A CANADAIR CL65 IN CRUISE AT FL290 OPERATED THE R ENG AT IDLE DUE TO LOW OIL PRESSURE CAUSED BY 14TH STAGE COMPRESSOR BEARING SEAL FAILURE.

Narrative

OUR FLT WAS DELAYED FOR 1 HR DUE TO A MAINT PROB ON OUR INBOUND ACFT. THE INBOUND CREW HAD RECEIVED A 'R ENG LOW OIL PRESSURE' WARNING MESSAGE INBOUND. OUR MAINT CREW LOOKED AT THE ACFT AND HAD SIGNED THE ACFT AS GOOD TO GO. MAINT LISTED THE REPAIRS AS 'CHKED FOR OIL LEAKS; AND ADDED OIL TO THE ACFT.' ALL OF THE MAINT WORK WAS DONE BEFORE WE RECEIVED THE ACFT. UPON DOING MY PREFLT; I NOTICED NO DISCREPANCIES. THE TKOF; CLB; AND CRUISE WERE NORMAL. ABOUT 180 NM FROM BGR; WE RECEIVED A 'R ENG LOW OIL PRESSURE' WARNING MESSAGE. THIS OCCURRED AT FL290 AT .77 MACH. AFTER RECEIVING THE MESSAGE; WE COMPLETED THE 'ENG OIL LOW PRESSURE' EMER CHKLIST. UPON RETARDING THE THROTTLE; THE WARNING WENT AWAY AND THE PSI FLUCTUATED AROUND 25 PSI. EVEN THOUGH THE PSI WAS LOW; 25 PSI IS THE STEADY STATE IDLE LIMIT; SO WE DECIDED NOT TO SHUT THE ENG DOWN AFTER CONSULTING OUR DISPATCH AND MAINT CTL. WE DID NOT DECLARE AN EMER AND THE DSCNT AND LNDG WERE UNEVENTFUL AT BGR. MAINT MET THE ACFT AT BGR AND BEGAN PERFORMING MAINT CHKS. UPON COMPLETION OF MY WALKAROUND; THERE WERE NO OIL LEAKS. THE RETURN FLT WAS CANCELED AND THE CREW WAS SENT TO THE HOTEL. AS WE WERE LEAVING; THE MAINT GUY INFORMED US THAT HE ADDED 6 QUARTS OF OIL TO THE R ENG. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE WALKAROUND INSPECTION REVEALED NO OIL LEAKS FROM THE R ENG WHICH WAS WORKED ON PRIOR TO DEP FOR HIGH OIL CONSUMPTION. THE RPTR SAID THE AIRPLANE WAS IN BGR FOR 4 DAYS FOR THE ENG TO BE REPLACED. THE RPTR STATED MAINT FINDINGS WERE A FAILED 14TH STAGE COMPRESSOR BEARING SEAL ALLOWING THE OIL TO BE DUMPED INTO THE GAS PATH.