As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - ON FLIGHT 2451, 100 MILES OUT OF PDX NR 2 HYDRAULIC SYSTEM FAILED. FLIGHT RETURNED TO PDX AND ACCOMPLISHED A UNEVENTFUL LANDING. SHUTOFF VALVE TO NR 2 SYSTEM WAS CLOSED FOR 25-30 MINUTES. MAINTENANCE FOUND SKYDROL LEAKING AT THE EXIT FOR THE HEAT EXCHANGER. REPLACED THE HEAT EXCHANGER. OPERATIONAL CHECKS GOOD. PERFORMED REQUIRED INSPECTIONS FOR ENGINE DRIVEN PUMPS OPERATING WITHOUT FLUID. CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.