Only during multiball: a drained ball stays in the outhole and is not kicked over to the trough, while the trough keeps trying to put more balls into play. In single-ball play drains register normally, and all switches and optos pass switch test.
Multiball drain stays in the outhole while more balls are served: stuck trough actuator
Cause: One of the trough switch actuators was caught on the mechanism that kicks balls from the trough into the shooter lane, so the game misread how many balls were in the trough.
Checks
- Check the right number of balls is installed.
- With the playfield up, work each trough switch actuator by hand and watch for one that catches on the ball-feed kicker.
- Run the ball-cycling (gumball) test for a while and watch the trough switch states.
Fix
- Free the stuck actuator and bend or adjust it so it moves without touching the feed kicker.
Systems
Games
Related tips
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Source: Pinball Repair help group!! (Facebook group)