What was found
(CAN) ON TAKE OFF, BOTH ENGS PRODUCED NORM TAKE OFF PWR AT 400 FT AGL, CAPT CALLED FOR CLIMB PWR, RT ENG POWER REDUCED TO 30 PERCENT TORQUE. A/C RETURNED TO LAND WITH RT ENG SHUTDOWN & RT PROP FEATHERED. MAINT RECEIVED A/C WITH RT PROP FEATHERED. PROP WAS UNFEATHERED & VARIOUS FUEL CONTROL & SHUT OFF COMPONENTS CHECKED FOR PROPER OP. NO FAULTS FOUND. GRD RUNS CARRIED OUT. NO FAULTS FOUND. A FLT TEST REQUESTED & CARRIED OUT, NO FAULTS FOUND. A/C RELEASED FOR SERVICE. 4 FLTS LATER, PILOT REPORTED TORQUE TEMP LIMITING SYS TEST PRODUCING ABNORMAL LARGE DROPS IN TORQUE, TEMPS & FUEL FLOW. SYS IS ACTIVE DURING TAKE OFF & ITS PURPOSE IS TO PREVENT DAMAGING ENG WITH EXCESSIVE TORQUES OR TEMPS.