the usual cause is multiple search wipers spinning at the same time and/or the wipers not being locked in the correct position.
the wipers should be locked at position 50 as shown in the manual diagrams on pages 7,9 and 11.
for multiple search wipers spinning at the same time, there's a "search ratchet pin switch" which the manual decided not to show...assuming it's like the other 6 card games and is activated by a peg sticking out of the metal search index ratchets/gears. There's a pin switch/peg on the 1-2 and 3-4 search ratchets which pulses a switch closed when each of those search wipers is rotated almost all the way home. The switches are responsible for releasing the next wipers.
e.g. when the 1-2 search wipers are spun almost all the way around, the 1-2 pin switch pulses closed and releases the 3-4 wipers. The 1-2 wipers lock back home almost immediately.
possible problems are:
- the pin switches are stuck closed
- the ratchets are installed 180 degrees wrong on the wiper shaft and the wipers for the next two cards are releasing too early.