Hi mrbanjo
GREAT - You mention "when the fault is happening - then the Score-Motor does Extra-Turns".
So we can put away the JPG in post-4 as the "stuff in the JPG" works correct - the fault is "WHAT makes the Score-Motor do some faulty Extra-Turns --- WHY does the Outhole-Relay faulty pulls-in several times or: Why does the Outhole-Relay not quit pulling after that one, needed turn ?".
In another topic I showed in its post-11, https://pinside.com/pinball/forum/topic/captain-fantastic-need-help-with-startup#post-3548454 a JPG - I show it here again.
Please look at the JPG in https://pinside.com/pinball/forum/topic/captain-fantastic-need-help-with-startup#post-3548454 --- ONLY have a look and see in the upper left corner an ordinary Edison-type-Bedroom-lamp - I will come to "Edison-type-lamp" in my writing in here.
The Capt. Fantastic has a feature I do not really like - it makes the pin more complicated. The feature is "Every new ball given starts with ONE Bonus given --- The Bonus-Ladder to be on Position ONE (Bonus lighted)".
The Numbers "1,2,3,4,5,6" are for "starting a new game - resetting". When playing and loosen a ball the "11 to 20, A to D" stuff happens. You loose a ball - You do have some bonus on the Bonus-Counter --- there is connection (downwards in the JPG) "12 to 13", so "11,12,13,14,15,16" the Bonus-Score-Relay pulls-in and stays pulling through "4 and 5" - and makes the Bonus-Ladder counted down.
The Bonus-Unit counted down finally reaches Position-Zero - this "opens '5' " and let the Bonus-Score-Relay quit pulling which makes "Switch 6,18" close. Also the Bonus-Unit reaching Position-Zero makes the "12, 17 switch" move - so "through the green wiring" the Outhole-Relay (20,B) starts pulling. The Outhole-Relay closes its Self-Hold-Switch "C" and stays pulling until the "D" opens this Self-Hold-Circuitry of Outhole-Relay.
So on Your problem the question is: SMSF or INITF
SMSF - Does "rosa, pink 'D' the Score-Motor-Switch 8C" sometimes not open --- keeping the Outhole-Relay being PULLING nonstop (and the Outhole-Relay pulling asks for another Score-Motor-Turn) ?
INITF - Stays "Switch 12,17" faulty in "position-green" and at the same time the "switch 6,18" is faulty closed --- means: Does the Outhole-Relay nicely let go - BUT gets FAULTY feeded (through green A, B) again and again and again ? (Initial-Feeding electricity)
You may investigate in these "Score-Motor-Switch-8C - truely opening ???", "Make-and-Brake-Zero-Position-Switch on Bonus-Unit", "Switch on Bonus-Score-Relay".
Another way is / would be: "Edison-type-lamp". Bally has 50VAC in the pins - I believe / I guess (want to try ?) an ordinary cheap bedroom-light of 110VAC can be used as a "Test-Light".
Connect "one Side/Wire of Test-Light" with "one Side/Solder-Lug of Coil on Outhole-Relay".
Connect "other Side/Wire of Test-Light" with "other Side/Solder-Lug of Coil on Outhole-Relay".
With this setup the Bedroom-Light-Test-Light lights-up and stays lit when the Coil of the Relay is feeded with current.
Have the Bedroom-Test-Light so You can watch it - is there a little "flicker means fault-INITF" - or does the Bedroom-Test-Light ABSOLUTELY stay lit (no flicker) means fault-SMSF ? Greetings Rolf
0Captn-Fantastic-Work-05 (resized).jpg