That's pretty much where I'd start.

On top of that, check the playfield fuses and the main solenoid fuse near the transformer.

After that, check kickout coil's resistance, possibly replace the diode, check for continuity back to the driver board, and check the driver board transistor for the coil.

Pretty much everything you would normally check on other games.

Also visit some of the IPDB pages for system 3 games if you want to familiarize yourself with what the innards look like as well as the pinwiki page.

Gottlieb doesn't have a kickout mechnism like Williams had. It has a mechanism that allows 1 ball to roll to the shooter lane, like a gate. Most coil controlled mechanisms in Gottlieb do have their own fuse. Beside the "common" solenoid fuse at the transformer assy, it is worth to check the fuse involved. Also....the rails inside the trough can develop "dents" over the years preventing the balls to roll to the shooter lane. This is very common.

Marco

Fuses are on the underside of the playfield and at the bottom of the cabinet near the transformer.

Yes, plan on taking off the apron.

If I had to guess, your problem is most likely due to pitting in the ball guide where the balls rest in the trough, this seems to be a VERY common issue on System 3s.

To check, with the glass off, and looking in the shooter lane where the ball comes out of, start a game. If you hear or see the solenoid activating, but no ball pops out, you can be pretty well sure the trough has pitting.

To fix, pop off the ball apron, remove the balls from the trough, and file down the metal trough guides with a metal file.

The owner that purchased my gladiators is having an odd issue with the trough.

I had him take the apron off and get some video and pics.

I don’t have a sys3 at home anymore so I don’t remember how the trough works fully and there isn’t much on YouTube or pics.

Do all balls sit in the trough while leaving the drain empty? It looks like the ball releases to the shooter lane fine, then the ball in the drain tries to fire to the trough and bounces back.

Here is the ball bouncing back

Just found the drain switch was catching on the trough metal, is that switch to make sure two balls aren’t in the drain?

Here is the switch that is catching

Thanks for any help!
6FEE7FF2-28B4-4C34-BC7C-6D74D6DDDC7F (resized).jpeg

EDIT: they found 5 balls in the game and a 4 ball sticker.... so looks like potentially a new drain switch and taking a ball out.