What was found
DURING CRUISING, APPROX 1 HR AFTER TAKING OFF WITH FULL FUEL, RT FUEL FILTER BY-PASS & MASTER CAUTIONS ILLUMINATED. RT BOOST PUMP TURNED ON. 10 MINS LATER, LT FUEL FILTER BY-PASS ILLUMINATED. LT BOOST PUMP TURNED ON & AN EMERGENCY DECLARED. DURING DESCENT, HEARD WHAT SOUNDED LIKE A MILD COMPRESSOR STALL FROM 1 OF ENGS. ENG INSTRUMENTS INDICATED NORMAL. A/C MADE AN UNEVENTFUL LANDING. MX REPLACED FUEL FILTERS. FUEL FILTERS & SAMPLES SENT FOR ANALYSIS. FILTERS & FUEL FROM BOWL SENT TO BE TESTED. DRAINS SUMPED, & ENGS RAN. FUEL FILTERS REPLACED & DRAINS SUMPED FOLLOWING ENG RUN. FILTERS REMOVED ALONG WITH FUEL FROM BOWL SENT FOR TESTING OF WATER & CONTAMINANTS. TESTS NEGATIVE. A/C RETURNED TO SERVICE.