As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI OUT FA REPORTS HEARING LOUD METALLIC BANGING NOISE FROM RIGHT AFT LOWER AIRCRAFT. GROUNDED - YES. REMOVED AND REPLACED SURGE CONTROL VALVE REF AMM 49-52-41. IN ADDITION REMOVED AND REPLACED THE STARTER-GENERATOR AND LUBE FILTERS. REF AMM 49-91-12. TWO CB'S RESET. OPS/LEAK CHECK GOOD FOR BOTH FILTERS AND SURGE CONTROL VALVE.