The trough serves a ball late, then not at all. Balls can be heard rolling in the trough but are not reaching the eject position.
Balls hang in the trough and none is served: divots in the trough floor
Cause: Wear divots in the bottom of the gravity trough where the balls rest, which hold them back. Magnetized or very shiny balls can add to it.
Checks
- Pull the balls and look and feel along the trough floor for dents or worn pockets.
- Try a fresh set of plain steel balls to rule out magnetized ones.
Fix
- Slide a clear plastic trough liner into the trough so the balls roll over a smooth surface, or sand the divots smooth.
Systems
Games
Related tips
- Balls hang in the trough: divots in the trough metal
- Old and new WPC ball trough designs
- Opto ball troughs from Indiana Jones on
- Two balls served at start and the lock spits its ball out: count the balls
- Full ball trough opto test in switch edge test
Source: Pinball Repair help group!! (Facebook group)