As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SLOW LOSS OF HYDRAULICS OBSERVED ON HYDRAULIC QUANTITY GAUGE. NEEDLE WENT FROM FULL TO HALFWAY BETWEEN N AND STANDPIPE. EMERGENCY PROCEDURES ACCOMPLISHED. REPLACED NR 3 ENGINE HYDRAULIC PUMP PRESSURE LINE AND RESEALED PUMP FITTING AT PUMP. SERVICED HYDRAULIC RESERVOIR. PERFORMED GROUND RUN AND LEAK CHECKED. NO LEAKS NOTED IAW DC8 MM.