What are the Outhole relay and the Bonus relay doing when this happens?

What happens when you hit the credit button on the game to start a new game?

Your running score motor when the ball drains problem could be explained by the Advance Unit not resetting. Here are the relevant bits of the schematic annotated for each of the steps described below:
Skylab Advance Unit (resized).jpg
I believe that the sequence should be:
1 - The ball drains and closes the Outhole switch.
2 - When the Outhole switch closes it fires the Bonus relay. Note that neither the Advance Unit nor the Ball Count unit are at zero so their switches (to the left of the Outhole switch) are closed.
3 - When the Bonus relay fires, a switch on the relay closes to send power to the Score Motor.
4 - The Score Motor starts turning because the switch on the Bonus relay is closed.
5 - When the Bonus relay fires, its holder switch closes and keeps the Bonus relay active, and the Score Motor running.

I think this is what you're seeing and why the Score Motor keeps turning. What you may be missing are the remaining steps:

6 - The Bonus relay stays active through its holder switch until a switch on the Advance Unit opens when the Advance Unit steps down to its zero position.
7 - When the Bonus relay is active, it closes a switch that allows the Advance Unit reset solenoid to fire and step the Advance Unit down to its zero position.
8 - A Make/Break switch on the Score Motor (which is turning) closes once each time the score motor turns 180 degrees to send a pulse to the Advance Unit reset solenoid through the Bonus relay switch (#7).
9 - The relevant Score Motor switch is a Make/Break switch at the top of the switch stack on the #6 score motor cam.

The Advance Unit is probably a large stepper under the playfield or on the bottom of the cabinet. I think it steps up one step at a time as bonuses are accumulated, and steps down one step at a time when the ball drains as bonuses are added to your score. Your Advance Unit seems to not be stepping down. This could be because it's mechanically bound up or because the circuitry driving it isn't working properly. Here are a few things to try:
- When the score motor is turning, manually push in the plunger to the Advance Unit reset solenoid and let it go to see if the stepper steps down. If it does step down, repeat until it reaches the zero position and see if the score motor stops turning.
- Carefully check that the Bonus relay switch (#7) and the Score Motor switch (#8 & #9) are working correctly.

And to answer a question in your video, hitting the left flipper button to light up the game is normal.

/Mark

Just watched your video. From the vid, it’s obvious that when the ball drains we are energising the outhole RE. This will start the score motor turning. When you remove the ball from the outhole the score motor finish its cycle then stops. This is all good.

Like MarkG’s post - What I noticed when the ball drained that you did not get any bonuses. If spacelab is completely lit, you should receive 24k bonuses, and you don’t. Have a look around the advance unit. Start by resetting and stepping it up manually till is operates freely. Check to see if the end of stroke Sw is correct and not on the wrong side of the arm that operates it. Take a few pic and up load here.
Also look closely to this M/B SW on the advance unit, marked with the red ring below. I think your issue is to do with the advance unit and/or bonus RE.

The advance unit looks after the lighting of "SpaceLab" and bonus scores ETC.

If you look at the schematic, and I know you have one. The Lock RE is what turns on the lights, E4 on the schematic. If you look below the coil there are a few SW’s that will energise the lock RE coil, one of them is the left flipper button. This is very common, so that is one of the Q sorted in your video.

Help (resized).jpg

Hi theoakade +
I pick the problem "middle of an neverending game". In short - You press the left flipper-button and the Lock-Relay pulls-in and stays endlessly pulling (this is good) --- not good is: The Game-Over-Relay MUST trip (and in Your pin the Game-Over-Relay does not trip).

You know a doorbell-push-button - You press the button and the doorbell rings - You let go on the button and the bell quits ringing. A simple relay with one coil mounted on the relay works like this.
You also know the Toggle-Switch on Your pin --- You toggle-on and take away Your hand --- switch stays toggled-on --- after a while You toggle other direction, take Your hand away --- and the switch stays toggled-off. The Game-Over-Relay in Your pin works like an toggle-switch - it has TWO coils mounted - such type of relay we call "Interlock-Type Relay" - look at the first JPG - the Game-Over-Relay in my "Shangri La". Williams usually has the Game-Over-Relay mounted near the transformer - near the player, in the bottom of the cabinet, righthand-side.

Danger - always toggle-off the pin AND UNPLUG the main power cord (do this unplugging). ONLY plug-in / toggle-on when You need electricity for playing, for doing tests --- then wear rubber gloves or use an wooden stick - NEVER touch solder-lugs / bare wires.

Toggle-off the pin, unplug the main power cord --- look for the Game-Over-Relay --- move one of the armatures - then move the other armature --- see it: You move and it stays --- You then move other direction and it stays. THEN TRIP the Game-Over-Relay means You move the armature NOT-HAVING the Nylon-Ladder mounted ("Yellow-arrow in the first JPG"). Then plug-in, toggle-on, press the left flipper-button --- the pin should NOT resume "in play". Then have credits on the Replay-Counter, press the Credit-Button - does the pin starts resetting ? If nothing happens: Wear rubber gloves or use an wooden stick - move the armature on the Coin-RELAY ( most likely also in the bottom of the cabinet) - does the pin shows some reaction ?

(((IF, if, if You want the old, wellknown situation: Move the Game-Over-Relay-LATCH-Armature and the pin should come into "in play". The LATCH-Armature is the one having the Nylon-Ladder mounted on the armature.))) We may talk (later) about the second JPG. Greetings Rolf

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