What was found
PILOT REPORTED, ON CLIMB OUT, THE RT ENGINE LOST ALL POWER AND THE ACFT YAWED RT. HE FEATHERED AND SHUTDOWN THE RT ENGINE AND RETURNED TO BASE. MX DETERMINED THE FUEL SERVO TO BE THE CAUSE, A REPLACEMENT SERVO WAS INSTALLED AND ENGINE OPERATION RETURNED TO NORMAL. THE AFFECTED SERVO WAS RETURNED TO THE OVERHAULER WITH AN EVALUATION REQUESTED. THE OVERHAUL SHOP FOUND THE REGULATOR RETAINER NUT HAD BACKED OFF COMPLETELY; THE REGULATOR ASSY WAS CLEANED AND REASSEMBLED WITH A NEW LOCKNUT. ON BENCH TEST, SERVO OPERATION RETURNED TO NORMAL. SB 77-1 CALLS FOR LOCKTITE ON THE REGULATOR STEM, LOCKTITE WAS FOUND APPLIED TO THE STEM AS REQUIRED.