First up I readjusted the left outlane switch (again) and it seems to be fairly reliable now.
Yesterday's final-ball bonus switch adjustment seems to have stuck as well, so yay for that.
But today's big work was on the KS "advance unit" relay. It is a small stepper unit packed tightly in to the under-playfield relay bank.
|here it is removed from it's bracing. You can see how it has wires leading to a playfield plug. Those control the under-playfield lights. This alternates the lights in the right bagatelle lane, as well the 5 "advance" lights beneath the spinner.|
|side shot. There are 2 blag cogs, one that alternates on off (side lane lights that alternate) and one with 5 steps (awards bonus on the 5th)|
|This shot shows the white gear that marks each advancement, as well the 2 big switch stacks.|
I wasn't sure how to tighten things in there to prevent the cog from getting pulled down a bit, so instead resolved to clean the black gunk from between the gears. I used a q-tip and rubbing alcohol, but that was too blunt for this tiny thing, and ended up using a dental pick to scrape what I could out of there.
I powered it back on and this seems to have done the trick! Right lane lights were alternating, bonus were scoring on the 5th spin! Success!
Oh... wait. The advance lights are all off. OK, that's a problem.
In the top pic you can see the stepper plate, which alternates around making contact with the heads. With my chopstick and pressing down on the center metal, the lights would come on, meaning the heads were not making good contact.
I followed the great guide to cleaning stepper units on pinrepair: cleaned with rubbing alcohol, sanded the contacts with 400-grit sandpaper, then used contact grease. The only thing I didn't do was disassemble the mechanism first, because it's oh so tiny and delicate. But in one position I could easily to 70% of it, then step the unit, do the remaining 30.
With that cleaned, it was making contact fine again!