Do you have the schematic?

Also, instead of the replay button, have you tried the left or right coin chute switches? (They bypass some of the logic that the replay button path includes on the way to the Start relay.)

OK, so if the coin chute switches don't work, but tripping the Start relay does (and assuming the Start relay locks on), then that would narrow things down to either a normally closed switch at score motor position 1C or a normally closed switch on AX.

If the AX relay is in the backbox, then there's also a jones plug the signal has to go through. That could need cleaning, or have a loose wire. So that would be another place to check.

The lock-in path for the Start relay has to pass through everything else in the logic path 'behind' the motor 1C switch, so if the Start relay is working when manually activated, then that part of the path must be working.

There are two paths 'after' the AX switch; one goes through the Replay button, and the other goes through the coin chute switches. Since neither of those work, then that's why it has to be between the AX and motor 1C switches. Or the jones plug, if AX is in the backbox and not on the bottom cabinet board.

No, the AX relay shouldn't be energized or buzzing. It's an interlock style relay, so when activated, it latches closed and de-energizes. Then when the reset is complete, the AXR coil fires (AX Reset), which unlatches AX.

Which of the two coils is buzzing/active?

Score motor switch 1C is normally closed anyway (when the motor is at the home position, which is when position 1 is in the cam 'notch'.

So loud buzzing from AX (or AXR) is a problem, and that needs to be debugged. Need to know which of the two coils it is first though.

The problem is that motor switch 1C isn't in the path to AX or AXR (typically - at least not on similar era games for which I have schematics). And to activate AX, it requires a motor switch (like 2C), a switch on the Start relay (so S needs to be active), and possibly one more switch (depending on the game). So one score motor switch alone shouldn't trip AX.

And AXR requires two motor switches to be close (although both on at position 1).

Is the motor brake switch blade present? (single blade with a curve on the end, no wires attached, at position 3 1/2.)

By "lower latch coil" I'm interpreting that as being the AX Reset coil (the coil that would unlatch AX). A picture of which one you mean would be helpful though.

Sure, we like videos.

If both 1A and 1D switches are able to close, then yes, the AXR coil could be activating.

A drop of 3-1 oil in the oiling pad on the score motor (topside pad and underneath) may help. (Just ONE drop per pad.)

^^^

post it on youtube and give us the link...

The motor stops whenever all of the switches the feed it open (most or normally open, so usually only one or two are closed at a time to run the motor). Candidates typically include a switch on the Start relay, AX, and the home position switch at motor 1C. (If 1C isn't opening soon enough, it might be a cause.)

But the oil is for letting the motor clutch spin (not the motor itself), and if it's not able to well enough, the motor can also miss the stop at home. When the pads are dried out, this often doesn't work very well.

The clutch itself may have oil on it, but I'm only referring to the pads (to see the one on the bottom of the score motor, it needs to be flipped up and over a bit, and the one on top is covered by the cam, but there's an access hole when things line up).

Anyway, can you post a couple pictures of the 1D switch stack, both in the non-home and home positions, and also when it's in this 'overrun' position? That position is the level above the top cam, so will be activated by a post.

Switch 1D alone won't activate AXR; there's one other motor switch needed (could be 4A instead of 1A, as I'm not looking at a '300' schematic). But opening either one will deactivate AXR.

Great advice and patience Dirtflipper. You are to be commended. Looking forward to a YT video hopefully. I have a 300 and it's my wife's favorite pin. If I can chime in to help I will.

Is it stepping correctly through the player and ball counts? So if it starts on Player 1/Ball 1, after the ball drains, the Player Unit should step four times to reach Player 1/Ball 2 (on a one-player game). Then after the last ball drains, it should still step four times to reach Game Over.

On a four-player game, the Player Unit should step only once after each ball drains.

One thing to try is to just manually step the Player Unit to see if it can reach the Game Over state correctly. After starting a game, once the ball is at the plunger and the Player Unit is at Player 1/Ball 1, then manually step the plunger and watch it cycle through all player/ball counts, and then reach Game Over. If that works, then that indicates the Add Player Unit path is missing a step; if that doesn't work, then need to investigate a possible alignment issue on the Player Unit.

At that point, if you manually step the Player Unit, does the score motor then stop and the game reach Game Over?

Also, does the Last Ball relay activate, and does the Game Over relay activate?

Is the Ball Return relay ('O') staying active too?

Sounds like the game over state is being reached (since Last Ball and Game Over relays are cycling), but something is keeping the score motor running (obviously, and shouldn't).

So, need to work through the list of things that can run the score motor. On your schematic you'll find the score motor symbol ('M' inside a circle), and reading left to right you'll see all the switches (most in parallel) that when closed, cause the motor to run.

Outstanding! Congrats on hunting it down.

Way to go guys!! Dirt Flipper I have to say I'm extremely impressed!

Very cool another Gottlieb classic up and running!

There is some great info in this thread.
I just picked a cheap 300 that is having similar issues and following the same methodology I have the game playing and scoring but it doesn't seem to recognize when the ball hits the outhole. I can manually flip it into the shooting lane and it changes the ball in play but it will basically do that infinitely so obviously there is still an issue or two.
Also if I get the ball in the "mystery bonus" kick-out it will run the bonus balls forever and I noticed the "match numbers" are scrolling at the same time. This is my first Gottlieb and the schematics seem a bit harder to read but I have to dig into it a bit more, unfortunately it will have to wait until after the holidays. (unless somebody has a magic solution )

I have a Top Score (2 player version) and have been working off and on for a while now on the same or similar problems. First issue I had was the bonus balls were being kicked back and double counting bonuses or not counting them at all and being left for the next player/ball. I found that there is a wire catch that was stuck up and wasn't preventing balls from being kicked up the channel. The next problem was bonus balls were not being added (random bonus kick out) or subtracted (drain and add bonus kick out). I traced it back to the add bonus delay relay. A normally closed contact that isn't releasing. I replaced the capacitor in the add bonus delay circuit which didn't help. This is on a removable circuit board with a diode. If I remove it (circuit board) the machine will play fine except there's no delay which only comes into play every now and then. You may want to try that. Also clean the add bonus relay contact and the 500 point/add bonus relay contacts. I just purchased some jumper wires so I can hook my meter up to the add bonus delay relay and check solenoid voltage during play through the coin door.

Don't forget to check the switch in the trough that tells the machine it has bonus balls to count.

On a side note, here is a pic of the bonus ball assembly.176696.jpg

This is what was causing my bonus balls to miss-count. Look at the trough itself too. mine needed to be bent the TINIEST amount back away from the back glass so the balls could run down the trough like they should. Previously they had been leaning against the glass, and would NOT TOUCH the switch in the trough, until the next ball/player added another ball into the trough and it kicked everything loose.

Glad you figured it out!