As I own a 1972 Fireball, there are several things I can think of.

1. Wavy plastics. Mine still need to be flattened.
2. Zipper Flippers. Make sure all the "parts" are there.
3. Backglass. Plastic or glass? No flaking on the plastic, but check for scratches.

Good luck to you!

Is it supposed to be functional, or a project game?

In any case, congrats, this is a great game with some unusual cool features.

Hi Pinballocks
You think about buying a Fireball ?
Well, of course: Backglass Color ? , Playfield Color ?
And then the "Fireball specific features - do they work ?": Zipper-Mechanism*** of flippers ? , the "Turntable" works ?, the Mushroom-Bumpers work ?, the left-bottom Kickout-Kicker works ?, the two Eject-Holes work ?

Zipper-Mechanism***: ipdb -> http://www.ipdb.org/machine.cgi?id=852 -> schema -> at E-34 is the "closing coil" and the 1.25 Amp Fuse (for this coil). IF (if) a preowner was tired of replacing blown 1.25 Amp Fuses and has put-in there a 10 to 15 Amp Fuse -> the windings in the coil may be shut (insulation overheated, melted) and the coil has to be replaced - very hard to get such a Coil ...

Hihi, we german speaking pinball-addicts sometimes try to get help from pinsiders - here: http://www.flippermarkt.de/community/howto/cms/pages/reparaturanleitungen/spulen-wickeln.php -> the fixing of such a Zipper-Flipper-Mechanism-Coil.
Greetings Rolf

Fun game! Not sure if it's like 4 Million BC, but 4 Million has a ax/bx relay that would keep track of the multiball. If it was in the wrong possition (after a cleaning or removing a ball in the tar pit), it would think there should be two balls on the playing field and want to knock two balls into the shooter lane.

Looking forward to picks! Here's a nice video of a guy showing some the layout of a Fireball.

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