What was found
(CAN) WHILE DOING SPECIAL INSPECTION, IT WAS NOTED DURING O RING REPLACEMENT THAT SOME MATERIAL WAS MISSING ON TRANSFER TUBE WHERE THE O RING SITS. ON A PREVIOUS INSPECTION FEW DAYS EARLIER, THE SAME SITUATION WAS OBSERVED ON ANOTHER ENG PW150. IN BOTH CASES THE TRANSFER TUBES WERE REPLACED & MFG WERE CONTACTED TO DECLARE THE SITUATION. NOBODY WAS AWARE OF THIS PROBLEM IAW AMM 73-11-01-00-801 400-801 ET EIPC 73-11-00 FIG 7 ITEM 135.