What was found
ON TAKEOFF ROLL, PWR APPROX 80-90 PERCENT, LT THRUST REVERSER ARM AND UNLOCK LIGHT CAME ON. AS WE TAXIED IN, FULL T/R DEPLOYMENT ON LT SIDE; EMER SWITCH STOWED T/R. REENABLED T/R SYS. CYCLED T/R'S AND DUPLICATED MALFUNCTION. GAINED ACCESS TO THROTTLE GUARD. TR SWITCHES AND FOUND SWITCH CAM LOOSE AND NOT ADVANCING WHEN THROTTLES WERE ADVANCED. TIGHTENED CAM HARDWARE AND CK'D SWITCH RIGGING TR SYS OPS CK'D GOOD IAW MM CHP 78-31-00.