Have a midway white lightning rifle project that is just about complete. Everything on game appears to work correctly but I noticed at times when a game is started the credit wheel will decrement more than 1. All other score wheels and timer reset correctly. Sometimes it decrements only 1 while other times it may decrement 2 or 3 times. When this happens I do see the latch relay on the credit wheel cycle on and off letting the wheel spin. Adding credits from the coin door works correctly. Based on the plug selection in back it will add 1,2 or 3 credits per coin and I verified all setting work correctly.
Been looking over the schematic but have not been able to track it down yet. Any suggestions would be great.

Travel too far. Start game and credit reel will decrement more than 1 credit. I will attempt to attach links to videos

Credits being added. correct

https://photos.app.goo.gl/FSpK7CBM2651qVEx7

Game start showing 1 credit decrement. correct

https://photos.app.goo.gl/ktb8cWu5gUwu9Lhf9

Game start showing multiple decrements

https://photos.app.goo.gl/F14NbzZytD2FUnr2A

I will check the wipers again. I had to disassemble them "VERY CAREFULLY" to clean all the wipers and discs. Cleaned wipers and disc to remove all the old grease which was like glue, got the oxidation removed and put a light coat of super lube on them. Pretty confident I put them back together same way they came apart. The videos were show in order (add credits, good game start, bad start with multiple credits decrementing) It seemed to me the scores reels did reset all the way but will have a look. Also noticed when credits are added the timer wheel moves as well which I would think should not happen.
So could be something in the score wheel set up is still not right. Is there any good info or diagrams on the Midway score system? I have not found anything only warnings about if not broke don't fix it.

Found White Lightning service manual so have diagrams of score wheels and timing unit so can double check assemble if needed. also have schematic

B
When I took score reel/timer apart I did not lube anything and left the leather clutches as is. I only cleaned the disc and wiper fingers of old grease and gunk and once cleaned applied small amount of super lube to those. Its not clear, and I was not sure what to clean or lube in the clutch reels and they seemed to be working ok. Thanks for the neatsfoot oil suggestion for the leather washers. What did you clean those with? what other surfaces in that set up should be lubricated? I did clean and lube bearing at each end where shaft goes thru end plates. Not sure at this point I want to take system back out of game and apart unless necessary. I thought when I bench tested it all before going back into box it was fine but clearly did not notice credit reel issue.

Not sure what "top this score" mech looks like or where it would be. I do not have light sockets for star, shoot again, credit or 40. those are just holes in the metal plate. I did start a game and manually hit the credit relay on back door and credit reel did increase. I also played a game that started with top this score at 500 and when I scored over 500 a credit was added.

I did notice some arcing in a couple relays on back door which I did clean?? So this time I took each one apart and made sure they were cleaned (some had pits on the seats) and adjusted to ensure good contact in both on and off states. (included pics) After doing this my credit decrement issues is almost gone. I say almost as I only saw it once in about 6 game starts so more play time needed.
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One more pic to keep you motivated.

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