a few times to kick it over. (When the score motor was continually running before, the ball return kickout was completely dead). I played a game and everything went like it should. I then hit the credit button to start another 1 player game and the player 1 score reel only reset to 00900. The ball kickout then took 5 tries to kick the ball over to the shooting lane and sounded a little weak (to me) in doing so. So..... that’s where I’m at. Maybe this sheds a little more light for you knowledgeable people. I’m reading and proceeding cautiously.

Thanks a bunch Rolf. I just posted something that happened when I manually stepped up the score reels. I will now slowly try to absorb your newest advice and proceed accordingly. I really appreciate all the help! I’ll update as soon as I can.

Getting crazier by the moment. Played another game and this time the spinning target didn’t move, the extra ball lights and thousand point spinner lights came on way prematurely. I only gently cleaned a few switches yesterday and that’s it. I fear I may have screwed something up much worse now. Also, it’s back to the score motor running nonstop on startup again.

Yes the swinging target in the middle. Good advice. Definitely not going to do anything new. I did this again... I manually step up the score reels a few times, the game will reset on startup like it’s supposed to and the score motor doesn’t keep running but some othe things are out of whack. The Spinning Target is not moving and bonus lights are coming on prematurely. Going to retrace my steps now carefully. Thanks

Get some sleep Rolf. Thanks for your help. Going to take me some time to learn but I’m determined. This machine is not going to let “me” sleep.

Dead on.

Hi Rolf.
I still have the original problem and have possibly created a couple of new ones. For reference sake, i’ll Start with what the machine was like when I brought it home and what I have tinkered with and what it is currently doing.

When I first started the game up the score reels began to reset and Player 1 and player 4 reels reset perfectly and stopped but the Player 2 and 3 reels kept spinning (Player 2 10,000 point reel and the Player 3 10 Point reel). After turning the power off and back on, they then reset to Zero and stopped and the ball return kicker kicked the ball to the shooting lane, although the kicker sounded weak and it took 4 kicks to get it done. I played a couple of games and everything on the playfield seem to work like they are supposed to, including the Swinging Target in the middle. Then I tried to play another game and when I hit the start button, the 2 score reels that I had problems with before, started doing the same thing as before. They kept spinning. I stopped and read where someone on another thread mentioned that the switches on those 2 reels might be gapped too close causing them to keep running. I probably shouldn’t have but I gently adjusted the 2 switches outward so there was more of a gap and after doing so those 2 reels reset to Zero on the next startup just like they should but that’s when the score motor kept running and the 2 relays (1-2 player reset and 3-4 player reset) kept pulsing nonstop. From there I gently cleaned some switches on the cabinet floor that were possibly involved. Such as the Outhole relay switches, a few score motor switches that were pointed out in a schematic above and on the bonus relay. That’s probably where I added more problems. After that I manually stepped up a couple of the score reels with the power off by pushing the plunger on the coils so I could observe how those switches operate. After doing that I started a game up and everything reset like it is supposed to and no more running score motor or backbox relays. But when I played a ball I noticed now that the Swinging Target in the middle wasn’t moving, the spinner on the left lit up prematurely as did the Extra Ball light at the top. These are the newest problems I’m afraid I created myself,possibly when I cleaned the switches. Also, when the game did reset properly, the ball return kickout to the shooting lane is still struggling to do its job and I checked for obstruction and there is none. That’s where everything stands right now. I can and will take pictures when I get home if that’s needed. And unfortunately Rolf, I haven’t been able to bring any of your well thought out advice to light due to my ineptitude and impatience. Let me know what you think, and thanks again for your help.

Awesome Rolf. That is great to know about what switch b does on the game over relay. I was hoping that the mangled switches were part of the problem. I’ll do what you said and update later. Thanks.

You nailed it Rolf! I cleaned and slightly adjusted the mangled A and B switches and the Swinging Target started working again. Not only that but the score reels reset to zero and the score motor stops running as it should as well as the 2 relays in the back. My only issues left now are with the Extra Ball and 1000 point Spinner light coming on way too early. And of course the weak ball return kicker. I’ve learned the Set-up relay goes to those 2 things. I’ll wait for more advice but I’m thrilled. I can’t thank you and Currieddog enough for all the valuable advice. I’ve learned a lot in a short time thanks to you 2 and the others in this thread. Thanks HowardR and Cheddar!

A pic of the beautiful patient.

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