What was found
EN ROUTE, SHORTLY AFTER POWER WAS REDUCED TO BEGIN DESCENT FROM CRUISE ALTITUDE, BOTH ENGINES EXPERIENCED A SUSTAINED POWER LOSS. UNABLE TO RESTART EITHER ENGINE IN FLT. EMERGENCY DECLARED & ACFT DIVERTED. UNDER NTSB INVESTIGATION. MX REPLACED AIRFRAME & ENGINE FUEL FILTERS. CHECKS PERFORMED ON IGNITION ANTI-ICE, FUEL TEMP, AIRFRAME FUEL FILTER BY-PASS INDICATION SYS, NO DISCREPANCIES. LT & RT ENG P-3 BOSSES INSP FOR WORN GASKETS. NO LEAK OR DAMAGE. ENG OIL SOAP SAMPLES & FUEL SAMPLES TAKEN. RT ENG REPLACED, 5 PT ENG RUNS PERFORMED ON LT & RT POWERPLANTS. REMOVED ENG WILL BE TORN DOWN BY MANUF AS PART OF NTSB INVESTIGATION. THREE GROUND POWER RUNS WERE COMPLETED, NO NOTED PROBLEMS.