EE WAS CHECKING #1 CLINKER COOLER DRIVE MOTOR. IT HAD STALLED BUT WAS SHOWING A RUN FROM THE OPERATOR'S PANEL. HE REMOVED THE GUARD FROM THE MOTTOR-GEAR REDUCTION COUPLING TO SEE IF HE COULD S PIN IT BY HAND. FAILING THIS, HE TOLD THE OPERATOR TO SHUT THE DRIVE OFF. THE BACKLASH CAUSED THE COUPLING TO SPIN IN REVERSE, SNAGGING HIS GLOVE, PULLING HIS ARM AROUND THE SHAFT OF THE MOTO