What was found
NR 2 ENGINE OIL FILTER BYPASS LIGHT ILLUMINATED DURING CRUISE AT FL 350 AND DID NOT EXTINGUISH WITH THE THRUST LEVER AT IDLE. ACFT GROUNDED. INSPECTED THE NR 2 ENGINE AND FOUND NOISY WHEN PULLING BLADE THROUGH ROTATION. INSPECTED THE MCD AND SCAVENGE FILTER IAW AMM 79-00-00-200-804-F00. FOUND SUBSTANTIAL METAL DEBRIS ON AGB/TGB, MCD, AND N2 SPEED SENSOR. NO METAL DEBRIS NOTED ON STARTER MCD AND SCAVENGE FILTER. REINSTALLED N2 SPEED SENSOR IAW AMM 77-11-02, AND AGB/TGB MCD IAW AMM 79-21-05. REMOVED AND REPLACED THE NR 2 ENGINE IAW T/C 78471000, AND 78471001, NO OIL BYPASS NOTED DURING ENGINE RUN. VERIFICATION FLIGHT SATISFACTORY.