I'm mostly replying to this because I got a kick out of your terminology of "booting up" your EM. Along those same lines, I woke up this morning, and the first thing I did was "boot up" my bathroom light

Anyway, the "boot up" sequence when you turn power on your machine should not include energizing the Tilt Hold (H) relay. This machine should start "Tilted" (unless you modify it). All that should happen when you turn power on is the Gameover and First Ball relays should energize. There are several relay switches that can start the score motor, but I would put my money on the old AX relay. Why don't you lift up the playfield so you have full view to the relays, put a piece of paper across the AX relay motor control switch contacts to temporarily block that circuit, then flip the power switch on and see what happens. Again, the only thing that should happen is Gameover and First Ball relays energize. If the score motor doesn't run, then you know it's the AX relay switch causing that. If the Tilt Hold relay energizes, then that could be another switch on the AX relay - a make-break that might be a marginal make-make now because it's not adjusted correctly - it would provide a path for the "H" relay to energize (and once it does it locks in).

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Oops, one clarification to what I said in the last post - on this machine the Tilt Hold Re. may indeed lockin when you turn on the power (most Gottliebs will turn on in Tilt Mode, but not necessarily this one). The reason is because when you turn on power, the Outhole relay will pulse for a fraction of a second before the Gameover Re. energizes and that's long enough for the Tilt Hold Re. to lockin via the "O" switch. It happens so fast that the Outhole relay doesn't even deflect enough to close it's own lockin switch or initiate score motor movement because the circuit is opened by the "Q" switch so quickly - at least that's how it works on my machine. Now, of course, it won't happen when you have the playfield up because the Ball Return Switch won't be closed. Anyway, it may depend on how you have all these switches gapped on whether the Tilt Hold Re. energizes or not, but in the end it really does not matter because it will energize via the AX relay switch when you start a new game. Your problem is really the runaway score motor. I just wanted you to be armed with all this data before you started troubleshooting. Good Luck!
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