Narrative:

On a trip from pontiac, mi, to waterloo, ont, to buf, the WX was very clod for the time of yr (-15 degrees at surface). As I approached buf VFR, I noticed the left fuel flow gauge fluctuating a lot and eventually the left engine began surging on and off, and I advised approach control that I was having 'engine problems' and would appreciate a straight in approach. I also declined assistance by ground crews when asked. As I got closer to the field and turned downwind, I found it necessary to feather the left engine as it was windmilling. I then advised ATC tower that I 'lost the left engine and am operating on one,' and turned base/final for a normal landing. I overheard the tower say 'emergency traffic rolling out.' (I never declared an emergency at any time.) I preheated the fuel drains and found water (a lot) after draining the sumps. This proved my thought that water was somehow frozen in the system. I also added alcohol at 1% of capacity and departed back to pontiac later in the day. The FAA then called and wanted to know why I flew the same plane back after 'declaring an emergency,' (which I did not). I suggest all pilots use alcohol (it is approved in most airplanes) in the fuel. Even though I did a thorough preflight and drained all sumps prior to moisture froze and wasn't detected until switching tanks in the air at a later time. If the moisture is already frozen during preflight, it obviously can't be removed properly from the fuel system. The alcohol should prevent any frozen moisture in the fuel.

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Original NASA ASRS Text

Title: GA SMT INFLT ENGINE SHUTDOWN. ENGINE SURGING DUE WATER IN FUEL.

Narrative: ON A TRIP FROM PONTIAC, MI, TO WATERLOO, ONT, TO BUF, THE WX WAS VERY CLOD FOR THE TIME OF YR (-15 DEGS AT SURFACE). AS I APCHED BUF VFR, I NOTICED THE LEFT FUEL FLOW GAUGE FLUCTUATING A LOT AND EVENTUALLY THE LEFT ENG BEGAN SURGING ON AND OFF, AND I ADVISED APCH CTL THAT I WAS HAVING 'ENG PROBS' AND WOULD APPRECIATE A STRAIGHT IN APCH. I ALSO DECLINED ASSISTANCE BY GND CREWS WHEN ASKED. AS I GOT CLOSER TO THE FIELD AND TURNED DOWNWIND, I FOUND IT NECESSARY TO FEATHER THE LEFT ENG AS IT WAS WINDMILLING. I THEN ADVISED ATC TWR THAT I 'LOST THE LEFT ENG AND AM OPERATING ON ONE,' AND TURNED BASE/FINAL FOR A NORMAL LNDG. I OVERHEARD THE TWR SAY 'EMER TFC ROLLING OUT.' (I NEVER DECLARED AN EMER AT ANY TIME.) I PREHEATED THE FUEL DRAINS AND FOUND WATER (A LOT) AFTER DRAINING THE SUMPS. THIS PROVED MY THOUGHT THAT WATER WAS SOMEHOW FROZEN IN THE SYS. I ALSO ADDED ALCOHOL AT 1% OF CAPACITY AND DEPARTED BACK TO PONTIAC LATER IN THE DAY. THE FAA THEN CALLED AND WANTED TO KNOW WHY I FLEW THE SAME PLANE BACK AFTER 'DECLARING AN EMER,' (WHICH I DID NOT). I SUGGEST ALL PLTS USE ALCOHOL (IT IS APPROVED IN MOST AIRPLANES) IN THE FUEL. EVEN THOUGH I DID A THOROUGH PREFLT AND DRAINED ALL SUMPS PRIOR TO MOISTURE FROZE AND WASN'T DETECTED UNTIL SWITCHING TANKS IN THE AIR AT A LATER TIME. IF THE MOISTURE IS ALREADY FROZEN DURING PREFLT, IT OBVIOUSLY CAN'T BE REMOVED PROPERLY FROM THE FUEL SYS. THE ALCOHOL SHOULD PREVENT ANY FROZEN MOISTURE IN THE FUEL.

Data retrieved from NASA's ASRS site as of August 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.