CAPT OF B737-400 DISCOVERS RIGHT ENGINE SPINNING AT HIGH REVOLUTIONS WHILE FUELING AND GND SERVICING CONTINUE UNABATED. DISCOVERS ENGINE START SWITCH HAD STUCK IN THE GND POSITION DURING THE PREVIOUS START.

Narrative

I ARRIVED AT THE GATE FOR DEP TO NAS. TOLD THE PLANE WAS BROKEN AND BEING TAKEN TO THE HANGAR. AFTER A WHILE THE MECHS BROUGHT ANOTHER PLANE FROM THE HANGAR. I WENT DOWN TO THE ACFT. FO SAYS SOMEONE OUTSIDE ACFT IS BANGING ON SIDE STATING R (#2) ENG IS STILL RUNNING. I LOOK DOWN TO SEE PARKING BRAKE SET AND START LEVERS IN CUTOFF POS. I GO DOWN ONTO RAMP TO SEE WHAT IS GOING ON. I SEE FUELER HOOKED UP AND BAGGAGE HANDLERS IN REAR COMPARTMENT; ALL WHILE THE ENG APPEARS TO BE RUNNING AT ABOUT HALF SPD. I TELL THE FUELER TO DISCONNECT AND ALL RAMP PERSONNEL TO GET AWAY FROM ACFT TILL I FIGURE OUT WHAT IS GOING ON. I LEAVE RAMP AND WHILE WALKING BACK TO COCKPIT REALIZE WHAT I AM LOOKING AT IS PROBABLY A STARTER LEFT ENGAGED. MY SUSPICIONS ARE CONFIRMED WHEN I RETURN TO COCKPIT TO SEE START SWITCH IN GND. I REACH UP TAKE START SWITCH FROM GND TO OFF AND ENG WINDS TO A STOP. ACFT WAS APPARENTLY STARTED AT HANGAR ENG WAS RUN ALL THE WAY TO GATE AND THEN SHUT DOWN; ALL WHILE STARTER WAS ENGAGED. I WROTE UP THE EVENT IN THE MAINT LOG. MECHS THEN REPLACED THE STARTER FOR ENGAGEMENT TIME EXCEEDANCE.