A 630 SCOOP WINCH WAS BEING USED TO PULLED BROKEN BELT TOGETHER. INJURED WAS GIVING DIRECTIONS TO THE SCOOP OPERATOR, THE WINCH ROPE WAS THRU A BLOCK BRATTICE. WHEN THE WINCH ROPE BECAME TIGHT IT CAUSED A LOOSE BLOCK TO THE THROWN. THIS BLOCK STRUCK INJURED ON HIS LEFT SHOULDER AND NECK.