What was found
CUSTOMER REPORTED VIBRATION, CLUTCH SLIPPING AND OIL IN TAIL PIPE. INCOMING DELTA P JUST BELOW LIMIT 21.7 PERCENT, 2.6 PSI. R & R, NO FAULT FOUND, PERFORMED ANOTHER DELTA P, FOUND ABNORMALLY LOW, 40 PERCENT NORMAL FOR DRY RBSH, WITH ANOTHER GAGE SET 3.7 PSI . DETERMINED TO TEAR DOWN ENGINE, FOUND RBSH TUBE CRACKED. OIL FEED TUBE CRACKED AND LEAKING OIL, RBSH 4-143-020-43, 190 HRS SINCE NEW. LOGBOOK REVIEW INDICATED THAT A PRIOR RBSH (R35 WITH 381.7 HRS TSN) WAS REMOVED IN 2009 FOR A BROKEN OIL FEED TUBE. ENGINE HAD SMOKE ON STARTING, OIL ON PT ROTOR AND IN TAILPIPE. THE ENGINE HAS BEEN OPERATED IN THE SAME AIRFRAME.