What was found
LANDING GEAR DID NOT RETRACT WHEN GEAR HANDLE WAS SELECTED UP. INDICATION WAS 3 GREEN WITH A RED LIGHT. WHEN THE GEAR HANDLE WAS REPLACED IN THE DOWN POSITION, INDICATION WAS 3 GREEN. AFTER LANDING, A SMALL BOLT WAS OBSERVED AS MISSING FROM THE SQUAT SWITCH ON THE LT MAIN GEAR. PERFORMED A VISUAL INSPECTION OF THE LT MAIN LANDING GEAR SQUAT SWITCH. FOUND THE SWITCH ROLLER, AND THE ATTACHING HARDWARE OF THE ROLLER MISSING. R & R THE LT MLG SQUAT SWITCH WITH A NEW SWITCH IAW THE MM 32-61-00. OPS CHECKED NORMAL.