As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GENERAL HYDRAULIC SYSTEM QUANTITY DECREASED FROM FULL TO JUST ABOVE STAND PIPE DURING INITIAL CLIMB. REPACKED O-RING AT RESTRICTOR VALVE GOING TO THE ASPIRATOR ON THE MAIN HYDRAULIC RESERVOIR. LEAK CHECKED GOOD. SERVICED HYDRAULIC SYSTEM.