As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
REMOVED AND REPLACED SERVO WITH AN OVERHAULED SERVO. UPON GROUND RUN AND LEAK CHECK, PILOT STATED: ON START, AIRCRAFT CYCLIC WENT FULL LEFT. COULD NOT GET CENTERED. PILOT SHUT DOWN AIRCRAFT BEFORE POSSIBLE ROLL-OVER. REMOVED AND INSPECTED SERVO. FOUND PILOT VALVE ON SERVO HITTING COVER PLATE OF SERVO. SENT BACK TO REPAIR OPERATOR FOR EVALUATION.