Narrative:

Passing through 2000 ft I began my after takeoff checklist. I looked at the fuel flow meters as I began to turn off the boost pumps. I notice the left fuel flow was low. I requested to level at 3000 ft and did so. While checking the fuel valves and mixtures trying to learn about the problem, my altitude jumped around +300, -0 ft. I then turned back to the airport and canceled IFR. The extreme WX changes and cold temperatures caused ice to block my fuel line.

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Original NASA ASRS Text

Title: C310 PLT FLYING CARGO HAS FUEL FLOW METER PROBS DUE TO ICE BLOCKING THE FUEL LINES. RETURN LAND IS THE RESULT.

Narrative: PASSING THROUGH 2000 FT I BEGAN MY AFTER TKOF CHKLIST. I LOOKED AT THE FUEL FLOW METERS AS I BEGAN TO TURN OFF THE BOOST PUMPS. I NOTICE THE L FUEL FLOW WAS LOW. I REQUESTED TO LEVEL AT 3000 FT AND DID SO. WHILE CHKING THE FUEL VALVES AND MIXTURES TRYING TO LEARN ABOUT THE PROB, MY ALT JUMPED AROUND +300, -0 FT. I THEN TURNED BACK TO THE ARPT AND CANCELED IFR. THE EXTREME WX CHANGES AND COLD TEMPS CAUSED ICE TO BLOCK MY FUEL LINE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.