While in cruise, problems were experienced with the left-hand engine. Engine instruments showed a drop in fuel pressure and propeller rpm. Use of the electric booster pump and re-selection of the fuel selector valve enabled the pilot to keep the engine running for a few more minutes before it quit. The engine was shut down and the pilot diverted to a nearby airport. On the descent the pilot was able to re-start the dead engine which ran for a few minutes before quitting again. On final approach the right-hand engine also stopped. A forced landing was made 650 ft short of the runway. Prior to departure, the co-pilot and engineer reported a total of 800 gallons of fuel, sufficient for the entire flight including a stopover. The journey log, however, showed a total of 4900 lb or 680 gallons. On the first leg (4 hours and 45 minutes), 2750 lb of fuel was used (80 gals per hour). After 3 hours and 40 minutes on the second leg, both engines failed due to fuel exhaustion.