As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI OUT, LT HYDRAULIC SYSTEM LOW QTY EICAS MESSAGE IN VIEW STATUS PAGE SHOWS ZERO QTY. AICRAFT BACK TO BLOCK AND GROUNDED. UPON INSPECTION FOUND LEAKING RETURN LINE FROM EDP IN THE LT PYLON. REMOVED LINE, REPAIRED HYD LINE WITH RYNGLOK, REF B767 MM 20-10-09, LINE LEAK CHECKS GOOD. REINSTALLED LINE, REF AMM 20-10-09. SYSTEM LEAK CHECKS GOOD. AIRCRAFT RELEASED.