A MD80 'L ENG VALVE' LIGHT CAME ON AFTER TKOF. THE FO READ THE QRH FOR THE 'L START VALVE.' THE ENG WAS SHUTDOWN; AN EMER DECLARED AND FLT RETURN TO LAND.

Narrative

I WAS FLYING THE ACFT. SHORTLY AFTER TKOF WE OBSERVED AN 'L ENG VALVE' LIGHT ON THE ANNUNCIATOR PANEL. THERE WAS SOME CONFUSION AS TO IF THIS WAS A START VALVE PROBLEM SO I ATTEMPTED TO TEST THE ANNUNCIATOR LIGHTS SO AS TO SEE WHAT OTHER 'VALVE' LIGHT INDICATIONS WERE AVAILABLE; BUT SINCE THIS WAS AN ACFT IN WHICH I WAS UNABLE TO MAKE SUCH A TEST. I MADE A STATEMENT THAT THE LIGHT DID NOT ACTUALLY SAY 'START VALVE' BUT AFTER SOME DISCUSSION AND INPUT FROM THE FO WE DECIDED TO TAKE THE MOST CONSERVATIVE ACTION AND TREAT IT AS A START VALVE FAILURE. I THEN ASKED THE FO TO PULL OUT THE CHKLIST AS I HAND FLEW THE ACFT; COMMUNICATED WITH ATC AND DECLARED AN EMER. AFTER CLEANUP; I ATTEMPTED TO TURN THE AUTOPLT ON; BUT IT WOULD NOT ENGAGE. AS I FLEW THE FO RAN THE CHKLIST AND STATED THAT WE NEEDED TO SHUT THE ENG DOWN; WHICH WE DID. WE RETURNED TO AN OVERWT LNDG; WHICH WAS UNEVENTFUL. AFTER RETURNING TO THE GATE AND PREPARING TO MAKE A LOG ENTRY; I ASKED THE FO TO SHOW ME WHICH CHKLIST HE RAN. HE SHOWED ME THE 'L START VALVE' LIGHT CHKLIST. I STATED THAT WE DID NOT HAVE THAT LIGHT; BUT RATHER THE L ENG VALVE LIGHT. I WENT TO MY QRH AND FOUND THE 'L ENG VALVE' LIGHT CHKLIST. AT THAT POINT WE REALIZED THAT WE HAD RUN THE WRONG CHKLIST. I CALLED THE CAPT IN THE FLT OFFICE AND ASKED HIM TO COME TO THE ACFT. WHEN HE ARRIVED I EXPLAINED TO HIM WHAT HAD HAPPENED. I ENTERED THE CORRECT DISCREPANCY INTO THE LOG AND NOTIFIED MAINT THAT WE DIDN'T HAVE A START VALVE FAILURE. I ALSO LATER IN THE DAY CALLED MAINT CTL AND NOTIFIED THEM AS TO THE AUTOPLT NOT ENGAGING; WHICH I HAD NOT PUT IN THE BOOK. LATER THAT DAY THE FO AND I WERE REVIEWING THE 'L START VALVE OPEN' CHKLIST AND NOWHERE IN THERE DID IT TELL US TO SHUT DOWN THE ENG. THE FO STATED THAT HE HAD THOUGHT HE READ ON A MESSAGE THAT WE WERE SUPPOSED TO ACCOMPLISH THE FIRST THREE ITEMS ON THE ENG INFLT SHUTDOWN CHKLIST IF WE HAD A START VALVE PROB.