As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING AN ENGINE GROUND OPERATION THE HYDRAULIC PUMP OUTPUT CEASED. A SHEARED PUMP EXTERNAL DRIVE SHAFT WAS DISCOVERED. SYSTEM REGULATION AND RETURN FILTERS AND PUMP HOSES SHOW NO INDICATIONS OF METAL CONTAMINATES. THE PUP STUB SHAFT STILL TURNS BY HAND. REMOVED PUMP ASSEMBLY FROM SERVICE AND INSTALLED AN OVERHAULED PUMP. (K)