A B757-200 FLC RPTS BEING UNCERTAIN OF THE R ENG START VALVE CLOSED INDICATIONS AFTER ENG START.

Narrative

AFTER ENG START AT SAT; FO ADVISED ME THAT HE WAS NOT SURE HE SAW THE R ENG START VALVE IN-TRANSIT DISAGREEMENT LIGHT BLINK ON AND OFF AT STARTER CUTOUT. HE DID OBSERVE THE START SWITCH RETURN TO AUTO; THE PNEUMATIC DUCT PRESSURE RISE; AND NO EICAS MESSAGE TO INDICATE ANYTHING OTHER THAN A NORMAL START. INDICATOR LIGHTS TESTED NORMAL AND CIRCUIT BREAKERS WERE NORMAL. ALL ENG PARAMETERS WERE NORMAL. IN VIEW OF THIS INFO; I DECIDED SYS WERE NORMAL AND THE ACFT SAFE TO CONTINUE. ENRTE; THE FO AND I DISCUSSED THIS SIT FURTHER AND DECIDED TO CONSULT MAINT. WE WERE NOT SURE A PROB EXISTED; BUT WANTED TO INSURE MAINT X WAS IN THE LOOP. WE WERE INBOUND TO A NON-MAINT STATION. CONTACT WAS MADE. WE ADVISED WHAT WE THINK WE SAW. THE ITEM WAS DEFERRED AND LOGBOOK ENTRIES WERE MADE. THE MAINT CTLR WAS CONCERNED WHY WE WERE AIRBORNE WITH THIS PROB. WE AGAIN STATED IT WAS AN UNCONFIRMED PROB. WE LANDED IN ZZZ1 AND BRIEFED NEW CREW. IT WAS APPARENT DURING THE MAINT COM THAT THE CTLR WAS NOT AWARE OF NORMAL START VALVE LIGHT OPS. THE LIGHT FLICKS BRIEFLY ON-OFF WHILE VALVE CHANGES POS. MAINT THOUGHT LIGHT STAYED ON FOR 15 SECONDS WHILE START VALVE OPEN. A SHORT NORMAL FLICKER LEAVES VERY LITTLE OPPORTUNITY TO CATCH THE LIGHT WHILE WATCHING ALL OTHER PARAMETERS AND INDICATORS DURING THE START PROCESS.