What was found
THE FOLD DOWN PELICAN RACK AT THE REAR OF THE ACFT ABOVE THE LOADING TUNNEL WAS INSPECTED FOR THE SOURCE OF SMOKE IN THE COCKPIT. INITIALLY THE CENTRAL PILOTS DISPLAY SYS BOX FANS (2 EA) WERE SUSPECTED OF FAILURE. ONCE THE FAN UNIT WAS REPLACED AND SHIP BATTERY POWER WAS TURNED ON, THE MEDICAL EQUIPMENT AIR PUMP/COMPRESSOR MOUNTED ON THE SAME PELICAN RACK EMITTED SPARKS AND SMOKE. MECHANIC BELIEVES THE PUMP ARMATURE MAY HAVE A DEAD SPOT BECAUSE THE UNIT OPERATED NORMALLY DURING TROUBLESHOOTING OF THE ODOR. A REPLACEMENT AIR PUMP IS ON ORDER.