A B767-300 EXPERIENCED SMOKE IN THE COCKPIT OVER THE NORTH ATLANTIC. THE SOURCE OF SMOKE WAS TRACED TO THE RECIRCULATING FANS BY USE OF THE CHKLIST AND SATCOM COM WITH MAINT.

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WHILE CRUISING WBOUND AT FL340 AT APPROX 56 DEGS N 20 DEGS W; WE EXPERIENCED AN EPISODE OF SMOKE IN THE COCKPIT. WE HAD JUST COMPLETED A CREW CHANGE BRIEF WHEN I NOTICED AN ELECTRICAL SMELL. AT THE SAME TIME THE CAPT AND RELIEF COPLT NOTICED SMOKE COMING FROM THE JUNCTION OF THE CTR CONSOLE AND THE FORWARD INST PANEL. WE IMMEDIATELY PUT ON OUR OXYGEN MASKS AND THEN WENT ABOUT ESTABLISHING CREW COMS. NEXT WE RAN THE CHKLIST FOR SMOKE/FUMES/ODORS IN THE COCKPIT. UPON COMPLETING THAT CHKLIST; WE BEGAN SEARCHING FOR THE SOURCE OF THE SMOKE. OUR STATUS PAGE ON THE FORWARD INST PANEL TOLD OF THE FORWARD EXHAUST OUTFLOW FAN HAVING FAILED. UPON CALLING THE COMPANY ON THE SATCOM AND BEING TIED IN WITH OUR MAINT CTL CTR; WE WERE INFORMED THAT A FAILURE OF THIS FAN WOULD LEAD TO THE SMOKE AND ODOR THAT WE EXPERIENCED. UPON FAILING; THE FAN'S CIRCUIT BREAKER POPPED AND IN DOING SO ALL PWR TO THE FAN WAS CUT OFF. THIS IN TURN STOPPED THE SMOKE FROM COMING INTO THE COCKPIT. MAINT SUGGESTED THAT WE TURN OFF THE RECIRCULATION FANS TO EVAC THE LINGERING ODOR FROM THE COCKPIT. THEY ALSO SUGGESTED THAT WE CHK BELOW THE FLT DECK IN THE ELECTRONICS BAY TO ENSURE THERE WERE NO OTHER CIRCUIT BREAKERS TRIPPED NOR OTHER SIGNS OF PROBS. WE DISCUSSED THE POSSIBILITY OF A PBE BEING REQUIRED WHILE INVESTIGATING THE ELECTRONICS BAY. SINCE THERE WERE NO LONGER ANY SIGNS OF SMOKE; WE DECIDED IT WOULDN'T BE NECESSARY TO USE A PBE. WE ALSO DISCUSSED THE ISSUE OF DIVERTING. OUR CHKLIST INSTRUCTS US TO LAND AT THE NEAREST SUITABLE ARPT ONLY IF THE SOURCE OF THE SMOKE/FUMES/ODORS CANNOT BE FOUND AND CONFIRMED. WITH THE STATUS MESSAGE; THE TRIPPED CIRCUIT BREAKER; AND THE MAINT CTL CTR'S INPUT; WE FELT 100% CERTAIN THE FAN WAS THE SOURCE OF THE SMOKE AND ODORS. ONCE THE FAN'S PWR WAS CUT; THERE WAS NO LONGER A PROB. ARMED WITH THAT KNOWLEDGE; WE FELT THERE WAS NO REQUIREMENT TO DIVERT. WE CONTINUED TO OUR DEST WITHOUT FURTHER INCIDENT.