First off, welcome to PinSide and congrats in acquiring your first machine.

I'm not familiar with the lock mech in Gilligan's Island, so please bare with me.

Are the balls getting caught, because of that plastic in your photo?

If yes, then the nuts are too tight on the screws. Loosen up the nuts a little, so the plastic can flex and shift a bit. Having the nuts too tight will also eventually crack the plastic.

I'm not sure which type of switch that Left Lock has. If it's an opto, then it's possible that you polished the plastics a little too good and it's throwing off the optical beam.

Are you talking about the Lagoon shot?

The Turtle Eggs shot goes under the island and feeds the saucer and pops, there's no lock there. The Lagoon shot goes under Kona and to a coil under the plastic you've circled. There's a switch there so the game knows when to kick the ball back out into play. If the switch doesn't work the ball will just sit there. You say the coil does work in test mode?

Everything is below the playfield except the coil which sits on top. It's a bear to get at because of all the layers of plastics and the island in that area. On my old GI that coil had failed so rather than fix it the previous owner screwed a post into the playfield blocking the Lagoon shot completely.

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