What was found
CREW EXECUTED AN AIR RETURN AFTER DISCOVERING OIL QTY ON NR 1 ENGINE DROPPED TO 5.5 FROM 18.0 ON CLIMBOUT THROUGH 2,000 FT. LANDED WITHOUT INCIDENT. FOUND EVIDENCE OF OIL LEAK IN DEOILER BREATHER TUBE. FOUND DEOILER SEAL ASSY DAMAGED. R & R DEOILER SEAL ASSY IAW AMM 72-60-31. PERFORMED ENG 1 IDLE RUN. NO LEAKS FOUND.