As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SIGHT GLASS O-RING IN HYD RESERVOIR APPEARS TO BE OF A NON COMPATIBLE MATERIAL WITH SKYDROL. CAUSING O-RING TO DISINTEGRATE LEAVING PIECES OF O-RING MATERIAL IN RESERVOIR AND CAUSING SIGHT GLASS TO LEAK. THIS COULD CAUSE HYD SYS CONTAMINATION OR LOSS OF HYD POWER. (K)