As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AIRCRAFT TURN BACK DUE TO LOSS OF HYDRAULIC FLUID SYSTEN B IN FLIGHT. ON INSPECTION FOUND PLUG ON NR2 SPOILER ACTUATOR LEAKING. REPLACED PLUG P/N 66-22774-1 IAW CMM OVH 27-60-41. B SYSTEM CASE DRAIN FILTER TO B SYSTEM PRESS FILTERS CHECKED FOR CONTAMINATION. NO CONTAMINATION FOUND. FUNCTION CHECKED SPOILERS AND LEAKED CHECKED. OK FOR SERVICE. CARRIED OUT RII INSPECTION. OK.