A B737-300 HAD THE R ENG IGNITION EXCITER REPLACED FOR A NO START PROB. THE NEXT START ATTEMPT; THE STARTER FAILED.

Narrative

THIS RPT IS ABOUT AN ENG STARTING INCIDENT AFTER #2 ENG MAINT ON THE R IGNITOR SYS. AFTER PUSHBACK FOR FLT XXXX WE HAD 2 UNSUCCESSFUL STARTS OF THE #2 ENG FOR NO IGNITION WITHIN 10 SECONDS OF MOVING THE START LEVER TO IDLE. EACH TIME WE ACCOMPLISHED THE ABNORMAL ENG START/TAILPIPE FIRE CHKLIST AND COORDINATED WITH MAINT. WE RETURNED TO THE GATE AND OFF LOADED THE PAXS. A CONTRACT MECH COMPLETED MAINT ON THE IGNITOR SYS AND WE WERE ASKED TO DO AN ENG RUN TO TEST THE IGNITOR REPAIRS. ON THIS START THERE WAS NORMAL IGNITION AFTER MOVING THE START LEVER TO IDLE. THE START SEQUENCE WAS NORMAL UNTIL APPROX 40% N2; EGT APPROX 450. AT THIS POINT WE HEARD AN ABNORMAL NOISE AND THE CONTRACT MECH DIRECTED THE ENG BE SHUT DOWN. THE START LEVER WAS MOVED TO CUTOFF AND ALL ENG INSTS INDICATED THE ENG WAS SHUTTING DOWN PROPERLY. THE CAPT VERIFIED WITH THE MECH THAT THERE WAS NO FIRE; AND THAT NO PERSONNEL WERE INJURED. AFTER VERIFYING ENG PARAMETERS; THE CAPT ELECTED TO LEAVE THE COCKPIT TO DETERMINE THE NATURE OF THE PROB. PRIOR TO LEAVING; THE CAPT DIRECTED THAT I ACCOMPLISH THE PARKING CHKLIST. I DID THIS IMMEDIATELY. THE CAPT RETURNED WITHIN 30 SECONDS STATING THAT IT SOUNDED LIKE AN ENG WAS STILL RUNNING. WE REVERIFIED ALL ENG PARAMETERS; BOTH N1 AND N2 WERE 0; AND EGT NORMAL FOR ENG SHUTDOWN. THE CAPT ONCE AGAIN LEFT THE COCKPIT TO DETERMINE THE SOURCE OF THE ABNORMAL NOISE. THE CAPT RETURNED SHORTLY; RE-VERIFYING ENG PARAMETERS AND COCKPIT SWITCHES; DISCOVERING THE R START SWITCH WAS STILL IN THE GND POS. CAPT SELECTED THE START SWITCH TO OFF AND THE APU SWITCH TO OFF AS WELL. THE ABNORMAL NOISE TERMINATED. WHILE I CANNOT PUT AN EXACT TIME TO THE SEQUENCE; I DO BELIEVE THE TOTAL ELAPSED TIME FROM THE TIME THE CAPT LEFT THE COCKPIT THE FIRST TIME UNTIL THE START SWITCH WAS SELECTED TO OFF POS WAS LESS THAN 2 MINS. IN RETROSPECT; IT IS APPARENT THAT WE SHOULD HAVE COMPLETED THE ABNORMAL ENG START/TAILPIPE FIRE CHKLIST PRIOR TO LEAVING THE COCKPIT THE FIRST TIME TO DETERMINE THE CAUSE OF THE ABNORMAL NOISE. ADDITIONALLY; SINCE BOTH THE N1 AND N2 WERE 0; WE DID NOT IMMEDIATELY ASSOCIATE THE NOISE WITH ENG STARTER FAILURE.