As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER DEPARTURE, THE ACFT ENCOUNTERED A YELLOW HYD SYS OVERHEAT. IN CONSULTATION WITH MX AND FLIGHT DISPATCH, THE ACFT WAS DIVERTED BACK TO POINT OF DEPARTURE. THE ACFT LANDED APPROX 7000 KGS OVER THE MAXIMUM LANDING WEIGHT. THE LANDING WAS OTHERWISE UNEVENTFUL. CHECK VALVE REPLACED YELLOW 23083GMAS IAW AMM 29-24-21-000-001.