1972 Gottlieb King Kool stopped kicking ball out

Maybe this could help?

http://user.xmission.com/~daina/tips/pub/tip0450.html

"7. When 'DB' relay is in a setup position, the motor continues to run and all score units reset to zero through motor 1A, motor 4A, and the reset control switches on 'DB' When all score units are reset to zero and motor 2B switch makes, 'DB' relay is tripped completing the reset cycle.
8. Place the ball in the out hole. When the ball makes the outhole switch, 'O' relay is actuated through a normally closed switch on 'DB'.
9. 'O' relay locks in through its own switch and a switch on motor 2B.
10. When 'O' relay is energized the motor starts running.
11. Motor 4C actuates the ball return coil through a switch on 'O' relay.
12. The ball return kicks the ball across the trough switch which steps the ball count unit once, indicating first ball in play.
13. The ball is now in the runway and ready to be shot onto the playfield."

It's for Flying Carpet, also a 1972 Gottlieb, so hopefully close enough to apply. If there is a DB relay on the reset bank of King Kool, then I'd check it for a dirty/misadjusted switch.

https://groups.google.com/forum/#!topic/rec.games.pinball/Gt9DHhwb8Es

This thread suggest that XB may the equivalent on multiplayer games to the DB on single player games like Flying Carpet. So I guess check XB for a misadjusted switch. Probably something that looks like it's closed, but if you check for continuity between the switch lugs it will be open instead.

"If the ball is in the outhole, the "O" relay activates. The "O" relay,
through the score motor and a switch on relay "XB", will kick the ball
to the shooter lane. Note: the "O" relay will not activate unless the
bonus unit (if the game has one) is reset to zero (there is a bonus
unit zero position switch).
When the ball re-enters the outhole after game play, the "P" relay
kicks the ball back to the shooter lane. Switches on the "XB", "ZB",
"P" relays and some score motor switches advances the player unit (if
present) and player relays ("PBx")."

Woo! Glad the copy and paste helped.