I have a 1973 Williams Gulfstream. It was playing perfectly until recently. During normal play, game will go "dead" (lights on but flippers don't work and nothing will score).

Where it is at now...When ball drains, score motor runs continuously but ball does not kick out. If I kick out ball manually, the score motor will stop but the flippers are still dead and no switches will score. Sometimes if I slap the flippers while the score motor is running, the ball will kick out and game will play normally for a while.

Kick out relay seems to be OK since it works sometimes. Anyone have any ideas? I'd love to get this running for a New Year's Eve party.

I have a schematic and the manual is here http://mirror2.ipdb.org/files/1094/Williams_1973_Gulfstream_Instruction_Manual.pdf

Fixed it. Traced it back to a dirty switch on the Game Over relay.