What was found
FOLLOW-UP TO #1 ENGINE IDG FREQUENT SERVICING, ACCOMPLISH IDG STATIC LEAK CHECK REF B737-9 AMM 24-11-00-700-801. GROUNDED - YES. ACCOMPLISHED STATIC LK CK REF B737-9 AMM 24-11-00. MONITORED PRESSURE FOR 45 MINUTES WITH NO DROP. WITH STATIC CHECK PASS, PERFORMED ENGINE RUN. AT 8 MINUTES, IDG BEGAN LEAKING FROM DRAIN LINE. REMOVED IDG AND CONFIRMED OIL LEAKING FROM IDG SIDE SHAFT SEAL (BAD IDG). REPLACED IDG REF AMM 24-11-11. LK AND OPS CKS GOOD. ETOPS GROUND VERIFICATION SUCCESSFUL.