What was found
NR 1 ENGINE SLOW TO COME OUT OF FEATHER. NR 1 PROPELLER GREASE LEVEL IS NORMAL, NO SIGNS OF LEAKAGE AT THE NR 1 PCU AND OSG. PROPELLER WILL NOT UNFEATHER ALL THE WAY IN MANUAL MODE, ONLY MOVES A FEW DEGREES. PROP TIME TO UNFEATHER TEST WITH ENGINES RUNNING TAKES APPROX 30-40 SECONDS AND IS ALSO SLOW TO FEATHER. REPLACED THE PROPELLER PISTON SEAL IAW 61-10-00-960-801. SERVICED THE PROPELLER GREASE LEVEL IAW 61-10-00-640-801. FUNCTIONAL TEST OF PROPELLER TIME TO UNFEATHER FAILED. PROPELLER WILL NOT UNFEATHER MANUALLY. ON NR 1 ENGINE START WITH CONDITION LEVER IN START - FEATHER & POWER LEVER AT DISC, THE NR 1 PROPELLER RPM COMES OUT OF FEATHER AND PROPELLER RPM STABILIZES AT 420 RPM. REMOVED THE THR NR 1 BETA TUBE IAW MTC 6610001. REMOVED AND REPLACED THE NR 1 PITCH CONTROL UNIT IAW AMM 61-20-11-000-400-801. REINSTALLED THE NR 1 BETA TUBE IAW MTC 6610002 AND MTC 6710006. NO LEAKS NOTED. NR 1 FEATHER WITHIN TIME FRAME AND UNFEATHERS PROPERLY.