As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
O-RING IN THE LT MLG RETRACT CYLINDER FAILED WHICH ALLOWED THE HYD SYS OIL TO DRAIN. O-RING WAS MOST LIKELY DAMAGED DURING INSTALLATION. DURING INSTALLATION OF THIS PART O-RING LUBE OR HYDRAULIC OIL MUST BE USED TO KEEP UNIT FROM BEING DAMAGED.