What was found
CLIMBING THROUGH 11,000', THE MASTER WARNING LIGHT FLASHED & THE RT LOW OIL PRESS ANNUNCIATOR ILLUMINATED. THE RT OIL PRESS TAPE WAS AT ZERO, LESS THAN 5 SECONDS. CREW GOT OUT CHECKLIST, BUT RT OIL PRESS RETURNED TO NORMAL AFTER POWER WAS REDUCED. NO VISIBLE OIL LEAKS ON POST FLIGHT. REMOVED RT ENG PN 31J1900-01, SN PCE-DB0623, IN AN UNSERVICEABLE CONDITION & INSTALLED A REPAIRED SERVICEABLE RT ENG PN 31J1900-01, SN PCE-DB0356. PERFORMED LEAK & OPERATIONAL CHECK OUTS WITH NO DEFECTS NOTED. ALL WORK PERFORMED IAW AMM 71-00-00 & PWC 545A EMM 72-00-00.