What was found
RETURNING TO BLOCK AFTER TAXI FOR ENGINE MAINTENANCE GROUND RUNS, LT FWD AND AFT BRAKES NOTED AS VERY HOT, SUBSEQUENTLY LT FWD BRAKE CAUGHT FIRE AND WAS QUICKLY EXTINGUISHED BY GROUND CREW. C/W LAC JOB CARD HN32144, REPLACED LT BRAKE CONTROL VALVE (SUSPECTED DISCREPANT PART), LT FWD AND AFT BRAKES, WHEELS AND TIRES. ALSO REPLACED LT NORMAL AND EMERGENCY BRAKE HOSES, SHUTTLE VALVES, BRAKE FUSES AND SWIVELS PRECAUTIONARY. BRAKE BLEED AND LEAK CHECK IAW SMP581 29-00 LOG PAGE 27338 ITEM M3 THR M19 BRAKE CONTROL VALVE SENT TO VENDOR FOR TEAR-DOWN AND INSPECTION.