As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FUEL BEGAN VENTING FROM RIGHT WING FUEL TANK EN ROUTE YHZ-DTW. FLIGHT DIVERTED TO BOS AND LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED UPPER VENT DRAIN VALVE WITH NO HELP. REPLACED THE LEFT TANK CLIMB VENT FLOAT VALVE. LEAK AND TRANSFER CHECK WERE NORMAL. AIRCRAFT RETURNED TO SERVICE.