What was found
AFTER TAKEOFF, LEFT MAIN GEAR FAILED TO FULLY RETRACT. BOTH A AND B RED LIGHTS REMAINED ILLUMINATED. RETURNED TO FIELD. TOOK AIRCRAFT TO GARRETT, SWUNG LANDING GEAR. ALL DOORS WOULD NOT CLOSE. CHANGED GEAR DOOR SEQUENCE VALVE, ADJUSTED LEFT STRUT GEAR ACTUATOR, AND SWUNG GEAR NUMEROUS TIMES. OPS CHECKS GOOD.