AT APPROX 12:30 AM THE PRODUCTION HOIST KICKED OUT. INVESTIGATION FOUND THAT THE NORTH BRAKE AIR VALVE WAS STICKING. IN ORDER TO CHANGE VALVE, HOIST HAD TO BE TAKEN OUT OF SERVICE. (EVACUATIO N INSTALLED NEW VALVE, COMPLETED AT 2:05 AM, READJUSTED AIR REGULATORS. MSHA NOTIFIED, NEWARK AT 2:25 AM (MESSAGE).