As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OIL FILTER ADAPTER LONGITUDINAL HOLE IN PISTON DOES NOT INTERSECT HOLES DRILLED THROUGH THE CIRCUMFERENCE. NO OIL IS ALLOWED TO THE FILTER ELEMENT. REPLACED PISTON, OPERATION RETURNED TO NORMAL. SUBMITTER STATED PART WAS NOT MADE ACCORDING TO PRINT.